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The realization that there is a limit to our supply of domestic mineral and fuel resources, which have been taken for granted until recently, has stimulated the need for conservation and optimum utilization of the Nation's minerals, metals, and fuels-resources critical to our national economy. The mission of the Bureau of Mines is to develop new technology, improve existing technology, and disseminate information related to mineral resources and industries. Fulfilling the mission is necessary to insure a continuing, adequate supply of minerals and alternative supplies of energy from reliable sources at the lowest possible cost to society and the environment. Established in 1910, the Bureau of Mines under the Department of the Interior is the Federal Government's primary research arm in the mineral field. Since the transfer of the fossil fuels portion of the energy research program to the newly organized Energy Research and Development Administration (ERDA) in fiscal year 1975, Bureau research has been concentrated on increasing mineral production, decreasing energy usage through more efficient processing, and decreasing material losses caused by corrosion. Concurrently, research is being addressed to improved coal-preparation techniques, especially to expanding utilization of low-grade coals and coals difficult to beneficiate, which are essential for reducing the need for petroleum and natural gas supplies and for redirecting our energy consumption. Fluctuations in the availability of foreign sources of minerals, metals, and fuels due to political and economic variability among nations have necessitated intensified investigation into coal mining, uranium-ore processing, and geothermal energy sources-three alternatives that can help to alleviate the dependence of the United States on foreign sources of energy.

Jan 1, 1975

When the Organic Act of 1910 established the Bureau of Mines within the Department of the Interior, the Bureau's programs involved only health and safety research and education, and fuels testing. As the Federal Government's primary agency for research in minerals, the Bureau has expanded its scientific and technological investigations to mining, processing minerals substances, eliminating occupational health and safety hazards in the mineral industries, economic development, and resource conservation. Today, Bureau activities cover a broad spectrum of programs for meeting the diverse (and sometimes conflicting) needs of mineral industries, government, and the public. In the 1960's, the Bureau initiated programs to resolve environmental problems associated with past mining and mineral processing. In the 1970's, the energy crisis raised the national consciousness concerning our limited supplies of domestic mineral and fuel resources. Dependence on foreign sources of raw materials critical to our national economy and competition from other countries for these world supplies stimulated the need to conserve and use with intelligence the Nation's minerals, metals, and fuels.

Jan 1, 1976

The Bureau of Mines is responsible for a broad spectrum of programs for meeting the diverse and changing mineral resource needs of the Nation. These programs are managed by the Director and two Deputy Directors, who formulate general policy and program direction from the Washington, D.C., headquarters. Bureau program activities are classified into two major functions, minerals research and minerals information and analysis. A senior advisory staff, consisting of the Chief Staff Officer and Chief Scientist, provides advice and consultation to the Director on a wide range of scientific and technical matters and acts on behalf of the Director to maintain liaison with other government agencies, both foreign and domestic, mineral industries, and professional societies. The Minerals Research Directorate Technological research and development in minerals have long been cornerstones of the Bureau of Mines. The Minerals Research Directorate performs this work. Re-search functions cover the extraction, processing, use, reuse, and disposal of mineral materials; the reduction of health and safety hazards in mining and processing; and minimizing undesirable environmental effects. The production, conservation, sale, and distribution of helium is also conducted under the Research Directorate.

Jan 1, 1981

By J. R. Emery, D. F. Coates

"FOUR PAPERS ON CEMENTED BACKFILL were given at the Annual General Meeting of The Canadian Institute of Mining and Metallurgy in 1970:Weaver, W. S., and Luka, R., ""Laboratory Studies of Cement-Stabilized Mine Tailings"".Pasieka, A. R., Beattie, H. F., and Espley, G. H., ""Cemented Hydraulic Backill within the Falconbridge Group of Companies"".McLeod, P. C., and Schwartz, A., ""Consolidated Fill at Noranda Mines Limited (Geco Division)"".Clement, W. P., and Sokoloski, R., ""Pumping Cemented Backfill"".These four papers give the impression of a development in mining technology that has been substantially completed. Somewhat over ten years ago, The Inter-national Nickel Company of Canada, Limited and Falconbridge Nickel Mines Limited started experimenting with the addition of Portland cement to mill tailings to produce improved backfill and cheaper floors for scraping. Shortly after, the Canada Cement Company Limited (now Canada Cement Lafarge Ltd.), with full support of the two mining companies, started an extensive research program to provide the technologic-al data necessary to exploit what was obviously going to be a significant development in mining technology."

