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By Robert C. Bacon

The first commercial installation of the Dashaveyor has recently been completed at the White Pine Mine in Northern Michigan. After four years of development work, including prototype testing, and pilot plant operation, this new and unique system is being tested under operational conditions. Many of you may be familiar with the concept through numerous articles which have appeared in the technical press. But this discussion of the system will be simplified and less time consuming with the presentation of a portion of a film showing the Dashaveyor in actual operation. After the movie, I will show some slides which will supplement and clarify it and hopefully lay the basis for questions you will undoubtedly wish to ask.

Jan 1, 1968

By Bruce Kennedy, Dan Nilsson

Mining means drilling and blasting in order to break down the rock, loading and transport, and often also crushing the ore down to a suitable size. These operations can be done in open pits or in underground mines, and also, to a lesser extent, in marine mining. The same operations are also used in various types of construction, i.e., for roads, water power stations, etc. Before beginning a detailed economic analysis of the factors which enter into deciding whether to mine by open-pit or underground mining, and at what point a change should be made from open-pit to underground mining, or vice versa, it is of interest to consider some general factors.

Jan 1, 1982

By S. Zamna, M. E. Defoe, Franklin T. Davis, Earl Rau, Yarroll. Warren H., Paul D. Chamberlin

This section contains a description of the ore processing methods of the walled industrial minerals that are not described in major sections of the book. Table I contains the production figures for each of these commodities in the United States and the world. Specifications for concentrates or final mineral product are also summarized as well as prim for them at the time the section was written. In each chapter an attempt has been made to provide the reader with information on the common commercial mineral or minerals involved with the commodity, some of the uses. the processes used to recover and concentrate the minerals, as well as geographical areas where these process are utilized.

Jan 1, 1985

By Barry K. Johnston, Norman W. Bainbridge, Neville C. Lockhart

CSIRO and its collaborators have developed a major R & D project on dewatering of coal. This involves sub-projects on (i) the fundamentals of coal-water associations; (ii) reducing the variability of product moisture levels from small coal centrifuges; (iii) process mechanisms and optimisation for fine coal dewatering; (iv) pilot scale testing, engineering development and innovation. Results from each of these sub-projects are presented, and the pilot facility incorporating a vacuum filter, belt press, membrane press, hyperbaric filters and centrifuges, is discussed. The vacuum filter and membrane press can be configured for electric-field assisted dewatering, which provides substantial enhancements in the rate and degree of dewatering for fine coal, coal tailings, and other suspensions.

Jan 1, 1995

By I. Dumitrescu

Since 1990, the entire Romanian mining industry has suffered a major restructuring, i.e. technical and economic. The large majority of the remaining active mines are these with a chance for economic comeback. This is also the case for the mines that belong to MINVEST Deva Company; most of the mines are closed, and are waiting to be reclaimed. The authors present the closing procedures of the former copper mining perimeters managed by MINVEST. It is well known that pollutants of concern for the environment must be monitored to obtain reliable information on the quality of ambient conditions and to minimize their impact on the environment. Consequently, the monitoring problems during the closing procedures will be presented.

Jan 1, 2008

By P. Holman

I would like to start this paper by looking back about twenty years to see where we have been in the mining industry. We will also look forward a bit and talk about what lies ahead. Here is what has happened to the world economy since the 1970s. Economic growth was strong in the early 70s, but slipped into a recession in the middle of the decade. Then, after a fairly decent recovery recession struck again in the early 80s and since then growth has been rather sporadic. All in all, it has been a real roller coaster ride. There will continue to be plenty of ups and downs in the world economy in the future.

