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By Bruce Cavender

Production managers look to innovative practices and equipment to reduce operating costs and improve efficiency. These innovations apply to both technical and social aspects of production operations and may be high-tech or low- tech in nature. They may be based on the implementation of a few large-scale "breakthrough projects or numerous small-scale activities, depending on the availability of capital funding and the company's past experience. Successful managers systematically identify innovative opportunities that capitalize on their organization's expertise. They quantify the associated benefits and risks and then manage the implementation of selected innovations to minimize cost and uncertainty. They monitor the results of the innovation after it has been implemented and adjust operating and managerial practices as necessary to maximize the innovation's benefit.

Jan 1, 1998

By Kenneth R. Dickson, I. Michael Gowring

This paper describes the underground work associated with the North Fork Stanislaus River Hydroelectric Development currently being constructed by Sierra Constructors for the Calaveras County Water District in California under a turnkey contract. Sierra Constructors is a joint venture of the Guy F. Atkinson Construction Company (sponsor) of South San Francisco, and the Harrison Western Corporation of Denver. Notable features of this project include the exceptionally high performance achieved by the 5.5m diameter Robbins tunneling machine and the 675m deep shaft pilot hole which was successfully realigned using oilfield directional drilling techniques. Other features include 3.7m and 4.3m diameter machine-excavated tunnels and various conventionally excavated tunnels constructed over a wide geographical area and diverse climatic conditions.

Jan 1, 1987

By Anand Kumar, Debasis Deb, V. N. S. Prasad. M, A. K. Mishra

Shield leg pressure data from all shields and shearer locationwith time stamp from a mechanized longwall face are monitored and recorded in a surface computer. These data contain random noise due to power failure, leakage of legs, bad sensor reading and other maintenance or geo-mechanical problems. An algorithm is developed to detect mining cycle parameters such as setting and final pressures and duration of the cycle from these data for the analysis of periodic roof weighting phenomena. The intensities and persistence of periodic roof weighting are the vital information to the mine management to take judicious decision on longwall operation. The paper presents details of the algorithm which identifies 96% of mining cycles from the noisy data belonging to consecutive 5 months or 410 m of face advancement. Based on this analysis, 2 types of periodic roof weighting phenomena are detected, namely, (i) normal type—having peak intensity of 75 to 90% of yield pressure, interval of occurrences of about 10 to 15 m with persistence of 3 to 4 m and (ii) severe type—peak intensity over 90% of yield pressure, interval of 25 to 40 m with persistence of over 10 m. It is envisaged that these phenomena have direct relationship with main roof thickness, its overhung length and material properties.

Nov 19, 2020

By M. K. Boateng, K. Awuah-Offei

"Mining companies have started using quantitative tools, including computer models of community interaction, to gain intelligence on social risks surrounding their projects. Models of changes in community preferences regarding mining projects over time are useful for evaluating changes in project risk due to changes in the social license to operate. For example, agent-based models that use information diffusion models and social networks are useful for studying those changes due to information diffusion. However, such agent-based models are sensitive to many input parameters including the parameters of the diffusion model and the average degree of the social network. This work evaluates the sensitivity of such a model to diffusion and network model parameters (probability of imitation, probability of innovation, and average degree) using the first order and total sensitivity indices. The results show that the model is much more sensitive to the probability of imitation than the other two parameters. Thus, to reduce uncertainty surrounding the model’s predictions of community acceptance of mining, mines need to obtain accurate estimates of the probability of imitation. INTRODUCTION Mining companies have started using quantitative tools, including computer models of community interaction, to gain intelligence on social risks surrounding their projects. Models of changes in community preferences regarding mining projects over time are useful for evaluating changes in project risk due to changes in the social license to operate. For example, agent-based models that use information diffusion models and social networks are useful for studying those changes due to information diffusion. However, such agent-based models are sensitive to many input parameters including the parameters of the diffusion model and the average degree of the social network. This work evaluates the sensitivity of such a model to diffusion and network model parameters (probability of imitation, probability of innovation, and average degree) using the first order and total sensitivity indices. AGENT-BASED MODEL OF COMMUNITY ACCEPTANCE A few researchers have started using agent-based models to study mining systems (Fujiono 2011; Nakagawa et al. 2013; Bahr 2015; Boateng and Awuah-Offei 2017a, b). Nakagawa and co-workers used ABM to evaluate dynamics of a mining project’s stakeholder networks whereas Fujiono used ABM to study innovation diffusion in the mining industry. Our previous work has presented models and a framework for modeling information diffusion in a mining community and its impact on level of acceptance (a measure of SLO) of the mining project (Boateng and Awuah-Offei 2017a, b)."

