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By C. Alexander

Stillwater Mining Company is developing a second underground palladium and platinum mine approximately 21km (13 miles) west of their existing Nye operation in south central Montana. A 5650 meter (18,550-foot) tunnel is required to gain access to the ore bearing horizon (J-M Reef). Access and primary mine development can be accelerated through the use of two 4.6 meter (15-foot) diameter tunnelboring machines (TBM). One TBM was purchased new while the other was purchased used. Machine specifications, site support facilities, portal/launch chamber construction, TBM assembly, startup and operation are discussed in this paper.

Jan 1, 1999

By A. Halim, A. Martikainen, S. GYAMFI

This paper outlines a unique case of the development of strategies to reduce ventilation and heating costs in Konsuln iron ore mine in northern Sweden. The mine, located just south of Luossavaara-Kiirunavaara Aktiebolag’s Kiruna iron ore mine, was developed as a test mine from 2018-2020 for the Sustainable Underground Mining (SUM) project. Besides functioning as a test mine, Konsuln also contributes to ore production. The existing mine ventilation system was designed for the current production rate of 0.8 million tons per annum (Mtpa). There is a plan to increase this rate to between 1.8 and 2.0 Mtpa.

Dec 23, 2021

By A. Martikainen, S. GYAMFI

Luossavaara-Kiirunavaara Aktiebolag’s (LKAB) Konsuln iron ore mine, located just south of the famous Kiruna iron ore mine in Malmfälten in northern Sweden inside the Arctic Circle, was developed as a test mine between 2018 and 2020 for the Sustainable Underground Mining (SUM) project [1]. Besides functioning as a test mine, Konsuln also contributes to ore production. The existing mine ventilation system was designed for the current production rate of 0.8 Mtpa using conventional diesel machines. The design was created by Kiruna mine ventilation team, Stina Klemo and Joakim Jonasson, in cooperation with a consultant, Tomas Bolsöy from EOL Vent Mining AB. There is a plan to increase this rate to between 1.8 and 3 Mtpa in the future, and this requires the primary fans to be upgraded. Therefore, a study was carried out to determine whether using ventilation on demand (VOD) could avoid this fan upgrade and reduce Konsuln’s ventilation and heating power costs in the future. The study also investigated whether using battery electric vehicles (BEVs) along with VOD or as a standalone strategy could further reduce these power costs. In addition, the study analyzed the suitability of heating power reduction strategies presently or previously used in Nordic countries and Canada to investigate potential additional strategies to reduce heating power cost, the largest portion of Konsuln’s ventilation and heating power costs.

By Robert P. King

In April, 1975 the Colorado School of Mines began monitoring rock mass response associated with a long- wall shield demonstration project near Raton, New Mexico. This project was sponsored by the U. S. Bureau of Mines (DOE) and performed at Kaiser Steel Corporation's York Canyon Mine. Two of the results of the intensive instrumentation effort are the empirical subsidence and horizontal strain models presented herein. These models are based on data gathered during mining three adjacent longwall panels (4N, 5N and 6N). A total of 251 permanent surveying monuments were monitored over the three-panel area. Lines of monuments were oriented along panel centerlines, perpendicular to centerlines and diagonal (45O) to centerlines. Active monuments were monitored twice a week, with less frequent monitoring of stable or slow moving monuments. Primary subsidence monitoring equipment consisted of an AGA Geometer Model 75 and a Wild T-2 Theodolite with -a Wild-Sercel DI-3S distomat.

Jan 1, 1979

By P. Schilizzi

The increased impact of mining subsidence in the U.S. coalfields and the recent regulatory constraints legislated by government and state agencies have provoked an intense research effort on this topic by government agencies, coal companies and academic institutions. Subsidence and horizontal strain predictions are a basic requirement if subsidence and its associated effects are to be controlled and contained within acceptable environmental levels. As a result, several such prediction techniques have been proposed or are currently under development to assist coal operators in minimizing the detrimental effects of these surface deformations. VPI&SU has been actively involved in this research effort in the past few years, with particular emphasis on the Appalachian coalfield. During the initial stages of this research a large number of subsidence case studies were collected from the literature, the coal industry and government agencies. In total, data from 32 longwall panels and 60 room and pillar panels were collected. This data bank was used to determine relationships between the basic mining and subsidence parameters, in order to allow the evaluation of the various prediction methods for the Appalachian coal region. Based on this data two subsidence prediction techniques, one based on profile functions and the other on influence functions have been developed. Profile function methods provide a tool for a fast calculation of subsidence on a line across a mine panel. Influence function methods, on the other hand, allow for a more detailed calculation of ground movements, in any mode and at any depth, on a grid or at any specific point. The limitations of the data of the collected case studies, i.e. accuracy of surveys, frequency of monitoring, lack of horizontal movement measurements, etc, led VPI&SU to the initiation of a detailed subsidence and strain monitoring program above a number of active mines, located in three major coal producing counties of Virginia. The aim of this program was to enhance the data base with accurate and complete measurements of surface movements and to allow, therefore, the refinement of the prediction techniques. This paper presents this monitoring program, discusses in detail the results obtained from three specific case studies and provides recommendations for the implementation of the field data in the general prediction methods.