Jan 1, 1970

By Arthur L. Hall

The purpose of this symposium is to challenge industry to better air classification, and as a first step toward fulfillment, to spotlight three fairly recent, aerodynamically designed, highly efficient air classifiers. This discussion does not intend to imply that present practice is bad. Actually, when present air separators are used for the jobs for which they were originally designed, they give high production and uniform operation, with a minimum of maintenance. The customers of nonmetallic mineral pigment producers, however, are making increasing demands for finer products, such as 99.9 pct -20µ, which appears to be beyond the economic capabilities of standard air separators industrially used over the last 10 to 30 years. Here is an actual example. A 10-ft diam pebble mill is in closed circuit with a conventional 12-ft diam centrifugal air separator, grinding 20-mesh wollastonite to a series of fine grades up to 99.97 pct - U.S. No. 325 mesh (44µ). Fig. 1 shows variations in fineness of mill discharge (or air separator feed), recycle for regrinding (or air separator tails), and product as measured by a wet rotating sieve test. For example, when the mill is turning out a product 80 pct -325, the mill discharge or separator feed is 30 pct -325, and the coarse tailings or recycle is only 5 pct -325. Hence 25 pct of the 30 pct available is accepted as product. This is efficient separation, and the ratio of recycle to feed is only about 2: 1. How- ever, to make a product testing 99.97 pct -325 the separator feed is 62 pct -325 and the coarse tailing 60 pct -325. In this case the recycle ratio is about 13: 1 and the economic limit to produce fineness has been substantially reached with this given equipment and process arrangement.

Jan 10, 1957

By T. G. Carter

"This paper traces the introduction and use of fire-resistant (FR) fluids in hydraulic systems at underground mines in British Columbia. Reasons are given for the decision to make compulsory the use of such fluids in underground mines after January 1, 1975 by provincial government legislation. Examples are quoted of fires caused, or supported by, mineral oils which have resulted in loss of life and property.The basic principles of hydraulic systems are reviewed in order to present the effects of changing a system operating on mineral oils to one which must operate on FR fluids. Approximations of the cost of system conversions are given for certain machines and a brief survey is made of the various pieces of underground equipment which contain hydraulic systems operating on FR fluids.IntroductionIn 1948, Admiral Ben Moreel , who was then president of Jones and Laughlin Steel Corporation in the United States , wrote:""Although safe and healthful working conditions can be justified on a cold dollars-and- cents basis, I prefer to justify them on the basic principle that it is the right thing to do. ""(1)This paper will outline the introduction and use of fire resistant fluids at mine operations in the Province of British Columbia. That it was the right thing to do in enhancing the safety and well-being of every person employed at the mines was the prime consideration. That it may be justified on a cold dollars-and-cents basis is left for the reader to judge. The prime purpose of this paper is not so much to trace the efforts made by the individual mines to successfully introduce and use fire-resistant (FR) fluids in hydraulic systems, but to present an over-all picture of what occurred, in a collective sense, at the majority of mines which have ended up with a working FR fluid system. The problems attendant to the introduction of an FR fluid will be recounted in a manner which, it is hoped, will prove useful to those contemplating system conversions. Because the predominant fluid now in use is an invert, or water-in-oil. emulsion, this will be the FR fluid considered.Fluid Loss from SystemsThe quantities of various fluids required for use in hydraulic systems are extremely high. This statement in itself may appear to be redundant in that the capacities of the various systems should demand that a fixed amount of fluid is required for the initial filling of a system, with a further amount of fluid scheduled for use during subsequent fluid changes, i.e. at the recommended change intervals . If only this were the case!"

Jan 1, 1981

By Kunio Hashimoto

The conventional troughed belt conveyor system is the most widely used form of equipment for transporting bulk materials in the world today. The reason is not only because it is possible to transport a great deal over a long distance when compare to other types of equipment but also due to its greater economic efficiency and low initial and running costs. When dry, powdery materials and liquid materials are being conveyed, there are enclosed transport methods such as flow, case, air-slider and pipe line. In addition to features of the belt conveyor, a system employing a pipe line to transport dry powdery and liquid materials has always been considered an ideal method. This has been brought into reality through the Pipe Conveyor Sys tem.

