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By B. A. Comley

Over the past few decades a great deal of effort has gone into characterizing the effects of frother type and concentration in flotation using a variety of two-phase techniques. Whilst useful and informative, this research still does not assist in the selection of suitable frothers for three-phase industrial-scale froths. This paper investigates the effects of frother type and concentration in a three-phase industrial froth. The objective was to determine if progress could be made in terms of understanding the behavior of frothers in flotation and understanding how they affect the sub-processes occurring in the pulp and froth phases and, ultimately, the metallurgical performance of a flotation cell.

Jan 1, 2007

By Robert F. Kaufmann

INTRODUCTION In response to the Uranium Mill Tailings Radiation Control Act (Public Law 95-604, Section 114c), a report has been prepared by the U.S. Environmental Protection Agency (1980) which describes the potential health and environmental effects associated with uranium mine wastes. The author was responsible for the geology, hydrology and aqueous pathways analysis portions of the report. All potential sources of contaminants, solids, liquids, and airborne emissions, which might cause adverse impacts upon the environment or health of nearby populations were considered. Wastes at both active and inactive uranium mines (Hans and O'Connell, 1981) are described and assessed with respect to dose and health effects (Blanchard et al. 1981). The emphasis of this paper is on the liquid emissions and the aqueous pathway. Model uranium mines were developed for surface and underground mines. The model underground mine was placed in New Mexico while the model surface mine was in Wyoming. Development of a generic assessment was complicated due to the inherent variability of uranium mines. Also, most information available relates to uranium mills rather than to mines, or reported measurements were often influenced (biased) by wastes from a nearby mill and did not specifically reflect mine discharges. Consequently, the assessment presented is often based on conservatve (maximizing) assumptions which are identified as such, and which were based on knowledge from field investigations, available literature, and consultations inside and outside the U.S. Environmental Protection Agency. Maximum use was made of available data, supplemented with limited field studies in Colorado, Texas, New Mexico, and Wyoming. PREVIOUS INVESTIGATIONS Stream survey work in Colorado by the Water Pollution Control Commission and the U.S. Geological Survey (Moran, 1974; Wentz, 1974) mentioned a portion of the Uravan Mineral Belt and uranium mines therein, but the work did not emphasize uranium mines. Significant amounts of acidity and total trace metal concentrations were found in streams from 18 different mining areas. Dilution and chemical precipitation below mine drainages decreased concentration and increased the pH. Given enough time and distance, the streams recover naturally, but the accumulations of trace metals in the sediments increase. Field observations in 1971-72 of streams in most of Colorado indicated that approximately 724 km of streams in 25 different mining areas were adversely affected by mine drainage (Wentz, 1974). Discussions of the impacts of uranium mining on water quality or quantity are incidental in numerous impact statements and environmental reports prepared by industry and (or) the U.S. Nuclear Regulatory Commission as an integral part of licensing or relicensing uranium mills. Coverage on mining is usually minor as the principal focus is on milling impacts. The same is true for the recently prepared generic EIS on regulation of uranium milling (U.S. Nuclear Regulatory Commission, 1979). Radiochemical assessment of surface and groundwater in uranium mining districts of New Mexico is done by self-monitoring programs associated with NPDES permits. Also, radiochemical assessment studies have been funded by the New Mexico Environmental Improvement Division and U.S. Environmental Protection Agency. Unfortunately, there has been no concerted effort to prepare broad assessments of the cumulative impacts of mining and milling in areas of interest in Texas, New Mexico, and Wyoming. Critical review and synthesis of these types of data can produce rather useful information. For example, the publication "Water Quality Impacts of Uranium Mining and Milling Activities in the Grants Mineral Belt, New Mexico" (U.S. Environmental Protection Agency, 1975) addresses the groundwater and surface water changes as the result of extensive uranium mining and milling production in a relatively confined area. A more recent report by the Wyoming Department of Environmental Quality summarizes 16 years of aqueous radium and uranium data. The study reports significant amounts of radium-226 and uranium were present in surface water in the Shirley Basin as a result of inadequate mine water treatment (Harp, 1978). In Texas, surface water and groundwater monitoring conducted by industry, as well as by State and Federal agencies, reveals little or no change of chemical quality attributable to uranium mining and milling (Gesell, 1977; Kallus, 1976). This conclusion is based on 586 samples collected from 198 stations over a period of 39 years, but primarily from 1961 to 1975. The State monitoring program by several agencies is continuing, but data reporting and interpretation is lagging. One survey (Itin, 1975) showed that none of the mine water from the 10 lakes that were sampled was suitable for human use. The lakes were also unsuitable for irrigation due to mineralization of the water by sulfate, chloride, and TDS. One of the 10 was suitable for stock watering.