Jan 1, 2018

By Malcolm Heyburn

Airborne and ground magnetic surveys were made over and in the vicinity of the Sanford Hill ore body at Tahawus, Essex County, New York. These geophysical surveys served to: l. delineate, lithologic and structural features associated with the ore bodies; 2. indicate a major extension of the Sanford Hill ore body; and 3. guide a drilling program to prove this extension. The titaniferous magnetite ore body at Sanford Hill is associated with gabbro occurring in anorthosite. The contrast in the magnetic susceptibilities of these rock types, reflected in the magnetic measurements, allows geologic-mapping showing rock types and inferred structural features. The anomalous magnetic high of the airborne magnetometer survey indicated a southern extension of the Sanford Hill ore body. Diamond drilling, guided by the airborne and specifically the ground magnetic results, substantiated this interpreted ore extension to be of major magnitude.

Jan 1, 1961

By J. L. Roll

The Surface Mining Control and Reclamation Act of 1977 (SMCRA) and the regulations promulgated for that "Act" have resulted in changes to surface mining operations in order to comply with the stringent federally enforced reclamation requirements for prime farmland. In many instances the operator has modified surface mining operations to meet the prime farmland requirements through changes to mining equipment operation, addition of new equipment targeted for reclamation or the use of totally different mining techniques. The major challenge to mine operators has been how to use existing mining equipment to meet the requirements of the "Act." Freeman United Coal Mining Company opened the first new large surface coal mine in Illinois following passage of the "Act." The Industry Mine, located near Macomb, Illinois started mining operations during March of 1982 and was required therefore, to meet all of the requirements of the "Act" including prime farmland restoration. At the Industry Mine a shovel and a cross-pit bucket wheel excavator (wheel) are used for overburden removal and the wheel is addition- ally utilized to assist in reclamation operations. The wheel mines the subsoil thereby elliminating scraper placement of that subsoil and the attendant compaction problems with scraper placed subsoil. The wheel is used to convey topsoil stock- piles from the highwall to the mined overburden in order to lessen scraper traffic and possible compaction on the graded overburden during top- soil removal and replacement. Close control of the operation of the wheel yields more uniform wheel spoil ridges which then require less grading prior to topsoil replacement.

Jan 1, 1986

By V. F. Hollister

Although it is apparent that porphyry copper deposits may have formed in the Andean orogen from Permian time onward, commercial deposits thus far developed appear to have Cenozoic ages only. Following Chilean useage, the porphyry deposits are divided into either: (a) a stockwork, or (b) a tourmaline breccia model. Stockwork type deposits tend to occur on major strike-slip structures which may be either transcurrent or transverse faults related to plate movements, while the tourmaline breccia type may more frequently form independently of regional faults. Stockwork types may be conjugate fractures that intersect and ramify as a network of veins and veinlets, cutting altered rock, and genetically related to a major regional fault, or in other cases they may reflect the intersection of two large fault structures. Circular fracture patterns may more rarely occur in stockwork deposits in response to a specific intrusive. Tourmaline breccia types are characterized by circular and radial fractures genetically connected in some way with tourmaline breccia pipe development or an intrusive piercement that preceded it. Each structural model contains mineralized intrusive8 which have a close time-space relationship to ore and in each model, mineral paragenesis is similar, regardless of age or location in the plate. Also, each model contains the same type of alterntion halos (phyllic, argillic, prophllitic) as are developed in intru- sive centers in porphyry copper deposits found in North America. The potassic zone is exposed best in the older deposits. Examples of each type of deposit are illustrated, demonstrating the feature evolved.