Jan 1, 1984

By Patrick Laflamme, Jean-François Boulanger

Les minerais de cuivre sulfurés, qui représentent 80% de la production mondiale de cuivre, imposent une étape de concentration des minéraux, premièrement pour atteindre une teneur en cuivre minimale qui permette le traitement pyrométallurgique, mais aussi pour limiter la présence d’élément pénalisants (délétères). Cette introduction offre un survol des principes, limites et pistes d’améliorations touchant la concentration des minéraux de cuivre.

May 2, 2024

By Alexandra Garcia

A measurement-based ground control management system, commonly employed in coal mines, has been successfully implemented in a UK potash mine operating at a depth of over 800 m. This system includes the routine deployment of telltales in roadways throughout the mine to mitigate against the risk of large-scale roof falls and the deployment of detailed ?design monitoring? instrumentation for ongoing design verification. The routine monitoring systems used in coal mines have not been, to date, commonly applied in potash mines, despite the similar, variable weak geology and associated ground control hazards. Monitoring information from the site indicates that telltales can be deployed to monitor roof conditions, with action levels based on differential rates of strain, as opposed to absolute movement.

Jan 1, 2014

By I Sheppard, A Hills

This paper describes a multi-lift bench stoping method introduced recently to extract the narrow silver-lead-zinc orebodies at the Isa Lead Mine. Cut-and-fill methods were chief mining methods for the narrow orebodies at the mine over 35 years ago. Benching methods were introduced approximately two decades later, and quickly replacing the cut-and-fill methods. The benching methods had improved both the economy scale and safety of the mining operation. The multi-lift benching method combines a number of bench lifts into a single stope to further improve the operational efficiency. Three stopes in the initial multi-lift benching trials are described.

Jan 1, 2003

By Justin Jensen, Luis Moya, Jose Carlos Durazo, William Szolga, Tyler McCallum, Tim Doubleday

Sulfuric acid mist is an undesired by-product of the copper electrowinning process, caused by oxygen evolution at the anode which entrains droplets of the acidic copper electrolyte solution. As the oxygen moves to the surface of the cell, these droplets become aerosolized resulting in acid mist. The addition of chemical anti-misting agents to the copper electrolyte is a common mitigation technique. This paper details Syensqo’s laboratory development of a new environmentally friendly acid mist suppressant, ACORGA® EW98. The product exhibits excellent acid mist suppression and it is fully compatible with the adjacent solvent extraction process. Lab and pilot test results are reviewed ahead of future planned industrial trial testing.

Feb 1, 2025

By Renn Oler

Corrosion can often cause significant strength reduction and failure of steel rockbolts, thus demanding continuous rehabilitation and posing challenges to underground mines in maintaining long term ground support. The mining industry has traditionally applied galvanized and epoxy coatings for protection of ground support and reinforcement in corrosive environments due to cost considerations. However, under a harsh and corrosive groundwater condition with extreme pH levels, failure of the existing coated rockbolts often results in failure and falls of the mine roof, especially in long-term mine drifts or entries. To prevent the roof falls induced by corrosive bolt failure, DSI developed a new polymer coating, called ?Obduro AP coating,? to combat harsh and corrosive ground conditions. The new polymer coating was tested in extreme conditions to identify weaknesses and was found to be capable of handling highly corrosive mine water solutions. This paper highlights the challenges faced by underground mines with corrosive bolt failure and shows that the DSI Omega BoltTM can withstand the most corrosive ground conditions when it is coated in the new, economic Obduro AP coating.

Jan 1, 2014

By Sakellariou M., Ferentinou M.