Jan 1, 1981

By James N. Gundersen

Geological Engineering can be all-encompassing and it necessarily overlaps many applications of economic and applied geology. Other review articles will cover specific developments in rock mechanics, open-pit and underground mining, geology, geochemistry, geophysics and geohydrology- all of which overlap many fields of economic and applied geology. Nevertheless, there still remains a diversity of new and innovative applications of geology to engineering works through the activities of federal and state agencies, college and university departments, and industrial or consultant firms-particularly with respect to the properties of earth materials and their behavior "as-is" in nature or under the stress of engineering works. Governmental Agencies: Federal John T. McGill (Chief: Engineering Geology Branch; USGS, Denver) relates that recently the Engineering Geology Branch, together with several other branches of the Office of Environmental Geology, has undertaken the production of interpretive maps of unusual character. These maps are commonly called special-purpose or single concept maps. A folio, or series of maps, is prepared for each topographic quadrangle or area selected for study. The individual maps in a given series are printed on standard-size sheets so that they can be bound together if desired.

Jan 3, 1974

By Dean Millar

Clean, green, cheap compressed air can be produced efficiently and renewably by modernization of a 19th century technology ?The hydraulic air compressor has no moving parts ?After commissioning, the Ragged Chutes HAC operated for 70 years, only being stopped twice for repairs to the intake heads ?Operates using hydropower from Montreal river ?Produced air for ~29 silver mines in Cobalt, 20 km distant

May 1, 2013

By O. P. Garg

"The Iron Ore Company of Canada (IOC) operations in Labrador and Quebec, in Canada, is among the largest openpit mining complexes on a world wide basis. Since the 1981-82 recession, IOC has embarked on a comprehensive cost reduction and productivity improvement program in order to survive in the world iron ore market.This paper will outline the approach used in prioritizing the cost reduction items.IntroductionMuch of the mining industry in North America is in a crisis state. Most producers are operating at production levels well below capacity, some have been merged or sold, while others have been mothballed or closed permanently. For many of us still operating, the future is uncertain. Despite the many cutbacks and closures, there is still an abundant supply of minerals in the world market and there is almost no hope for any relief on price pressures on most mineral commodities in the near future. The Iron Ore Company of Canada (IOC) operates an iron ore mine, a concentrator and a pellet plant known as the Carol Project located in Labrador City, Newfoundland. This concentrator and the pellet plant have the annual capacity to produce 20 million and 10 million tons respectively. A company owned and operated railway links this operation with the dock terminal facilities in Sept-Iles, Quebec.In the past decade the Iron Ore Company of Canada has been one of the largest producers of iron ore products in the world. Its pellets and concentrates as well as natural ores were sold in North America, Europe and the Far East. In 1981-82, sales, particularly in North America, went into a serious decline. For almost 30 years, the gospel IOC preached to employees was ""production, production!"" There were many innovations, and millions of dollars were spent on the biggest and best equipment, on research and development, on training and developing employees."

