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By G. V. Sullivan

The Federal Bureau of Mines examined tailings samples from 13 western copper operations to determine the potential for recovering rutile. Results showed that six of the samples contained sufficient liberated titania to be considered potential sources. One sample contained 0.75 percent Ti02 or 0.40 percent liberated rutile. Batch flotation studies developed a procedure that recovered 70 percent of the liberated rutile at a grade of 34.7 percent TiO2. Sulfuric acid leaching studies on 12 of the samples dissolved 100 to 2,200 grams Cu per ton of tailings; leaching of the slimes showed slightly more copper was dissolved, 1,800 to 3,300 grams Cu per ton of minus lo-micrometer material. Bulk sulfide flotation of nine of the samples resulted in concentrates that contained 0.38 to 2.0 percent Cu and 0.7 to 2.1 and 6.9 to 42.9 grams per ton Au and Ag, respectively.

Jan 1, 1981

By B. M. Eiter, J. Hrica, D. R. Willmer

"Mineworkers are routinely tasked with making critically important decisions about whether or not a hazard presents an imminent danger. Researchers from the National Institute for Occupational Safety and Health (NIOSH) collected formative data to investigate mine safety professional perspectives on workplace examinations, which revealed a potential gap in how mineworkers are assessing risk. During interviews, participants indicated having processes in place for what should be done once an imminent danger situation is identified. Critically, however, they report having no systematic methodology for mineworkers to use to determine if a hazard is considered imminent danger. While this is important for all imminent danger situations (e.g., failure to lockout/tagout), it is especially important for those situations that are not immediately recognizable as imminent danger. In this paper, we identify and describe, three distinct categories of imminent danger complexity and discuss potential steps that could lead to improved identification of imminent danger situations. Finally, we identify potential practices to incorporate into risk management efforts, including feedback, communication, and specialized training to increase awareness of imminent danger situations. INTRODUCTION In recent years, the metal and nonmetal (M/NM) mining sector, as categorized by MSHA, experienced an increase in the number of fatalities occurring at mine sites. From 2013 to 2015, 69 mineworkers were fatally injured; that is twice the number of fatalities that occurred in each of the previous two years (MSHA, 2015a). As a way to address this increase, the Mine Safety and Health Administration (MSHA) issued a program policy letter (P15-IV-01) suggesting that “miners would benefit from rigorous workplace examinations conducted by experienced and trained examiners (MSHA 2015b).” The goal of workplace examinations is to find hazards in the field and mitigate them before they cause injury or death to mineworkers. While it is important to identify all hazards in the workplace, it is critically important to identify those hazards that are considered imminent danger because they require an immediate response to avoid a severe or even fatal injury."