Determination of the nonlinear behavior of multivariate dynamic systems often presents a challenging and demanding task. Therefore, complex geomechanics systems are an ideal area for the application of intelligent methods. Often the physical problem is controlled by nonlinear equations, conveying to the use of neural networks. Hudson, (1992a), aiming at efficient engineering modelling and design, introduced and developed Rock Engineering Systems (RES) approach, through the implementation of generic interaction matrix GIM. This approach has been used for a wide variety of rock engineering and other problems, resulting in many case studies available, which illustrate the application of RES to rock engineering problems. Considering the spectrum of the coding methods for the Generic Interaction Matrix, we suggest an objective coding approach. Among the five proposed coding GIM methods, the coding method according to the slope of Pi and Pj relation is relatively accurate, but it might be difficult or impossible to establish or estimate the exact relation of Pi vs Pj for most of the variables involved within a rock engineering system. Self organising maps, are a special type of unsupervised artificial neural networks, which can learn from complex, multidimensional data, and transform them to visually decipherable clusters. The proposed, coding of the GIM, is performed through the combined use of scatter plots produced through, (SOM), and the coding according Pi vs Pj slope. Naghadehi et al., (2013) constructed a database of worldwide experience, in open-pit mine slope stability, the selection of the principal factors was based on Hudson (1992a) who proposed an ‘atlas’ of factors affecting the stability of rock slopes. Slope classification was performed according to status of stability. The rating of the GIM matrix was completed, coupling scatter matrix produced by SOM training, and Pi vs Pj slope plot. Results refer to the identification of clusters, according to status of stability within the original multivariate data set, and the rating of the principal factors according to the dominance and interaction intensity within the open pit mines RES.

Jan 1, 2015

By E M. Jones

On 26 June 2000 a hydraulic fill retaining barricade failed at the Bronzewing mine in Western Australia. The barricade failure resulted in the release of 19 000 m3 of saturated hydraulic fill into the mine, which caused the deaths of three miners. Following this tragic accident, the practices and procedures of mines using hydraulic fills came under intense scrutiny by regulatory bodies and mining companies. At this time, the use of hydraulic fill at NormandyÆs zinc/copper Scuddles mine was suspended and waste rock became the sole backfill material in use underground. By 2003, development of the mine adjacent to Scuddles, Gossan Hill had progressed to a point where a self-supporting fill material was required to enable full recovery of high-grade ore. Cemented hydraulic fill (CHF) was identified as the optimal fill type and work began on designing appropriate management procedures and controls to ensure the safe implementation. This work included definition of the fill properties, plant design and construction, reticulation system design, design of stope barricades and drainage systems and fill placement control and monitoring practices. CHF placement began on 16 July 2004 and has continued to date. Significant operational experience has since been gained in areas including plant performance, fill product quality assurance, barricade construction, stope drainage and in situ performance.

Jan 1, 2008

On the 26th of June 2000 a hydraulic fill retaining barricade failed at the Bronzewing mine in Western Australia. The barricade failure resulted in the release of 19,000 m3 of saturated hydraulic fill into the mine and caused the deaths of three miners. Following this tragic accident, the practices and procedures of mines using hydraulic fills came under intense scrutiny by regulatory bodies and mining companies. At this time, the use of hydraulic fill at Normandy?s zinc/copper Scuddles mine was suspended and waste rock became the sole backfill material in use underground. By 2003, development of the adjacent Gossan Hill mine had progressed to a point where a self supporting fill material was required to enable full recovery of high grade ore. Cemented hydraulic fill (CHF) was identified as the optimal fill type and work began on designing appropriate management procedures and controls to ensure the safe implementation. This work included definition of the fill properties, plant design and construction, reticulation system design, design of stope barricades and drainage systems and fill placement control and monitoring practices. CHF placement began on 16th July 2004 and has continued to date. Significant operational experience has since been gained in areas including plant performance, fill product quality assurance, barricade construction, stope drainage and in-situ performance.

May 1, 2007

WMC Resources Ltd has been involved the development and trialling of an automated load haul dump vehicle system since 1997. This paper describes the introduction of the system into the Olympic Dam Operation and its performance compared with existing manual loaders. In certain situations the autotram loader will outperform the manual operation, particularly on the longer distances. There were no personnel injuries associated with the operation of the system during the testing period.

Jan 1, 2005

Powercoal Pty Ltd operates eight underground coal mines in New South Wales and produces coal for both domestic power stations and the export market. Approximately 40% of total production is from continuous miners. Over the past five years, place change mining methods have been introduced to improve productivity from continuous miners. This has involved utilising the existing coal clearance system from the continuous miner to the ratio feeder using trailing cable shuttle cars.By late 1996 average productivity at Cooranbong Colliery using this system had plateaued at 800 tonnes per eight hour shift. A number of factors were identified to increase average productivity to 1500 tonnes per eight hour shift. An improved coal clearance system was one of the factors identified.