Jan 1, 1987

The Beginnings of Mineral Processing Research in Canada - A Short Account

Sep 13, 2010

This paper presents the results of a unique study conducted by the National Institute for Occupational Safety and Health (NIOSH) from 2016 to 2019 to evaluate the effects of longwall-induced subsurface deformations on shale gas well casing integrity and underground miner safety and health. At both deep and shallow cover instrumentation sites, surface subsidence measurements, subsurface in-place inclinometer measurements, and underground pillar pressure measurements were conducted as longwall panels were mined. Comparisons of the deep and shallow cover test site results with those from a similar study under medium cover reveal an interesting longwall-induced response scenario. Under shallow and medium covers, measured horizontal displacements within the abutment pillar are one order of magnitude higher than those measured under deep cover. Conversely, measured vertical compressions under deep cover are one order of magnitude higher than those under shallow and medium covers. However, FLAC3D simulations of the casings indicate that, in all three cases, the P-110 production casings remain intact under longwall-induced deformations and compressions, which has serious implications for future mine design in areas where shale gas wells have been drilled ahead of mining.

Jan 7, 2020

By Edmund S. Leaver, A. P. Towne, Jesse A. Woolf

Part of the work of the Precious Metals Section is to conduct oretesting experiments on ores selected as representative of various mining districts or areas . The projects are authorized by the Metallurgical Division , and only those ores in which gold and silver or gold or silver constitute an essential part of the total values are assigned to the Precious Metals Section . Such ores include those containing the precious metals only as commercially important ingredients , as well as those containing base metals such as copper , lead , and zinc along with the gold and silver . In many instances the "ore " may be a tailing product of a grade good enough to warrant retreatment , or a concentrate for which it is desirable to develop a method of treatment to avoid the expense of shipment to a smelter . It is evident that in general the greater part of this ore - testing work is done according to standard testing procedure , such as cyanidation, amalgamation, gravity - concentration , and flotation , or a combination of these methods . The standard methods of conducting such tests have been outlined in previous reports of ore - testing studies . However , since the inauguration of this oretesting program 6 years ago , the ores submitted under authorization have become increasingly more refractory to simple methods of treatment. Consequently, a considerable number of the projects completed during the fiscal year 1941 have required an unusual amount of work and in some instances have developed into real research problems . For such ores more complete microscopic and spectroscopic examinations and more complete chemical analyses

Feb 1, 1942

By John Nagy

To facilitate increase in the rate of coal production the Bureau of Mines conducted a study several years ago, on the basis of which the allowable charge limit for permissible explosives in single-hole blasting was raised from 1.5 to 3.0 pounds. Further demands for accelerated production led to consideration of multiple blasting in coal, a practice that is deemed hazardous and is not permitted by most States in this country. In multiple blasting, 10 to 20 pounds of explosive or more may be detonated in a coal face within a fraction of a second, which might result in blown-out or blown-through shots with possible ignition of gas or coal dust. As experimental evidence was lacking, in January 1949 an investigation was undertaken in the Experimental coal mine at Bruceton, Pa., principally to study and compare with single blasting the condi-tions under which simultaneous multiple blasting and particularly multiple short-delay blasting may be practiced without danger of igniting gas or coal dust in mines. The first report on this subject was presented at the last international conference of mine safety research. Since that time numerous additional experiments have been made; because of other pressing problems the work has been brought temporarily at least to a conclusion. This paper is the second report on the problem. It does not contain a detailed description of all test conditions and test arrangements, many of which were described 2 years ago in part 1 (now available as Report of Investigations 4868), but the conclusions are based on the entire study. A more complete review, which will incorporate data from the entire investigation, is being prepared as a Bureau of Mines bulletin. Up to the present time, short-delay blasting of coal in commercial mines has been introduced only experimentally in Washington and in a few mines elsewhere. If the system is adopted more generally, new problems may arise, and the study may have to be reopened.