Jan 1, 2018

By James M. Barker

Marketing is the linchpin of the industrial-mineral (IM) industry. Without markets and consumers for IM products, all other associated IM activities are superfluous. The simple existence of an IM deposit does not mean that it can be exploited. A dynamic interaction between exploration (geology), mining, processing, transport, marketing, sales, and consumers is required for profits. Geology dictates the existence of a deposit, but markets dictate its development, and transportation provides the connection. This is true to such an extent that marketing commonly is called the exploration phase of IMs. Marketing is strategic and includes long-range market-development and planning activities, whereas selling is tactical and more focused on day-to-day consumer interactions. Each will help the other when properly done. Many producers of IMs have failed because of inadequate marketing skill, information, and practice. Over many years at the Montana Bureau of Mines, the many developers seeking technical assistance to find an IM deposit, but who had no marketing plan, always failed. In contrast, the few who sought assistance first on marketing, with the IM deposit to be found later, always succeeded (Richard Berg, personal communication, 1998). Marketing has many facets helped by geologists who must be aware of what marketing is attempting to do. A geologist needs to understand many aspects of IMs: location (deposits, plants, consumers), processing (specifications), transportation (truck, rail, barge, ship), competition (local, regional, national, international), substitutes, pricing, and new developments and market forces of all kinds. Some needed skills are not taught formally to geologists, so well-rounded self-education and on-the-job training are the way a geologist normally enters into IM marketing. The IM geologist generally is associated with marketing either by helping to prepare a market study or by acting on the results of one. Preparing a market study is a two-part process. The first part is relatively simple but requires a time-consuming collation of data into an IM survey (mostly past-and present-oriented). The more difficult and much more important second part entails expanding the IM survey into a market evaluation (mainly future-oriented) that emphasizes forecasting, timing, location, and specific products. A market evaluation generally boils down to formulating the right questions to ask of the right persons. One very good question to ask is, "What could be the market for this specific IM?" while thinking for yourself without excessive recourse to gossip, rumors, promoters, developers, or (at times) IM experts. The evaluation must prove that market potential exists and suggests a marketing plan. Effective marketing is an ongoing process, with the initial marketing plan modified over time, using wide and continuous input to avoid tunnel vision. Industrial-mineral markets are based either on commodity (lower-priced, basic-processing) minerals or specialty (higher-priced, value-added) minerals. IM marketing methods are either product-driven (commodity minerals), a more traditional approach, or market-driven (specialty minerals), but these are neither mutually exclusive nor is one always better than the other. Focusing too much on specialty minerals can lead to problems. A blend of commodity products with specialty products commonly lowers risk and enhances long-term profits. The highest profits occur in specialty minerals at the cost of higher risk and complexity and require intelligent marketing, versatile technical services, and creative research and development. Industrial minerals are best served by an industrial-marketing approach rather than a consumer approach. Modern industrial marketing emphasizes the consumer using the "marketing concept." The marketing concept focuses all management and operational activities on total consumer management and satisfaction similar to the total quality management approaches to excellence.

Jan 1, 1999

By F. Dehghani, M. Kebe, H. Askari-Sabzkoohi, T. Ghosh

The depletion of bauxite reserves around the world has necessitated the search for viable alternative sources of aluminum. The major non-bauxite source of aluminum is alunite [KAl3 (SO4)2(OH)6]. Lixiviation is the common industrial process to recover aluminum from alunite. Due to the presence of quartz (40%) as the main gangue mineral, this process causes the formation of Sodium aluminosilicate and Potassium aluminosilicate complexes that leads to loss of alunite, and chemical reagents. Thus, pre-concentration of alunite is required to remove the gangue minerals. Because of the low degrees of freedom (DOF) of alunite, froth flotation, as a preconcentration method, is a viable alternative to increase selectivity in downstream processes. In this work, the possibility of Alunite preconcentration with micro flotation and mechanical flotation cells was studied. The influence of type and dosage of collector, pH, solid percent, particles sizes were considered on the flotation. Flotation tests were designed based on Taguchi method, followed by performing based on surface charge differential between alunite and quartz on direct and revers flotation. In the reverse flotation, Ca+ 2 and Ba+ 2 were used to activate the quartz surface. Under optimum conditions of reverse flotation, alunite grade and recovery were 40% and 62.1% respectively. In the direct flotation, the surface of alunite was activated by F- . The grade and recovery were 50 and 89%, respectively.

Mar 2, 2022

By W. G. Prast

Best known for its extensive bauxite and alumina exports, Jamaica also has a small but active industrial minerals sector. The island has for many years been a net exporter of small tonnages of gypsum, metallurgical-grade limestone and marble products. As bauxite and alumina earnings have declined the government of Jamaica has made extra efforts to promote growth of overseas sales of these nonmetallics. The nearby U.S. market is a natural first choice for new exports. Overview In 1984, Jamaica quarried an estimated 3.2 million cu m of marble and fill and an additional 3.5 million cu m of sand and gravel, for use in domestic construction. These amounts are in line with the production in earlier years of the 1980s but are not a factor in the export pattern and need not be considered further. Similarly, annual production of 15 million ton of silica sand for the manufacture of glass bottles is principally consumed by the domestic market.