Jan 1, 1998

By Huilan Yang, Feng He

This paper intends to introduce the development of copper smelting and converting technologies in China in recent years, with a particular emphasis on the introduction of various continuous converting technologies, and moreover, it analyzes the advantages and disadvantages of those technologies, including their impact on the downstream anode refining from different points of view. INTRODUCTION At present, many converting technologies are used in copper pyro-metallurgical plants in China, including Peirce-Smith (PS) converter, flash converting furnace, multi-lance based top blowing, bottom blowing and so on. These technologies have spanned a wide range of time. PS converter technology has been applied in copper smelters for many years and most of the blister copper have been produced by this technology; flash converting technology has been developed since 1990s and been maturely applied in several plants up until now; top blowing and bottom blowing technologies have been revived in China in the past decade and boast good environmental protection performance, energy efficiency, throughput capacity and short process flow. All of the said technologies have reference operations in treating high-grade matte. As more and more attention is paid to environmental protection globally and copper smelters continuously seek for cost reduction, it is necessary to share those converting technologies, especially those new converting technologies derived in China, with copper smelting practitioners in the world. This paper aims to analyze the advantages and disadvantages of various technologies from a macroscopic view and discuss their actual application effects, current developments and future improvements. BRIEF INTRODUCTION OF VARIOUS CONVERTING TECHNOLOGIES IN CHINA China has seen a rapid development in copper smelting industry in the past 30 years and has become the largest gathering place of copper smelters in the world, most of which are operating with PS converting furnace technology, however, with the increasingly strict environmental requirements of the Chinese government in recent years, the low-level pollution issue and the disadvantage of large gas exhaust amount per unit of copper of converting furnaces are particularly prominent.

Jan 1, 2019

By G Mulder, M Adams

Since the introduction of raiseboring 30 years ago there have been many operational and mechanical design improvements in the raiseboring machine, its reamers and associated cutters. These have now made the technology of raiseboring a routine and practical operation within the underground mining world. Over the last decade these advances have been aided by the introduction of robust automation packages which have allowed unattended drilling and reaming, real time performance monitoring and enhancement and the rapid diagnostic investigation of mechanical and electrical abnormalities. The constraint to higher raiseboring performance is now the drill string. However when it comes to a cost-effective solution of applying the high drill string torque and tension necessary for the next step change in performance, designers have æhit the wallÆ. Whilst carbon fiber reinforced plastic composites with abrasive resistant sheaths may offer a solution, the limit of conventional steel, drill string technology has been reached. This limit to advancement is however based on the drill string being in tension and alternative solutions may exist by literally turning the raiseboring paradigm on its head. This paper describes the story of a small Australian company engaged in the design and manufacture of mechanical excavation machines, two Australian raiseboring contractors and three Australian mines going against tradition and pushing down rather than pulling up.

Jan 1, 1998

By T. P. Letsebe, L. Magwaza, T. A. Sethu, S. M. Rupprecht

"The authors were tasked with introducing safe and efficient drilling and blasting practices to a small artisanal mine located in the Eastern Province of Rwanda. The current mining methods employed at the mine are inefficient as rockbreaking is conducted utilizing hammer and chisel, or by drilling and blasting with no understanding of the rockbreaking process. The paper discusses the drill and blast cycle, as well as the associated activities necessary to support the mining cycle. The challenges and critical aspects in implementing drill and blast activities are discussed, as well as some of the technical aspects, i.e.drilling pattern, initiation and timing of the blast, and handling of misfires. Ancillary issues such as ventilation, training, communication, effective planning, logistics, and human relations are also examined. IntroductionRockbreaking accounts for 60% of the direct mining costs in small-scale mining. When drilling and blasting practices are poorly implemented the process becomes inefficient and dangerous. The introduction of a proven drill and blast system to artisanal mining offers a number of challenges, with safety being considered the backbone of any sustainable operation and a standard that cannot be compromised.The paper is based on a project at an artisanal cassiterite (tin) mining operation in a small village in the Kayonza District in the Eastern Province of Rwanda. A drill and blast programme utilizing industry best practice was introduced at an underground development end; a raise developed at an inclination of 23 degrees. The underground working is accessed via a 17 degree incline shaft with an operating length of 105 m and serviced by a single drum winder. The winder operates at a speed of about 3.5 m/min hoisting two 1 t wagons from the bottom of the incline to surface for tipping (Figure 1)."

Jan 1, 2017