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By Phillip J. Maddex

After the presentation of a co-authored paper, "The Cost of Transporting Ores and Raw Materials in World Markets", at the February SME meeting, one questioner commented, "You have been talking about the large shipper and ship loads. What does the small shipper do?" This paper will attempt to answer that question, at least in part. Probably the questioner hoped to hear about specific new tools and new techniques that he could apply. But one paper could only scratch the surface of the vast fund of information available; so rather than talk specifics we should take basics, that is, people, management and technology.

Jan 1, 1967

By A. Norholm

For grinding Portland Cement, the power consumption accounts for some 35 % of the total consumption of electrical energy for producing cement, counting right from the quarry to the packing plant. It is therefore for very good reason that great efforts during the past years have been put into making cement grinding more efficient, thereby saving power. In this paper three ways of reducing the consumption of electrical energy will be described, namely precrushing in the high pressure FLS-Köppern roller press, the introduction of a new design of COMBIDAN diaphragm in ball mills and the separation of mill discharge in the newly developed high efficient; separator SEPAX from F. L. Smidth.

Jan 1, 1987

By Jack M. Campbell

The regulatory process by which governmental authorities acknowledge and, in turn, permit the location, construction, and operation of large scale energy-related facilities has become extremely detailed in recent years. One example of the detail that is entailed in the regulatory process is the number of permits that must be acquired by operators prior to the construction and operation of energy-related facilities. It has been estimated, for example, that 75 permits are required prior to the opening of a new coal mine in Pennsylvania while 50 are required in Kentucky. From the perspective of facility owners and operators the regulatory process often appears overly complex and may be perceived as a constraint to the corporate decision making process. From the perspective of those responsible for administering regulations, the process is perceived as a mans by which public desires - pursuant to social objectives such as environmental protection and occupational safety - can be achieved. As a result of conflicting organizational interests, the clash between energy facility owners and operators and their regulators appears to be inevitable. Furthermore, the resolution of this conflict lies in the tradeoff between objectives and the costs of regulation. The balance of objectives and costs is a subject of the political process and not a topic of consideration in this paper. This paper is concerned with the actual administration of regulations, that is, the implementation of that which arises from the interplay of organizational interests. The paper assumes that environmental control laws will not likely be repealed, that regulations to implement the intent of these laws are here to stay and thus the paper seeks to assess how regulations are administered at various levels of government pursuant to objectives. The paper hypothesizes that the administration of objectives (or policy) has an impact on decision making which affects energy facility decision; making while recognizing the fact that regulatory policy cannot be totally divorced from administration, this paper proceeds

Jan 1, 1977

By John A. Organiscak

The Bureau of Mines evaluated a new dust control technique for longwall personnel required to work at the tailgate end of the face. This technique utilizes a water-powered scrubber to clean a portion of the face air, which is discharged behind a brattice partition at the working area. Laboratory simulation of this system in a wind tunnel resulted in average efficiencies greater than 70 pct with system efficiency directly related to scrubber quantity. Underground evaluations indicated a similar direct relationship between scrubber quantity and system efficiency. Gravimetric measurements of respirable dust made during these underground evaluations resulted in average protection efficiencies ranging from 30.7 to 42.5 pct with increasing scrubber air quantity.

Jan 1, 1983

Innovative mining technology came to Texas in the form of bucket wheel excavator/cross-pit spreader systems. Texas Utilities Mining Company put the first system to work at its Big Brown Mine in December 1985. The second such system was put into operation at the Monticello Mine in February 1991. The cross-pit spreader systems are mobile, electrically powered, excavation and conveyor systems, the principal components of which include bucket wheel excavators (BVE) and an across-the-pit conveyor (spreader). These crawler mounted machines operate as a unit; the BVE's excavate overburden, feed it via conveyors to the spreader which in turn conveys the material across the open pit and onto the developing spoil bank. The system at the Big Brown Mine is composed of 2 BVE's and an across-the-pit conveyor while the Monticello system is made up of 1 BVE and a spreader. The BVE's prestrip overburden preparing a dragline bench for the final removal of overburden. Numerous evaluations, including lignite production requirements, economics, overburden characteristics, rehandle reduction, spoil stability, and the compatibility with dragline operations, led to the selection of the cross-pit spreader system at the Big Brown Mine. The system has proven itself as a viable and economical means of prestripping. The system's success at the Big Brown Mine led to the development of a second such system at Monticello. The advent of the cross-pit spreader system is viewed by Texas Utilities Mining Company as a viable solution to recovering deeper lignite reserves in a safe and economical manner.