Jan 1, 1952

By A. Yaghini, Y. Pourrahimian

"Human factors (HFs) play an important role in the mining and mineral industry, affecting operational and maintenance efficiency and safety. Despite the introduction of new technologies and automation in this sector, it is well known that a significantly large proportion of total human errors occur during the operation and maintenance phase. A comprehensive literature review of HFs across several industries is provided. From this review, the impact of HFs on operation and maintenance is summarized, with a focus on what the mining industry is currently doing and what opportunities exist for additional improvements. Future research directions and themes are also identified.RÉSUMÉ Les facteurs humains (FH) jouent un rôle important dans l’industrie des mines et des minéraux, en ce qu’ils affectent l’efficacité et la sécurité de l’exploitation et de l’entretien. Malgré l’apparition de nouvelles technologies et de l’automatisation dans ce secteur, il est bien connu qu’une grande partie des erreurs humaines (EH) se produisent durant une phase d’exploitation et d’entretien. Cet article propose une analyse documentaire approfondie des FH dans plusieurs secteurs. L’impact des FH sur l’exploitation et l’entretien est résumé à partir de cette analyse, une attention particulière étant accordée à l’évolution de l’industrie minière et aux possibilités d’améliorer davantage ses activités. Sont également identifiés les futurs thèmes et voies de recherche.INTRODUCTIONDuring the past several decades, the mining industry has focused on improving equipment, machinery, and methods that have led to more advanced hardware and software, equipment with higher reliability and productivity, and other technological advancements. These actions have improved safety and productivity and have reduced casualties and maintenance workload. Although today’s mining equipment and machinery are technologically advanced and highly reliable, the risk of accidents is still relatively high and key performance indicators have not improved significantly compared to other industries (Sorensen, 2012). A prominent reason could be due to insignificant integration of human factors (HFs) as part of planning, operation, and maintenance activities. The current mining system is a people system, and inevitably HFs and human error (HE) figure prominently in all aspects of this industry. Even the most advanced technologies and innovations require operators and maintainers with significant knowledge and skill, which could increase the potential for HE."

Jan 1, 2018

By Louis J. Cabri

"Mineralogical evaluation of ores containing platinum-group elements (PGE) is fraught with difficulties because of the low grades (often 1-3 g/t PGE), dispersal of PGE (usually as finegrained platinum-group minerals [PGM]), as well as occurring in solid solution in some base metal sulphides (BMS) such as pentlandite and pyrrhotite. Mineral processors not only need to know how the PGE are distributed, that is, their mineralogical distribution, but the grain sizes of the PGM, and especially the associated minerals.After obtaining a representative ground sample, common approaches include studying a large number of polished or polished thin sections, concentration of the PGM and sulphides by different gravity methods (e.g., heavy liquids, elutriation, micro-panning) and study of the produced concentrates. Unfortunately, these methods often do not produce concentrations that are sufficiently representative of a particular ore. The newly developed patented technology of hydroseparation (Rudashevsky et al., 2002) is especially effective at making concentrations of PGM over a wide range of concentrations (down to <300 ppb Pt+Pd+Au) and size fractions, including <45µm (down to a few micrometres in size), a size range not possible by other techniques. This water-based environmentally friendly laboratory technique provides a large amount of data from samples, which can range from 5 to 1000g, giving confidence to extrapolation of results to bench-scale and larger test work, especially when combined with quantitative image analysis to determine modal percent of major minerals and mineral liberation data, needed to predict the minimum (K80) and optimum (K40) grinds. INTRODUCTIONThe invention of the electron microprobe in the early 1960’s and scanning electron microscopes (SEM) with energy dispersive spectrometers (EDS) in the 1970’s presented mineralogists with powerful tools permitting them to obtain chemical and surface area data on minute amounts of minerals in situ, in a non-destructive manner. An area of process mineralogy that has very much benefited from this new technology was the characterization and understanding of PGM species, resulting in rapid growth of newly characterized species (Figure 1). Recognition of the first PGM may be ascribed to the Spanish explorer Ulloa in 1748, who described native platinum from South America. The second PGM (laurite, RuS2) was only recognised in 1866 by Wöhler in placer samples from Borneo (now Kalimantan) and the third (sperrylite, PtAs2) by Wells in 1889 from the Sudbury Ni-Cu sulphide deposits. The discovery of the important Pt-Pd deposits in the Bushveld Igneous Complex led to the characterization of the important Pt-Pd sulphides (cooperite, PtS2 in 1928 and braggite, (Pt,Pd)S2 in 1932). By the early 1960’s, only about 20 PGM were recognised, and many later proved to be poorly or incompletely characterized. Thus, the introduction of electron probe microanalysis (EPMA) led to a 50% increase of known PGM, as shown in a 1972 review on PGM (Cabri, 1972). At the time of the next review in 1981 (Cabri, 1981) the number of known PGM had grown to 75 and as of 2002, it had increased to 109 (Cabri, 2002). However, it is the author’s experience that less than about 25 PGM may be considered to be “common”, i.e., found in many different deposit types, as shown in Table 1, but usually only some of these occur in any one particular deposit."