Jan 1, 1993

By Warren D. Stanford

The Alligator Ridge mine is a near-surface gold mine located in a remote area 113 km (70 miles) northwest of Ely, NV. The deposit was discovered in 1976 by a lone prospector working under a grubstake contract for Amselco Minerals Inc. Evaluation of mine potential proceeded quickly. Favorable drilling results led to feasibility and mine design studies by the end of 1978. Mine construction began in early 1980. By September of that year, the process plant was fully operational. The first gold was poured a few months later. Alligator Ridge is designed to produce 1.9 t (60,000 oz) of gold each year. The projected mine life, based on proven reserves, is to mid-1988. However, Amselco is actively conducting exploration nearby for additional reserves to extend the mine's life. Amselco, a subsidiary of the British Petroleum Co., is based in Denver, CO. The company is mine operator and jointly owns the project with Nerco Minerals Inc., a wholly-owned subsidiary of Pacific Power and Light. Alligator Ridge is Amselco's first US mining operation. Geology Alligator Ridge, so named because it appears in outline to be an alligator at rest, contains disseminated micron gold embedded in iron-streaked siltstones. Although definitive conclusions have not been drawn on age and origin, the gold ore bodies are probably young by geological standards. They were formed in a recent volcanic period still evidenced in parts of Nevada by geysers and hot springs. As these superheated solutions rose through the permeable siltstones, they deposited minerals in the rock and formed the present gold ore bodies. During 1977, an extensive soil geochemical sampling program with additional geologic mapping and outcrop sampling were conducted. The results generated several drill targets. Initial drilling was performed in November and December 1977, and ore grade mineralization was encountered in the first drill hole. The Alligator Ridge mine is unusual in relation to other and more recent western US mineral discoveries in that it occupies an area that had no previous mining history. The ore deposits are hosted in upper Paleozoic sedimentary rocks that consist predominantly of a thick carbonate sequence. The main ore host is the Devonian-Mississippian Pilot shale, which occurs locally as a sequence of thin bedded calcareous, carbonaceous siltstones and claystones. The maximum observed thickness of the Pilot section in the mine area is about 140 m (460 ft). Rocks in the Alligator Ridge area have been folded into a series of low amplitude anticlines and synclines that strike north-south and plunge to the south at about 20°, with limbs that dip nearly 20°. The folds have been truncated and deformed by later high-angle faults that generally strike northwest. Although multiple stages of movement are evident on the fault systems, the youngest period of activity is along the major northeast trend. The predominant structural pattern in the area is of the basin- and range-type high angle normal faults. Alligator Ridge is actually a horst block between two basin and range faults. Vantage Ore Deposits There are three principal ore deposits within the Vantage Basin and several smaller satellite mineralized areas. The three Vantage deposits are encompassed in a mineralized zone that covers an area 915 m (3,000 ft) long and 305 m (1,000 ft) wide. All mineralized zones have been outlined by more than 600 rotary drill holes, with an average depth of 150 m (500 ft). Mineralization occurs in both carbonaceous and oxidized rocks. The carbonaceous gold-bearing material is not amenable to current heap leaching practice. Therefore, only oxidized ores are now treated. The carbonaceous gold-bearing material is segregated and stockpiled as it is encountered during mining. The three ore bodies occur along a north-northeast strike, with mineralization becoming progressively deeper from north to south. The ore block dimen-

Jan 6, 1984

By Lars Olaf Höglund

MiMi has been set up to be i) visionary, ii) strategic and iii) long-term. The planning as well as the executive phases involves industry, academia and authorities in close co-operation. MiMi focuses on improved, economically efficient management of mining waste, a challenge that requires combined and integrated research efforts across discipline boundaries. The MiMi programme is financed by the Swedish Foundation for Strategic Environmental Research (MISTRA) with support from the mining industry. The first programme phase covers the period 1997 - 2000, with intentions for additional phases. Planning, experience and results from the first programme period are highlighted. INTRODUCTION Most of the mining activities in Sweden takes place in the No

Jan 1, 2000

Changes have been made in the Bulletin, Section I., for this month ; Personal and Employment columns have been added, and a Forum, in which will be included letters and discussions of general interest to members of the Institute ; live news and new matter have been inserted near the front; lists of officers and committees are placed next to the technical section, while standing matter and other information which is interesting chiefly when sought for, has been segregated as much as possible. Members are urged to co-operate with the Editor by sending in news items of themselves and others, and by giving some of their spare time to this department each month.