Jan 1, 1973

By J. Kretschmann, A. Müterthies, T. Rudolph, C. Yang, P. Goerke-Mallet

Catastrophic failures of dams and tailing storage facilities (TSF) have triggered the development of integrated ground monitoring concepts for hazard assessment, risk management and public safety. These concepts are based on knowledge and expertise of persons technically responsible for TSF. The aim is to combine this implicit and explicit knowledge with the data of in-situ- and remote sensors. Risk management for TSF must include a comprehensive monitoring program that integrates data from ground based-, air-borneand satellite-based sensors. Researchers at Technical University Georg Agricola (THGA) in Bochum, and EFTAS, Muenster, Germany, are fusing a variety of sensor data to enhance the capability and performance of TSF monitoring to ensure public safety downstream of TSFs. This paper describes the variety of sensors implemented in numerous research projects. It gives an outlook in terms of planned satellite missions with innovative equipment like hyperspectral sensors. The implementation of the data of these sensors in the analysis will increase the understanding of spatio-temporal impacts of mining activities. Future opportunities are explained by a datacube approach.

Mar 2, 2022

By Reed S. C. Rogers

There is recent evidence that high frequency screening can be a viable alternative to hydrocyclone classification for a wide variety of grinding applications. However, since high frequency screening is a relatively new development, the decision to use screens generally must be based on full scale screening tests of a slurry material of interest. In this paper the authors employ mathematical simulation models as an aid to evaluating the use of screens versus hydrocyclones for closed circuit fine grinding. This approach is validated in a pilot plant study and then demonstrated for the design of full-scale grinding circuit, including classifier cost comparisons. For the case of maximum production rates versus product size, without a constraint on fine product solids densities, results indicate that screening with Derrick sandwich type cloths can give higher grinding circuit production rates with more narrowly sized products than when hydrocyclones are used. These results are explained in terms of the bypass and Sharpness Index of the respective classifier partition curves. Classifier cost comparisons for the full scale circuit show that although the installed cost of screens is substantially higher than equivalent capacity hydrocylone operations, even modest increases in circuit capacity caused by screens; can significantly reduce total grinding costs.

Jan 1, 1985

By A. L. Slaughter

A mineral deposit has been discovered and explored sufficiently to establish the presence of ore in ?commercially marketable quantities," This is the point at which exploration ends and development begins, Of course, when the presence of commercially marketable quantities of ore are thought to be present the deposit had to be evaluated before this decision could be reached. If, on the other hand, it was thought that commercially marketable quantities of ore are not present, either more exploration has to be done or the project must be abandoned. It is this decision with which this paper is concerned, more particularly, the influencing factors behind this decision. The final question to be answered is: what profit can my company reasonably expect to make by developing this property and putting it into production? The answer must be expressed as a figure for final profit per ton, money which can be used to pay dividends or to build up cash reserves. Some acquisition cost has probably been paid and the exploration cost incurred at the time of decision, (abandonment or development). In addition to returning these acquisition and exploration costs, the deposit must pay development, mining, milling, capital expense of new plants and equipment, taxes, and various other related costs.

Jan 1, 1958

By Theodore H. Budd, Austin M. Cooney

The paper discusses the background and theories of the conditions that led to the settlement of a Lovat TBM mining in an earth pressure balance mode on a recent project in Milwaukee, Wisconsin. The settlement occurred independent of human error and caused the cost of the project to increase 50 percent. The project was mined in the highly congested downtown area in alluvial and estuarine deposits, 7.6 m below the water table with a prescribed contract requirement that precluded dewatering in deference to concern for foundations of adjacent existing buildings.

Jan 1, 1989

With mine activity dating back to 1792, the Lehigh Valley, about 80 km (50 miles) northeast of the historic Allentown/Bethlehem steel mills and about 160 km (100 miles) northeast of Philadelphia, PA, defined early-day coal mining. Coal mining began just nine years after the end of America?s Revolutionary War. The high-carbon, clean-burning anthracite coal that was hand-dug from the Pennsylvania hills fueled the steam engines that powered the Industrial Revolution, helping build early steam ships and even the first automobiles. Around 1910, at the peak of the U.S.?s early mining effort, there were more than 250,000 men working underground ? 10,000 of them in the Lehigh Valley.