Jan 1, 2004

By Michel Doyon

Canadian Context: Exploration ??Space Exploration is within the unique mandate of the Canadian Space Agency ??Global partnerships ??Maintain close relationship with our partners ??New knowledge in S&T ??Retain and attract highly qualified personnel ??Participation in missions leads to design roles in industry and academia ??Collaboration between government laboratories, industry and academia

May 1, 2009

By Sabina Strmić, Fredrik Sahlström, Siv Hjorth et al

Cobalt is critical for the green energy transition, yet the mineralogical distribution and the mechanisms of concentration of Co in different types of hydrothermal ore deposits remain poorly constrained. Here we document ore mineral assemblages from the active Fåvne and Loki’s Castle seafloor massive sulfide deposits located along the Mohns Ridge in the Norwegian Sea, and determine their whole-rock and mineral chemical compositions with a special emphasis on Co.

May 10, 2023

By J. L. Holman

The Bureau of Mines has extended its previous development of cast Mn-Cu damping alloys to powder metallurgy (P/M) consolidation of alloys containing 55 to 75 wt-pct Mn. Blends of minus 200-mesh elemental powders were compacted cold in directional and isostatic presses. With 1 pct binder, typical green densities ranged between 76 and 80 pct of theoretical when pressing at 30 or 48 tsi. Green strength increased with compacting pressure and copper content. As-sintered tensile strengths ranged to 60,000 psi fox a hydrogen, sintered 60Mn-40Cu alloy, along with 5-pct elongation. Sintered densities ranged between 90 and 96 pct of theoretical. Sintering (a as effective when holding for 1 hr at maximum temperatures of 900° to 1,040` C, dependent on composition. Strength and ductility were considerably lower than for equiva¬lent cast alloys. When aged to the damping condition, alloys containing 60 to 70 pct Mn exhibited >40 pct specific damping capacity (SDC) at 5,000-psi stress, considerably higher than values reported for equivalent cast material. Effects of 1 or 3 pct Sn or Zn additions on SDC and other properties were assessed. Trials were conducted on consolidating rings and gears of the 65Mn-35Cu alloy on industrial-type P/M equipment.

Jan 1, 1979

By R. E. Head

[Surveys of the manganese situation conducted by the Geological Survey and other agencies have distinctly established the fact that the tonnage of high- grade manganese ore in the United States is relatively small. It is therefore obvious that large-scale production of manganese is possible only through beneficiation of low-grade material. ]

Jan 1, 1941

By Zhuofei Yang, Jidong Kang, David S. Wilkinson

The fatigue behavior of AM60 high pressure die casting magnesium alloys was studied in a straincontrolled manner. The fatigue test was interrupted every 2,000 cycles for X-ray tomography scanning. The specimen was removed to be scanned on a desktop micro-CT system. The value of using X-ray tomography in a fatigue properties study was assessed with respect to porosity, cracks and fracture surfaces. The 3D analysis and model results showed porosity could be well measured and modelled in 3D. Defects bands are made of pores under 50 µm in volume-equivalent sphere diameter. Larger pores are randomly distributed in the region between two defect bands. Observation of cracks by X-ray tomography occurs in three ways such that the 3D model gives the best illustration of crack-porosity interaction while the other two methods have better detectability on crack initiation and crack tip observation. X-ray tomography is also of value in failure analysis on fracture surfaces. By summarizing X-ray tomography data during fatigue testing and observing fracture surfaces on a 3D model, a better understanding on the crack initiation, crack-porosity interaction and the morphology of fracture surface is achieved.