Jan 1, 1986

By N. T. Mirafuente

The device called "Dynastat" which is described in this paper provides in situ borehole measurements of dynamic and static parameters for use in a wide range of design applications. In the dynamic mode, the Oynastat allows measurement of shear and compressional wave velocities. From these velocities in situ dynamic Young's modulus and other dynamic elastic parameters can be calculated. In the static mode, the device allows measurement of load versus deformation from which in situ static Young's modulus can be determined. Information on in situ horizontal stress fields can also be estimated from the load deformation curves. In both mining and civil engineering applications, in situ measurements of material properties are indispensable for accurate evaluation of design problems. Laboratory dynamic and static test measurements in comparison to in situ measurements are often misleading due to difficulties in obtaining undisturbed samples and in accounting for effects of discontinuities, etc., for mass properties. The authors contend that among in situ borehole measurements, the method employed with the Dynastat is the most accurate and detailed technique of measurement. The Dynastat employs the crosshole method of shear and compressional wave velocity measurements and also performs as a borehole jack to obtain load-deformation relationships of materials at exactly the same location at depth in boreholes.

Jan 1, 1976

By R. P. King, M. K. McCarter, K. S. Free

Mine plans typically consider the profits and costs associated with extracting and processing minerals into marketable products. Interrelationships between mine and mill costs are often overlooked during the process of mine plan optimization. A simple and quick method for predicting milling costs for a given block would improve the planning process, especially if the procedure could be incorporated as part of routine ore grade analysis of drill core or cuttings. Incorporating milling costs as part of the mine planning process could improve overall optimization of the mine/mill combination. A method developed by the Utah Comminution Center (UCC) at the University of Utah provides a possible answer to the need for quick and reliable grinding cost estimation (King et al., 1996). Using results from single-particle impact tests, a work index, called the Utah Load Cell Work Index (ULCWI), is calculated. The potential for routine use of the new method is explored by comparing ULCWI values with corresponding Bond Work Index (BWI) values for eight mineral materials (Free, 2000).

Jan 1, 2004

By E. McCullough

"Fostering positive community relations is a principal tenet of sustainable development, but conflict can test even the strongest of relationships. While conflict surrounding resource development projects has the potential to be destructive, it may actually pose opportunities for partnership and collaboration when managed effectively. It is therefore not only important for mineral resource professionals to recognize the financial and social costs associated with legal disputes among project stakeholders, but also for them to prioritize resolving social conflict using alternative channels that allow for win-win outcomes. A variety of dispute prevention and resolution techniques do exist, but successful practice is not yet the norm. Here we review the sources and consequences of social conflict in the context of mining projects, and discuss typical and alternative approaches to conflict management in light of their respective benefits and drawbacks. We also suggest implementation of conflict resolution lessons into resource-related university curricula as a critical step in the continued shift of the mining industry towards sustainable development. INTRODUCTION Social conflict is a recurring phenomenon in the human experience and serves as a critical mechanism for change [1-5]. It occurs when two or more parties perceive that their needs and interests are in direct competition with each other and believe they cannot be reasonably accommodated. Conflict over mineral resource activities, particularly the distribution of benefit and risk, has become an omnipresent issue throughout the world [6-7]. Contrary to common perception, however, conflict can be a positive, transformative encounter in some instances [2, 8-11]. For this to be possible, society and its acting agents must reconsider how to address conflict. What if conflict were only a challenge to try something different? It is well-understood that the mineral industries must manage an increasingly significant volume of social conflict [12-13], which can be a costly externality impacting all of whom are involved. We commonly consider conflict in a two-party sense, but this deeply over-simplifies the true number of stakeholders. Besides mining companies and community members, government policymakers and regulators, public interest groups, and judicial systems, to name a few, bear the social expenses of poorly-managed conflict [4, 6, 12, 14-22]. It is desirable for interested parties to participate actively in a constructive way to pursue their needs rather than contributing to adversarial relationships, operational problems, and legal costs [1, 4, 12]. Some mining companies are of course already working to develop more productive relationships with their stakeholders, but there is undoubtedly still a gap between ideal and common practices. This gap can inhibit collaboration and threaten the potential for mutually-beneficial resolutions to complex social issues [12]."