Jan 1, 1993

By D. C. Yang

A packed column jig has been developed for sharp separation of fine particles--150 down to 1 micron--having different densities. The packed jig is a column filled with corrugated packing. A slurry of mixed particles is fed into the middle of the column. Water enters near the bottom of the column as both a steady state and a pulsating flow. The pulsating water sets up a jigging action that interacts with the packing causing the dense particles to sink and exit the bottom of the jig and the lighter particles to rise and exit the top of the packed jig. The result is a sharp, environmentally friendly, gravity separation machine with low operating costs. Grades and recoveries of iron ore exceed that of known devices. Grades as high as 95 percent purity with concomitantly high recoveries are common for iron ore concentration. Low silica, sulfur and phosphate are common. This paper is the first to unveil the packed column jig technology in detail and presents its physical model with performance data. The purification of iron ores and coal is the paper's focus.

Jan 1, 1997

By Tedd B. Bodimer

Why complicate an already complex machine such as a continuous miner by adding roof drills? Immediate permanent roof support is an immediate thought of the mining engineer just as elimination of frequent time-consuming places changes is a thought of the methods engineer. The realization of those two objectives has the potential for improved safety with increased production is the thought of the general manager. Miner-Bolters Used a Generation Ago These are not new thoughts as the 1CM continous miner equipped with two integral roof drills was introduced twenty-five years ago. Approximately two hundred of these machines were sold in the next five years for use in medium and high seam operations. The 1CM miner chassis that remained stationary in the center of an entry or room while the ripper bar was swung and sumped hydraulically provided an ideal platform for mounting two roof drills that could be operated during the continuous miner's production cycle. Two roof bolts could normally be installed in less time than required for the mining cycle. A typical roof drill unit is shown in Figure I.

Jan 1, 1981

By Max Friedemann, Alexandros Bousdekis, Anna Gustafson, Helmut Mischo, Håkan Schunnesson

Many devices used in mining are not monitored by sensors or do not have their own intelligence. By retrofitting sensors and real-time data processing, machines can be integrated into an existing digital infrastructure. Within the project Mine.io funded by the European Union a Sandvik DE110 exploration drill rig is being digitized using various AI algorithms at research and education Mine “Forschungs- und Lehrbergwerk Reiche Zeche (FLB)” of TU Freiberg. The aim is to increase the productivity of drilling with real-time evaluation of the current rock to be drilled and the current maintenance status of the drill rig. The drill rig is equipped with a speed sensor, pressure sensors in the hydraulics, 3-axis vibration sensor, borehole length measurement and temperature sensor. The sensors are additionally attached to the drilling rig and no structural changes on the drill rig are necessary. All data are processed real-time at a server structure outside of the mine using AI algorithms to analyze which rock (ore or host rock) is being drilled and to perform predictive maintenance. Processed Data are visualized for the operator to optimize the workflow and the productivity.

Feb 1, 2025

By D. L. Crouse

The worldwide talc industry has experienced significant changes since the 1980's. Consolidation of companies and operations in Europe, Australia, and North America has altered the face of supply and distribution. Imports of Chinese and Australian crude have increased competition and product options. The number of processing operations without local mines has moved competition closer to the market area. Quality controls related to ISO certification and tighter specifications demanded by the customers have altered the way our mines and mills operate. Ceramics, coatings, and paper applications continue to consume the majority of processed talc.

Jan 1, 1997

By Karin Bäppler

Mechanized tunnelling is undoubtedly one of the most innovative disciplines in the international construction industry. Technological progress in the planning and production of most modern infrastructure is constantly striving for new records on basis of highly specialized solutions and know-how. Humans and technology have accomplished excellent achievements over the past few years in varied, difficult terrain. New length records are being set with the 64 km long Brenner Base Tunnel and the HS2 Railway system currently under construction in Europe. Cities are building ever longer and more demanding sewer tunnels. The paper highlights some of the challenges, trends and innovations of long-distance tunnelling projects.