Jan 4, 1913

"Australia’s largest rail freight network operator, the Australian Rail Track Corporation (ARTC), has selected GE Transportation’s Movement Planner solution as the key technology enabler for its Hunter Valley-focused network control optimization program.ARTC’s Newcastle-based network control, is the nerve center of Hunter Valley rail operations, where locally based train control professionals make thousands of decisions every day to safely support the annual movement of more than 24 kt/h (26,400 stph) of freight, and tens of thousands of coal, freight, grain and passenger trains each year.ARTC plans to transform its train control function by integrating and then building on Movement Planner, an advanced software solution by GE Transportation that provides real-time rail traffic planning and optimization to enable freight to move more efficiently. “The Hunter Valley rail network is one of the busiest and most complex in the country, supporting the largest coal export port in the world,” ARTC managing director and chief executive officer John Fullerton said.“As bulk freight demands grow, rail operators like ARTC and supply chains like the Hunter Valley coal network need to be creative in the way they respond so the Australian economy doesn’t miss out. That’s why we have conducted a worldwide search to find globally proven solutions that will improve our network productivity and efficiency,” Fullerton said.The Movement Planner solution considers multiple factors including train schedules, trafficcontrol systems and train movements relative to each other and then develops an optimized traffic plan for the trains throughout the network. Existing GE customers have benefited from increased visibility of network operations, higher velocity, less dwell times, and improved on-time performance across their networks."

Jan 1, 2018

By Mark Van Dyke, Ted Klemetti, Jake Beale, Zoheir Khademian, Joe Wickline

In 2016, a 3.7-ML magnitude event caused by mining activity occurred at a longwall mine in southwestern Virginia which was recorded by the United States Geological Survey (USGS) and felt by local residents. The event was the largest of its kind since a global mine design change by the operator was instituted in 2008 following three large events in 2005, 2006, and 2007 (3.4, 4.3, and 3.4 Moment Magnitude (Mw), respectively). Two of the three pre-2008 events (2005 and 2007) damaged ventilation controls in the mine which fueled a mine fire. In 2016, the mine’s management requested researchers from the National Institute for Occupational Safety and Health (NIOSH) to access geological data and determine what parameters could possibly lead to events of a magnitude of 1.0 ML or greater. Evaluation of 2152 geological data points and modeling revealed three major geological factors in common with the majority of the 181 recorded +1.0 ML events from 2009 through 2016. Three levels of seismic potential were identified as follows:

Aug 4, 2023

By Eric Forssberg, Ming-wei Gao

Four parameters of the Drais stirred ball mitt, i.e., bead load, bead size, flow rate and top feed size have been studied regarding their influence on the specific surface area. A factorially designed scheme was employed for conducting 27 mitting tests. The results show that the bead toad is the most important parameter in terms of increasing the specific surface area with less energy consumption. The bead size is also important. The optimum ratio of bead size to top feed size is found to be 14 to 80, which is much wider than in bat2 milling. The variations in flow rate and top feed size appear to influence the process insignificantly.

Jan 1, 1992

Teeter-bed (i.e., hindered-bed) separators are used throughout the mineral processing industry for both classification and density separation. The high capacity and sizing characteristics of these units make them ideal for feed preparation prior to coarse flotation (+0.100 mm) circuits. Teeter-bed separators are typically easy to control with two basic operating parameters including fluidization water rate and bed level. However, data show that these two parameters greatly interact with one another. Given this finding, a high-level automatic control scheme was developed and implemented on a full-scale separator. In addition, dialogue with plant operators has led to several simple changes to an already established design that improves operational and maintenance characteristics.

Jan 1, 2010

By Ch. Arvanitidis

This paper presents the design solution for an actual case of settlement tanks, for a wastewater treatment plant under construction, actually founded on swelling clay (the nature of which had not been appreciated beforehand) and suffering considerable damage as a result. Two points of interest prompted the use of a numerical model as an alternative approach to the traditional method of analysis: First, the desire to compare the in situ measured deformation and displacement of the tanks with the figures calculated by the numerical model. Second the need to check the validity of the suggested solution as a remedy, i.e. the replacement of a certain thickness of clay by graded material.

Jan 1, 2005

By Mary-Lee Athorn, David A. Barratt

An opportunity to compare the performance of different tunnel boring machines (TBMs) operating in similar rock conditions occurred during the construction of a major water scheme in the UK. The principal objectives of this study were: (i) To collate, analyse and present the data available for the four TBM drives of the Kielder Aquaduct Scheme in terms of the tunnelling system performance and the downtime experienced, particularly where these were influenced or controlled by geotechnical parameters. (ii) To isolate the major sources of machine downtime and highlight those aspects of the tunnelling system that critically affect tunnelling progress rates (iii) To determine, by statistical techniques, relations between TBM performance and rock properties.