Jan 1, 2016

By E. McCullough

"Fostering positive community relations is a principal tenet of sustainable development, but conflict can test even the strongest of relationships. While conflict surrounding resource development projects has the potential to be destructive, it may actually pose opportunities for partnership and collaboration when managed effectively. It is therefore not only important for mineral resource professionals to recognize the financial and social costs associated with legal disputes among project stakeholders, but also for them to prioritize resolving social conflict using alternative channels that allow for win-win outcomes. A variety of dispute prevention and resolution techniques do exist, but successful practice is not yet the norm. Here we review the sources and consequences of social conflict in the context of mining projects, and discuss typical and alternative approaches to conflict management in light of their respective benefits and drawbacks. We also suggest implementation of conflict resolution lessons into resource-related university curricula as a critical step in the continued shift of the mining industry towards sustainable development. INTRODUCTION Social conflict is a recurring phenomenon in the human experience and serves as a critical mechanism for change [1-5]. It occurs when two or more parties perceive that their needs and interests are in direct competition with each other and believe they cannot be reasonably accommodated. Conflict over mineral resource activities, particularly the distribution of benefit and risk, has become an omnipresent issue throughout the world [6-7]. Contrary to common perception, however, conflict can be a positive, transformative encounter in some instances [2, 8-11]. For this to be possible, society and its acting agents must reconsider how to address conflict. What if conflict were only a challenge to try something different? It is well-understood that the mineral industries must manage an increasingly significant volume of social conflict [12-13], which can be a costly externality impacting all of whom are involved. Conflict is commonly considered in a two-party sense, but this can deeply over-simplify the true number of stakeholders. Besides mining companies and community members, government policymakers and regulators, public interest groups, and judicial systems, to name a few, bear the social expenses of poorly-managed conflict [4, 6, 12, 14-22]. It is desirable for interested parties to participate actively in a constructive way to pursue their needs rather than contributing to adversarial relationships, operational problems, and legal costs [1, 4, 12]. Some mining companies are of course already working to develop more productive relationships with their stakeholders, but there is undoubtedly still a gap between ideal and common practices. This gap can inhibit collaboration and threaten the potential for mutually-beneficial resolutions to complex social issues [12]."

Jan 1, 2016

By James J. Scott

Friction Rock Stabilizers, trade name II Sp 1 it Sets'" have been under research and development by the author and the Ingersoll-Rand Company since February of 1973. The United States Bureau of Mines and the Mines Enforcement and Safety Administration as well as many mining companies have cooperated in field testing the device. Split Set rock anchors are distinctively different from the widely used mechanical rock anchors or fully grouted rock anchors. They control ground movement internally in a manner that allows controlled deformation during the early phase of the ground reaction curve but then, as secondary creep develops, anchorage per unit length increases and they serve to strengthen and stabilize the opening for long periods of time. The history of research and development of the Scott Split Set rock anchor system with accompanying laboratory and field test data is presented in this paper.

Jan 1, 1977

By D. C. Hatch

At the MacIntyre Development of the Titanium Division of National Lead Company a magnetite-ilmenite ore together with gabbro-anorthosite waste is mined from an open pit by shovels and trucks. The ore from the pits is trucked to ore stockpiles for blending ahead of the crusher and to free the mine from crusher delivery schedules. The ore stockpiles are blended to yield a 16.5 to 17.0 % TiO, crusher feed. This requires mining on an assay cut-off rather than a visual grade cut-off. Highly mineralized ore runs from 20 plus % TiO2 and 30 plus % Fe to 15 % TiO2 and 40 plus % Fe as the ratio of ilmenite to magnetite changes. There are three major ore types in the present pit with magnetite ratios varying from about one to one up to three times as much magnetite as ilmenite. Ilmenite and magnetite together liberate from gangue down to about 10 mesh and this is the basis of the magnetic cobbing. Below 10 mesh the ilmenite and magnetite start to separate and ore cobbing pulleys will not hold the ilmenite.