Dec 1, 2022

By Terence P. McNulty

Gold-bearing outcrops were discovered in 1862 by Union soldiers garrisoned at Needles, CA, near the northwest corner of the future State of Arizona. Sporadic mining began several years later, but engineered shaft sinking and mill construction were not adopted at Oatman and the neighboring camp of Goldroad until about 1900. Geological interpretations in 1915 enabled major production during the next decade. In the late-1930s, USSR&M built a new mine and mill in Gold Road and the District flourished until closure by Federal Order L-208 in October 1942. For about a decade, Oatman’s mines were among the largest gold producers in the American West.

Feb 1, 2024

By Dae Young Kim, Sim Bo Kyung, Ebrahim Farrokh, Ki Chang Hyun

"TBM cutter life evaluation in abrasive granitic rocks is a very important issue, especially in pressurized face tunneling with mixshield TBM for which the planning of costly interventions becomes crucial. This paper presents an overview of methodologies for cutter life evaluation in rock. A comparative study is performed to indicate the predictability of cutter life evaluation methods based on detail data from the NS3 tunnel project in Singapore. A new model is developed based upon the cutter wear information of eight TBM tunnels from around the world. New methods are proposed to evaluate the optimum intervention interval length and the number of worn-out disc cutters for a tunnel project. Finally, two new laboratory tests in the evaluation of disc cutter abrasion, including a full-scale and a small-scale test, are introduced, and their test results are discussed. INTRODUCTION The issue of wear evaluation for hard rocks has been extensively studied in drilling and pavement industry. In this regard, several tests and evaluation methods have been proposed to estimate or evaluate the state of tool life (e.g. bit life for drilling). In the case of TBM tunneling, tool wear may depend on several factors such as mineral composition, strength, or type of cutting, but as the abrasion is usually the major mechanism for the tool wear in hard rock, the developed methods for cutter wear or cutter life evaluation are mostly based on the abrasion indices such as Cerchar Abrasivity Index (CAI). This paper attempts to review the major methodologies for disc cutter wear and life evaluation and to propose new methods to evaluate cutter life and intervention interval evaluation based on detail information of a mixshield tunnel project in Singapore as well as general information of some other projects from Iran, Italy, South Africa, and France. As the laboratory tests are crucial in the process of evaluation, two new lab tests are developed and used to inspect suitability of the new proposed model for disc cutter wear evaluation."

Jan 1, 2016

By L. B. Hales

December 3, 1972, James Wm. White presented the results of an instrumentation and process control survey which was sponsored by the Anaconda Company at the annual Tucson Subsection AIME meeting.(1) Twenty-six responses were obtained from questionnaires sent to 48 operating plants throughout the world. The survey results were discouraging in that there were more failures and problems than examples of success. The following quotes are taken from the text of the paper. "We run our mill by the seat of our pants." 'If these blue sky Ph.D.'s (in the instruments and controls area within research) had some operating experience they wouldn't make a lot of the suggestions they do."

Jan 1, 1981

By F. L. Pirkle

The mineral zircon is mined for use as specialty foundry sands, abrasives, ores of ZrO2 and zirconium metal, refractories, and zirconium chemicals. It is produced as one of several products from heavy-mineral sand deposits associated with fossil shorelines. Because of its low coefficient of thermal expansion, its high melting point, its high refractive index, and its chemical inertness, it is an attractive refractory material. Zircon varies from deposit to deposit in terms of grain size, grain shape, and chemical impurity. Thus, there is a wide range of commercial products differing in impurity levels, particle shapes, and grain sizes.

Jan 1, 1992

By Gunjan R. Bhattarai, K. Bhattarai

Applications of machine learning and robotics in the tunneling industry are still nascent. Research and development are ongoing in TBM guidance; prediction of TBM cutter wear and tunneling induced ground deformations; and robotic arms for segment installation, inspection, cleaning, and maintenance of TBM cutting tools. This paper presents a case study of geological profile reconstruction using multimodal machine learning. The results from this study can aid the development and application of multimodal AI technologies to generate data reports and geological profiles in real time, taking voice recordings, photos, or videos obtained directly from the field as inputs.