Jan 1, 2012

By K. Awuah-Offei, A. U. Rehman

"Information diffusion potential of a social media user affects how quickly information about a mineral project can diffuse through that user. If management can use social media and network analysis, in community engagement program, to understand how fast and how far information will diffuse to communities and followers of particular social media users, it can selectively focus on the most influential users. This paper proposes a method to examine the information diffusion potential of social media accounts. The work uses Gephi, an open source software, to extract and analyze data from different Twitter handles to predict their information diffusion potential. The work uses case studies of real Twitter users (e.g. mining news organizations and bloggers) associated with mining to illustrate the approach. The case study results show that there are significant disparities in information diffusion potential that will demand selective attention. This research will help mines develop effective social media engagement strategies. INTRODUCTION The mineral industry provides raw material for industrial activity to support our society (Martens and Rattmann, 2001). Mines have changed conventional mining practices to sustainable ones because of the negative impacts of mining and increased public awareness (Wang et al 2016). The concept of sustainable mining is getting mature as stakeholders (e.g., governments, investors and host communities) are getting involved in mining projects (World Economic Forum, 2014). The failure of mining companies to address the demands of these stakeholders might result in failure to acquire social license to operate (Thomson and Boutilier, 2011). The social license to operate (SLO), if granted, is mutually beneficial to all stakeholders. Mines prefer being granted SLO and keeping it to avoid any kind of social unrest due to their operation (Prno, 2013; Moffat and Zhang, 2014). Mining communities can grant different levels of SLO; ranging from withholding SLO to psychologically identifying with the project (Joyce and Thomson, 2000; Thomsan and Boutilier, 2011). Most of the previous work to understand community perceptions and SLO in mining is generally qualitative (ICMM, 2012a; Thomson and Boutilier, 2011; Prno, 2013; Moffat and Zhang, 2014; IFC, 2014). In particular, there is limited work on how community perceptions change over time due to information diffusion (Boateng and Awuah-Offei, 2017). However, SLO changes with respect to time (Yates and Horvath, 2013), which can result in risks that are not easy to predict. Mine managers and engineers have a desire to understand these changes so as to mitigate these risks (Que and Awuah-Offei, 2014; Que et al., 2015)."

Jan 1, 2018

By Abb Raymond

Finely processed industrial minerals in "powdered" form have long been utilized by the plastics, paint, rubber, paper, ceramics, and adhesives industries as fillers, extenders, coatings and special additives. These minerals, primarily calcium carbonate, talc, kaolin, titanium dioxide, and the like, have provided economic, uniform and consistent base materials which have, in turn, been used by the referenced industries to manufacture quality products. The focus of this paper will be the development of equipment and systems at ABB Raymond for the dry processing of such non-metallic minerals in order to meet what have become increasingly stringent requirements of the producers of these minerals. Changes in these requirements seem to have been accelerating rapidly during the last ten years, and it is expected this process will continue into the 1990's.

Jan 1, 1990

By William T. Barrett

It is said that Thales of Miletus, 600 B.C.,1 was aware of the attraction of lodestone toward iron and highly magnetic minerals. However, the birth of magnetic concentration followed shortly after the invention of the first electromagnet by Sturgeon in 1825. Sturgeon's magnet was described in the annals of electricity.2 The first attempts to concentrate minerals by the use of magnets date back to about 18473 but the first commercial drum-concentrator was apparently invented by R. Cook in 1849. Credit must also be given to the invention of P. Righter's machine in 1867,5 and to the highly successful Wenström separator devised in Sweden in 1883.8 Since the advent of these early separators there have been virtually hundreds of patents granted covering minor modifications of drum-type magnetic separators. The more important advances from a technological viewpoint have been the design of stable power supplies for d.c. magnets, the advent of ceramic permanent magnets which are now replacing electromagnets for the concentration of ferromagnetic minerals, and advances in general magnet and machine configurations.7 One of the problems facing both the designer and the user of magnetic separators is the evaluation of the body forces acting on particles in the magnetic field of the separator. Perhaps the most elegant method of evaluating the body force associated with a drum-type magnetic separator is that recently suggested by W. F. Brown.8 Brown measures the radial component of the field intensity one-half inch from the drum surface and fits a Fourier series in the angle about the drum axis (Figure 1). Once the coefficients of the series are known, it is then possible to calculate [ ]