Jan 1, 1968

By LeRoy D. Loy

The coal mining industry must be able to compete with alternate sources of fuel for the utility and industrial customers. If the industry is unable to control transportation costs, either due to government interference, or for other reasons, then mining costs must be kept down. Australia, South Africa, Canada, (and later Colombia) will take larger shares of the export market if mining costs are not kept competitive. The government's environmental regulations must be met without incremental increases in mining costs. Entrepreneurial instincts must be retained by the industry to provide for their investment in the future. What are the Problems with Existing Research? Government funding for coal mining research has been reduced or virtually eliminated. BCR (Bituminous Coal Research) is now a membership- supported organization, but its primary focus has been on health and safety-oriented research. BCR, however, is now attempting to widen its scope and conduct other types of research. There are almost no funds in EPRI's (Electric Power Research Institute) program for coal mining research. Large mining companies do some research for their own purposes and needs, but this is proprietary and therefore results are not shared with the remainder of the industry. The mining industry as a unit is not undertaking productivity (systems) oriented research in any common or cohesive manner.

Jan 1, 1983

By Kotaro Ohga, Kiyoshi Higuchi

In our laboratory, a new detection system using smell detectors was developed to detect the spontaneous combustion of coal and the combustion of other materials used underground. Laboratory experiments were carried out on several kinds of coals, including South African coals, and machine oil, wood and rubber used in belt conveyers. The following results were obtained: 1) Spontaneous combustion of coal can be detected earlier by smell detectors than by conventional CO detection methods. 2) There were no differences in the results using different kinds of coal. 3) Combustion of other materials can also be detected earlier by this system than by conventional detectors for gas and smoke. 4) Use of this detection system enables one to discern the source of the combustion gases, whether it be coal, wood, oil or rubber.

Jan 1, 1995

By H. Cho

A study was undertaken to investigate the liberation behavior of coal macerals through size reduction and density separation. It was seen that the liberation of coal organic components could be achieved by size reduction, allowing selective separation of coal organic components. However, the degree of liberation is dependent on the history of coal: the extent of liberation decreased when the size of the primogeniture coal decreased. The liberation of coal macerals was analyzed by examining the Liberation Index. It was seen that although comminution produced fine particles enriched in inertinite (primarily fusinite and semifusinitie), these particles were less liberated than the coarser particles. However, the liberation of macerals increased when all the feed was ground to a finer size.

Jan 1, 1996

By M. Ploc

The grinding process in the mining industry has seen an increased throughput to accomplish greater production and lower overall production costs. Up to 8-9 MW, a single motor can be connected to drive the mill through a pinion and ring gear. Above the single-pinion drive limit, the dual pinion approach was developed to allow two drive motors to be used. This allowed the mill input power to be increased to 16-18 MW. Recent developments in clutch and ring gear materials and design are allowing greater input powers of up to 20 MW to be considered. To avoid damage to the ring gear by uneven load sharing between the two motors, it is critical that the two machines accurately share load. This is typically achieved by either drives capable of controlling load torque between motors or using a GE proprietary control system that accurately controls the load torque from each motor.

Jan 1, 2010

By MARK J. VANARELLI

Estimating groundwater inflows in rock deep tunnels is critical to the safety of personnel constructing the tunnel and the cost of construction. This paper presents two case studies for estimating steady-state groundwater inflows into deep rock tunnels. The case studies included the Chattahoochee and Nancy Creek tunnels. In this paper, statistical methods were applied to packer test data obtained from exploratory borings during geotechnical site investigations. A semi-empirical procedure was utilized for estimating groundwater inflows into these deep rock tunnels. The Chattahoochee and Nancy Creek tunnels are deep rock tunnels which exhibit radial flow conditions. For the radial flow condition, a statistical analysis presented in this paper indicates that the semi-empirical procedure works well; however, variations in the procedure and/or an insufficient amount of testing could lead to underestimations of the inflow quantities. Packer test data plotted in histograms were observed in all cases to be log-normally distributed for the radial flow condition. Modeling using Monte Carlo simulations was observed to be an effective tool for removing irregularities in the distribution of the data and incorporating high-end permeability data to derive reasonable groundwater inflow estimates.