Jun 23, 2024

By A. J. Teske

Sustainable Development is a very broad initiative in the mining industry, with major components running over the entire life of the mine. It likely commences with pre-exploration permitting and continues to post-mining final closure and possible land reuse. Most major mining corporations embrace the sustainability initiative, either out of a sense of social responsibility or out of necessity in order to continue doing business. But many may view the overall initiative as an added ?cost of doing business.? In many elements of sustainability, there clearly can be added cost ? some as simple as complying with self-imposed sustainability reporting. Fortunately, one major element of sustainable development can clearly be shown to reduce costs ? energy resource management. This paper will describe how the mining industry sustainable development effort differs from other industries, but can benefit from their experience in energy resource management. The mining industry can utilize proven methods from other industries to further their energy management efforts. In addition, many of the resources developed and employed to promote better energy resource management in non-mining industrial settings will be listed.

Jan 1, 2010

By R. W. Amstutz

Abstract. The shaft was drilled on U.S. Government land in the Piceance Creek Basin and was funded by the U.S. Bureau of Mines. It was drilled to 723 meters (2 371') to provide access to rich deposits of oil shale, nahcolite and dawsonite for geotechnical test work and environmental mining research. Rotary drilling and dual string, reverse-air, jet-assist circulation methods were used. Drilling required 8 months. Site preparation, running and cementing the casing required another 4 months. A 2.44-meter (96-inch) ID steel welded casing, 5.1 cm (2 inches) thick was installed and 2 700 tonnes (63 000 sacks) of cement were slurried and pumped into the annulus.

Jan 1, 1980

By B. W. Madsen

Experimental results obtained from large scale (7 tons), long-term (500 days) leaching of low tenor copper sulfide ores were interpreted by a geometric model involving the movement of a reaction zone through the ore fragments. The postulated leaching mechanism involved mixed kinetics and included diffusion of the reacting species through the host rock and a chemical reaction at the surface of the mineral particles. Ore properties which were considered were ore particle size and shape, grade of ore, and mineral content. Excellent agreement between the mixed kinetic model and the laboratory leaching results was obtained when minus ½ inch ore particles were not included in the leach. Also, a satisfactory prediction of copper recovery from plus ½ inch ore with a different particle size distribution was made; however, it was necessary to modify the shape factor in the model. Predictions of copper recovery from an ore sample which included the minus ½ -inch fine fraction and leaching for 460 days was 56.5 percent, and the recovery from leaching was 47.0 percent. The presence of fines caused channeling and uneven solution distribution and inhibited the leaching rate.

Jan 1, 1974

By R. L. Russell

Production at Freeport Indonesia's Ertsberg open pit copper/gold mine started in 1972 at a rate of 7500 t/d. Mill throughput remained at that rate for a number of years until the discovery of the Ertsberg East (GBT) orebody. This discovery prompted three successive expansion stages from 1981 to 1988 that boosted production to 20,000 t/d. The discovery of the huge Grasberg porphyry copper deposit in 1988 launched a new era of much larger expansions. The first of these involved installation of a fourth primary mill in 1989 to bring production up to 32,000 t/d and was immediately followed by an expansion of the crushing and screening plant and the addition of a new south concentrator to bring production to 57,000 t/d in 1991. The addition of a primary ball mill and the changeout of the original Denver flotation cells in 1993 has served to optimize current production at a level of 66,000 t/d. A major expansion is now in progress. This includes construction of another new concentrator to house a SAG mill circuit and large Wemco flotation cells in an area created by the removal of 6,000,000t of glacial material. This current expansion, with a planned completion in 1995, will take production to 115,000 t/d. This paper describes the evolution of the Freeport Indonesia (FI) concentrator to-date and will then go into an in-depth discussion of the 66,000 and 115,000 t/d expansions.

Jan 1, 1994

By J. A. Mejia

The combination of high-resolution X-ray microtomography (HRXMT) image analysis and Lattice-Boltzmann Method (LBM) simulations has demonstrated the ability to describe real multiphase flow problems in fine coal filtration. The single component multiphase flow He-Chen-Zhang LBM model was used to simulate filtration with actual HRXMT images of pore network structures produced in filtration experiments. The analysis performed on coal, silica, and glass bead filter cakes showed that particle shape and wettability are two of the most important factors in the retention of moisture during filtration.

Feb 23, 2014