Jan 1, 2014

By C. Laughton

Construction of a Deep Underground Science and Engineering Laboratory(DUSEL) is proposed under the auspices of the US National Science Foundation(NSF). DUSEL will provide scientists and engineers with a research facility capable of supporting a broad spectrum of fundamental and applied research deep in the earth’s crust. Research partners are physicists, biologists and geoscientists. DUSEL research calls for the construction of a network of shafts, tunnels and caverns that will provide laboratory facilities at depths of up to approximately 2 kilometers. The Project is still in the planning stages but, the initial experimental program is taking shape and conceptual designs have already been developed at two hard rock mine sites. This paper discusses the overall program and key engineering tasks being developed to support the construction of deep, large-span caverns. These caverns will house a new generation of physics experiments. As currently scoped, the experiments call for the excavation of permanent caverns with spans of up to 60 meters, sited at depths in excess of a kilometer.

Jan 1, 2007

By Earl T. Hayes

THIS BIBLIOGRAPHY has been assembled to aid research by the Bureau of Mines, and others on high-purity tungsten. It appears approximately 50 years after the development of ductile tungsten-one of the first metals to be produced in a high-purity form. Requirements of the missile age are ever more demanding that engines rout hotter and space vehicles fly higher and faster. Thus, it has become necessary to reexamine all conventional materials of construction as well as to investigate new combinations. At this stage of our technology we have alloys capable of operation at 1,800° F. and several possibilities of developing some. that will be satisfactory up to 2,500° F. Strength-weight comparisons, detrimental to tungsten at, lower temperatures, disappear at this point, mid tungsten or its alloys appear to be the only metal capable of operation at truly high temperatures. The aim of this bibliography has been to include only references that concern improving the purity of tungsten-from processing the ore to treating the finished metal. In this sense it is a selected and not a critical bibliography. The period front January 1911 through February 1959 has been covered. Because repent literature has the greatest, value, most of the selected items refer to publications issued within the pest 5 years.

Jan 1, 1960

By Michel Massé

Eleonore Project- Agenda ? Purpose and Technical Overview ? SmartEXEC Control Capabilities ? SmartEXEC System Archetecture ? SmartEXEC System Advantage Eleonore Project- Purpose and Technical Overview ? Control air quality while maintaining target production levels at minimum energy operating cost ? Improve safety, work place conditions and operation flexibility ? Reduce energy consumption and green house gases footprint

Aug 1, 2013

By Richard M. Tinlin

Some of the practices of the mining industry that may place an undesirable stress on the groundwater environment are coming under increasing scrutiny from legislators and regulatory agencies. Among these practices are mine dewatering, the use of tailings ponds, land rehabilitation, and technological innovations such as in situ leaching of waste clumps and ore deposits. Pernichele, noting that 24 states have enacted legislation controlling to varying degrees the environmental effects of mining, has emphasized the importance of assessing the potential for damage to groundwater when evaluating, planning, and designing mining projects. 1 Illinois has enacted legislation requiring anyone opening, operating or abandoning a mine site to obtain a permit from the Illinois EPA. The law is one of the first to require regular monitoring and reporting to a control agency. Legislation has also been recently enacted at the national level that will have a significant impact on the mining industry; e. g., the Federal Water Pollution Control Act Amendments of 1972 (Public Law 92-500). The stated objective of this Act is to restore and maintain the chemical, physical and biological integrity of the nation&apos;s waters. Specifically, according to Sec. 102(a), the Administrator of the U.S. Environmental Protection Agency (EPA) is required to prepare or develop comprehensive programs for preventing, reducing or eliminating the pollution of the navigable waters and groundwaters and improving the sanitary condition of surface and underground waters. The definition of the terms "pollution" and "pollutant" is of particular significance to those who must comply with PL 92-500. The definitions are quite broad and include most of the adverse water quality effects of man&apos;s activities. As defined in Sec. 502(19), "pollution means the man-made or man-induced alteration of the chemical, physical, biological and radiological integrity of water." Within the Act, the list of pollutants includes dredged spoil, solid waste, incineration residue, chemical wastes, radioaetive materials, heat, wrecked or discarded equipment, rock, sand, cellar dirt, and industrial waste discharged into water.

Jan 1, 1973