Jan 1, 1970

By Clarence Hardy Long

In January of 1969 the United States Department of Health, Education and Welfare, through the National Air Pollution Control Administration, published a series of Air Quality Criteria (4'S) and Control Techniques (6,7) for air pollutants in compliance with the 1967 Clean Air Act which will affect the operation of all fuel burning equipment in the very near future. The design of equipment for the future which will use fossil fuels will also be affected. The purpose of this paper is to discuss some of the modifications which might be anticipated in the future for fuel burning equipment. One class of the several air pollutants looked at first by the USDHEW was the sulfur oxides. Other pollutants, such as nitrogen oxides, will be studied and controls for these will supposedly be written in due time. The obvious use of low-sulfur fuels, coal, oil and natural gas is suggested by the Control Technique(6). Conversion to other sources of power, such as nuclear energy and hydropower, is also suggested. The statement is made that since possible hydroelectric sources are limited and nuclear plants are not yet available on a large scale, the changeover to these sources of power will not be overnight. The bulletin (6) suggests that one possible solution in some areas may be the use of low sulfur coals for short periods of time during periods of severe air pollution. A curve showing the effect of this was given in the 1969 April issue of the Power magazine, where A. E. Boyer and F. B. Kaylor of Stone and Webster also described a computer program called DOSAGE which might be used to check weather, temperature, humidity, wind direction and velocity, and sound an alarm when that 0.1% of the time per season is here that requires the use of low-sulfur fuel. Inversion is eminent! Once this has passed operation on regular fuel may be resumed. This would mean a separate storage

Jan 1, 1970

The Montgary pegmatite is located at Bernic Lake in the southeastern Manitoba pegmatite district. 'It has a complex internal structure with several contrasting mineral assemblages. The pegmatite contains a number of potentially valuable miners including spodumene, amblygonite,. lepidolite, zinnwaidite, pollucite and beryl.. The distribution of each of these within the pegmatite is related to the internal structure and controlled by a specific mineral assemblage. Parts of the pegmatite contain a high concentration of spodumene. The pollucite occurrence is of unique character and is one of the largest known deposits of this mineral. The pegmatite is still-like in attitude with a maximum dip of about 15 degrees. Its contents with the amphibolitic wall rocks are sharp and tourmalinized. Mineral assemblages present include perthite-plagioclase-quartz-muscovite, spodumene-microcline perthite-plagioclase-quartz-muscovite, cleavelandite-lithia micas-quartz, quartz-amblygonite, albite, lepidolite, pollucite, and quartz assemblages. The occurrence and relationships of these are described and possible relationships between attitude and internal structure are discussed. Many features of the pegmatite suggest that the deposit formed by crystallization and differentiation of a pegmatitic fluid in a restricted system. These features are discussed. The nature and occurrence of the pollucite, lepidolite and albite assemblages are such, however that it is difficult to visualize them resulting from such a system. These assemblages may be of later replacement origin. The source of the, late, alkali-rich replacing solutions may be unmixing of soda and the rarer alkalis (lithium, rubidium, caesium) from earlier-formed silicates in a manner analogous to the unmixing of soda feldspar in perthites. Various aspects of this hypothesis are examined.

Jan 1, 1959

By Jerry C. Tien

The rare earth elements (REEs) are a group of 17 chemical (metallic) elements which appear in the periodic table. The group consists of 15 lanthanide elements along with yttrium and scandium (Table 1). They share many similar properties, which is why they occur together in geological deposits. Although commonly referred to as rare, they are really quite common; the reason they are perceived as rare is because it is not common to find them in commercially viable concentrations. These metals are critical to advanced technology, ranging from smart phones to global positions system (GPS) receivers, medical devices and jet engines. They are critical in green, high-tech and defense industries (Fig.1 and 2). Although there have been increasing efforts to find alternative supplies, these efforts have been complicated by the pollution that rare earth mining and processing creates. To extract rare earths minerals from mined ore is a complicated and costly process. The ore is first mined through normal mining process, the bastnaesite, which generally contains a number of minerals of little value, is first removed through a floatation process. The bastnaesite containing the REEs is further separated into their respective pure forms in a separation plant using acid and various solvent extraction separation steps. Each element has its own unique extraction steps and chemical processes. At times, these elements, in the form of oxides, will require reprocessing to achieve ideal purity. The last steps would be to further process into metals first, then alloys for various applications. The entire process takes approximately 10 days. The mining and processing of REEs, if not carefully controlled, can create environmental hazards. This is one of the reasons the Mountain Pass Mine in California was closed down in the 1980s.