Jan 1, 1986

By P. Pages, J. Lombard, F. Fagnant, G. Bresson

This study is devoted to the improvement of the decision-making process in occupational protection of uranium miners in France. Its purpose is to apply the principles which are recommended by the I.C.R.P. in the field of radiation hazards. These principles, which have introduced the notion of "optimization" in standard setting, suggest the importance of applying cost-benefit and cost-effectiveness analysis to this sector. The objectives here are twofold : to evaluate the present organization of radiation protection on the basis of a simulation model of polluted air flow in the mine (due to the decay of a radioactive gas, radon) and to develop cost-effectiveness analysis of the various radiation protection policies.

Jan 1, 1981

By J.N. Kohmuench

Teeter-bed (i.e., hindered-bed) separators are used throughout the mineral processing industry for both classification and density separation. The high capacity and sizing characteristics of these units make them ideal for feed preparation prior to coarse flotation (+0.100 mm) circuits. Teeter-bed separators are typically easy to control with two basic operating parameters, including fluidization water rate and bed level. However, data show that these two parameters greatly interact with one another. Given this finding, a high-level automatic control scheme was developed and implemented on a full-scale separator. In addition, dialogue with plant operators has led to several simple changes to an already established design that improves operational and maintenance characteristics.

Jan 1, 2010

By William Gleason

"Technology of all forms has experienced exponential growth in recent years, and there is no sign of it slowing down. This growth has presented amazing opportunity and significant challenges in nearly every aspect of daily life. Some of these changes are seen and experienced every day as we turn to our smart phones, tablets and smart watches to help with us with everything from directions to the store to managing our health. And other technological growth takes place far away from the public view but can have as much of an impact on our daily life as does shopping at Amazon or connecting with friends on social media.At the “THRIVE 2018, Innovations Advancing Mining” conference presented by SME on Sept. 27 at the Sheraton Pittsburgh Hotel at Station Square in Pittsburgh, PA, the focus was on innovation and how it affects the global mining industry.More than 100 people were on hand for the inaugural event, and they were treated to a unique program that focused on the cutting-edge innovations that will carry the mining industry into the future while increasing safety and productivity along the way.2018 SME President Barbara Arnold was the driving force behind the conference and put together the technical program with a focus on innovation through the entire mining life cycle and into the future. Talks ranged from more efficient and safer ways to extract minerals to some of the most advanced end uses of minerals and metals, including the use of 3D printing to create precision parts for machines and humans from advanced metal alloys.“We need to adapt new technologies to our industry and develop additional technologies as we provide materials and metals for infrastructure and energy development in the United States, around the globe, and to the Moon and beyond,” Arnold told Mining Engineering. “Our inaugural THRIVE conference sets the stage for these innovations to be applied and to continue to be developed. Our mining industry can only continue to thrive with these advances.”"

Jan 11, 2018

By S. Kmet, A. Nguyen-Van, H. J. Schulze

The P/B collision and attachment interactions in fine particle flotation have been quantitatively analyzed. New models for attachment probability and kinetics of ‘true flotation’ have been developed. The results are given for both a single bubble and a bubble swarm. The mechanism of the attachment event is also examined. It is shown that (i) impact collision mechanism and rolling mechanism can be ignored in actual fine particle flotation and sliding mechanism is of importance for attachment of particle onto the bubble surface (ii) the attachment probability of fine particles is independent of bubble size and determined by the kinetic measure induction time of hydrophobicity. The theoretical predictions are also compared with the experimental data.

Jan 1, 1995

By B. K. Gupta

Arch Mineral's Captain Mine has used the Bucket Wheel Excavator System(BWE) for over 3 years in conjunction with a 180 yd3 (138M3) stripping shovel. The bucket wheels prestrip the soft overburden ahead of the shovel. This soft overburden is brought to the spoil side through a series of shiftable conveyors and placed by a spreader over the ungraded or partially graded shovel spoils. The placement of the soft overburden and top soil is accomplished in a manner that meets the reclamation mandates. The prestripping by the BWE has reduced the incidence of the highwall and spoil slides, depth the stripping shovel has to dig and the volume handled by the pullback draglines.

Jan 1, 1984