Jun 13, 2021

By M. Canty

Results are presented that were gathered during pilot-and field-scale testing of an innovative technology, sulfate-reducing bacteria (SRB), designed to treat and control acid mine drainage (AMD). The project was performed under the Mine Waste Technology Program (MWTP), which is funded by the U.S. Environmental Protection Agency (EPA) and jointly administered by the EPA and the U.S. Department of Energy through an Interagency Agreement. The MWTP is implemented by MSE, Technology Applications, Inc., located in Butte, Montana. Sulfate-reducing bacteria, a common group of anaerobic bacteria, produce hydrogen sulfide and bicarbonate when supplied with sources of carbon and sulfate. Hydrogen sulfide reacts with metal ions in AMD, precipitating them as metal sulfides; the bicarbonate serves to help neutralized the drainage. Pilot-scale testing was performed within eight packed-bed reactors at a temperature representative of a field application of this technology in a northern climate, nominally 8°C. The reactors, packed with an organic substrate, were operated continuously in upflow configurations receiving AMD at a flow rate corresponding to a 5-day retention time over a test duration of 60 days. During this time, numerous physical and chemical parameters were monitored. Pilot-scale metal removal efficiencies reached 99% for zinc, 99% for aluminum, 96% for manganese, 98% for cadmium, and 96% for copper. Iron and arsenic removal was not as effective as the aforementioned metals, which was largely attributed to the high levels of iron and arsenic contaminating the organic substrate. Evidence existed that both adsorption and sulfate reduction were occurring within the reactors.

Jan 1, 1998

By James M. Griffin

Ladies and Gentlemen, There have been no less than ten major coal project financings in the last eighteen months. Each of these has been in the order of $100 million to $1 billion for the development of a coal property and its associated infrastructure. It is appropriate at this time to review the nature of these past financings. Why has there been so much activity? There are primarily two reasons. The first is due to the large number of contracts which were signed as a result of OPEC oil shocks. High projections were made for increased coal consumption particularly in world trade. This is distinct from domestic coal mine/power plant projects which often tap a government source of funds. Second is the high cost of coal development in the 1980's compared with a typical company's corporate borrowing capacity.

Jan 1, 1984

By R. E. Nivens

In the past, Newmont Gold Company relied on cement for their ore agglomeration process. With assistance from Betz Industrial, Newmont began Investigating the use of polymers for ore agglomeration. If gold recovery would not be jeopardized, then polymers could replace cement and possibly reduce operational costs associated with cement agglomeration. The following outlines the preliminary testing conducted to determine the feasibility of polymer agglomeration with Newmont's ore and the results of the test heap, which was constructed so the program could be examined under actual operating conditions. Similar polymer agglomeration testing has been successfully performed in other Nevada gold operations. By eliminating the need for cement, a polymeric agglomeration program could improve material handling operations, as well as offer the following additional savings. First, the polymer application uses only lime for adjusting basicity, the polymer does not contribute any alkalinity to the heap. Because lime is more soluble than cement, detoxification of the heap becomes much faster and less costly for the mine relative to rinsing cement alkalinity. The following graph compares the detoxification rate of cement and polymer over a 33 day cycle.

Jan 1, 1993

By Donald Towse

Portland cement is a basic building material in every country in the world, and, fortunately, the raw materials required in its manufacture are widely distributed. It is a low-priced bulk commodity (price one cent a pound or less, with a density of 100 pounds per cubic foot.) Table 1. Approximate price per pound of selected mineral products. Copper 48 cents per pound Aluminum 27 Lead and zinc 15 Asbestos 3 to 18 Pumice 6 Sulfur 2 Bauxite (abrasive) 1.8 Barite 1 to 1.6 Cement 1 Primitive regions may get along without any Portland cement, but most countries use some, and it is one of the most widespread building materials, even if used in small quantities. Use of cement begins early in a country's development, and, because of local availability of raw materials, cement manufacture is one of the first heavy industries many countries desire. Use and manufacture of cement usually precedes other industrial materials such as steel and heavy chemicals, and consumption levels off for a long period during development of infrastructure and an economic base. With a mature economy comes a very high consumption. Per capita consumption varies ten times or more between nations (Figure 1).

Jan 1, 1970