Dec 1, 2013

By K. H. McDaniel, L. Griswold

The Waste Isolation Pilot Plant (WIPP) is adding a third fan to supplement its two existing main fans. The third fan will operate in parallel with the two existing fans. An engineering analysis conducted in 1995 identified the need for improved system availability and efficiency. The WIPP, located near Carlsbad, NM, is a US Department of Energy (DOE), Carlsbad Area Office, facility that is designed to permanently dispose of US defense-generated transuranic waste in a deep, bedded salt deposit. Engineers at the WIPP performed a feasibility analysis for modifying, supplementing or replacing its two main mine fans. Since the centrifugal fans were installed in 1988, multiple operational and performance concerns have been identified. A comprehensive engineering study was conducted (McDaniel et al., 1997) to identify and quantify operational concerns, evaluate possible alternatives and recommend an optimum solution. The study indicated that adding a third single-duty centrifugal fan similar to the two existing fans and equipping that fan with Inlet Van Controls (IVCs) was the best choice. This alternative provided the most desirable combination of operational readiness and improving system performance. The fan installation project accommodates several operational and scheduling con¬straints. WIPP was scheduled to receive waste in May 1998. This milestone is proceeded by an operational readiness review. Fan installation could not be allowed to compromise the WIPP 's ability to declare facility readiness. Therefore, operational disruptions during the system tie-in had to be minimized. All engineering for the project has been com¬pleted, and physical modifications were begun in July 1997. The project was completed in 1998.

Jan 1, 2000

By Dan Witkowsky

In an increasingly environmentally conscious world, mining's importance to society has often been misunderstood and even maligned by the public. Extreme and impractical ideas have often been presented to children because of the lack of accurate, timely resource materials available to educators. In the late 1960s. two mining engineers, S.P. "Pi" Warren and C.L. "Lindy" Barker, became aware of this situation. They proposed to develop a summer field course to provide a factual overview of the minerals industry for teachers. The pair believed that teachers could become better informed to educate students, and future generations, about mining. These two Colorado Mining Association (CMA) members felt that such a course could reduce much of the misunderstanding about this vital industry. This could be done by providing a balanced perspective of mining, not only for kindergarten-through-grade-12 teachers, but also for the students they would be teaching during their careers. Students who better understood the minerals industry could better formulate an unbiased view of it. The course would seek recognized authorities from industry, academia and government who would lecture in their respective fields of expertise. The course would provide a total concept of the coal, aggregate, metals and industrial minerals industries. It would include geology, geophysics, exploration, mining, processing, marketing, product applications, economic, mining history, careers, and environmental responsiblity. When possible, site visits would permit educators to view operations and to meet the men and women who are industry leaders. Teachers would pay a small tuition fee. The balance of the program expenses for each teacher would be paid through scholarships provided by industry and individuals. The "total concept" idea obtained the support of the minerals industry. The support of CMA's Education Committee and the Colorado School of Mines (CSM) was obtained in 1968. Colorado's Commission on Higher Education approved teacher recertification credits through CSM's Office of Special Progams and Continuing Education for those successfully completing the program. The first six-week series of classes presenting the total concept of the indus¬try was held at CSM in 1969. In 1977, the CMA Education Foundation Inc. (CMAEF) was established as a Colorado nonprofit corporation. The "Total Concept of the Mining Industry" (Total Concept) course was placed under its sponsorship. CMAEF is dedicated toward this continuing education program (Table 1). In 1994, the course was streamlined to four-weeks for six hours recertification credit.

Jan 1, 1997