Jan 1, 1986

By D. K. Dysinger

The U.S. Bureau of Mines investigated leaching of chalcopyrite with sulfuric acid-oxygen under conditions anticipated during in situ leaching. A central composite experimental design was chosen to study oxygen pressures of 150, 300, and 450 psi, leach temperatures of 35?, 65°, and 95° C, oxygen-to-chalcopyrite mass ratios of 0.5, 1.0, and 1.5, leach times of 8, 16, and 24 hours, initial acid strengths of 0.6, 1.2, and 1.8 g H2SO4/g chalcopyrite and pyrite to chalcopyrite mass ratios of 0, 1, and 2. The leaching kinetics were consistent with the shrinking core model. A quadratic response surface model was used to determine linear and interaction effects of the design factors on rate constants from Arrhenius correlations.

Jan 1, 1993

By K. Adam

The sustainable management of solid wastes, including the wastes emanating from portable batteries, consists one of the main objectives of the current EU Environment Framework Programme. Overall reduction in the quantity and volume of disposed wastes, elimination of dangerous species within the waste streams and wastes recycling comprise specific targets of this policy. Within this framework a Greek funded research project entitled ?Development of an Integrated Alternative System for the Environmentally compatible Management of Used Batteries and Accumulators - DIASBAT?, was recently completed by a research team consisting of major Greek Battery producers and retailers, Research Organisations, Universities and Environmental Consultants. The aim of the project was the development of an Efficient Alternative Management System for spent portable Batteries and Accumulators, (B&A), in compliance with the prevailing EU and national environmental legislation, taking advantage of the state-of the art technology. The present article summarises the research carried out within the DIASBAT project in order to review and develop a set of sustainability indicators for the assessment of the effectiveness of Spent Portable Batteries Management Systems (SPBMS). Based on the European experience and practice, various indicators were initially examined regarding the performance evaluation of SPBMS. Specifically, the indicators used in European studies conducted to assess the environmental, social and economic impacts of the recently issued Batteries Directive 2006/66/EC, as well as the indicators used by European Collection and Recycling Organisations (CROs) to assess the performance of SBPMS across Europe were presented and analyzed. Additionally, the set of indicators used within DIASBAT to assess the effectiveness of alternative Spent Portable Batteries Collection Schemes developed within the project, are presented. The experimental collection networks of the DIASBAT project included schools, selected retail stores and a pilot network set up by the Greek Institute of Geology and Mineral Exploration (IGME). From the evaluation of the various indicators, it was deduced that in order to assess an Integrated Spent Portable Batteries Alternative Management System, a multi criteria analysis approach is required. Within the general principles of sustainable development, there is a need for different qualitative and quantitative indicators to be combined, taking into consideration critical parameters such as: annual portable batteries collection rates, compliance with the targets set up by the prevailing European and national legislation, economic performance of the System - and finally social criteria - environmental sensitization according to age, gender, economic prosperity, educational level etc.

Jan 1, 2007

By J. B. Pateiro Fernandez, S. Möllerherm, E. Drüppel

"Since 1997 the Institute of Mining Engineering 1 at the Aachen University is dealing with the concept of sustainable development in the mineral industries. During this time it has conducted several research projects in this field. Its latest project is on the development of sustainability indicators for the German mineral industry. This paper describes some results of this project. A process chain analyses have been carried out identifying economic, social and environmental effects of the minerals extraction. Thirty indicators reflecting the particular conditions in the mineral industry have been designed. One important challenge was the design of quantifiable indicators taking into account the life cycle of a mining operation as well as mineral beneficiation and enrichment of the raw material."

Jan 1, 2005

By N. P. Titkov

This paper presents the results of laboratory and pilot plant investigations for the development of efficient methods of beneficiating hematite ores from the Krivoi Rog, Kursk Magnetic Anomoly, Olenogorsk, and other localities. The tests included gravity, magnetic (in a high intensity field), flota¬tion, and magnetizing roasting methods. It was possible to develop efficient beneficiation methods depending on the mineral composition of the ore and degree of dissemination of ore and gangue minerals. The paper shows the relationship between the iron silicate and quartz content of the ore and the technologic indices of the various beneficiation methods. Some of the conclusions based on these investigations and the technical and economic computations related to the cost of one ton of pig iron produced from concentrates obtained by the various beneficiation methods are: 1. If the hematite ore is not disseminated uniformly, it is expedient to use a combined gravity and flotation process. Ore particles up to 50 am. in size are beneficiated by gravity (heavy suspension, jigging, and others) and yield a lump concentrate. The middlings from this process are recrushed and floated; 2. Finely disseminated hematite ores, containing small quantities (less than 5 percent) of iron silicates, are most effectively beneficiated by flotation. Anionic (sulphate soap, tall oil emulsion with various foam depressors) as well as cationic collectors may be used. Depending on the mineral and chemical composition of the ore, it is possible to obtain concentrates containing up to 65 percent iron with an extraction up to 94 percent; 3. Finely disseminated, mixed hematite-magnetite ores may be beneficiated by flotation or a magnetic separation-flotation process; 4. Finely disseminated hematite ores, containing large quantities of iron silicates and earthy hematite ores are most efficiently beneficiated by the magnetizing roasting method. This method will yield concentrates containing up to 68 percent iron with extractions up to 90 percent. Although beneficiation by the magnetizing roasting process is costly, it will nonetheless, when employed on this type of ore, yield the least expensive pig iron.

Jan 1, 1960

By Homer S. Anderson

To clarify what r mean about this long title, I would like to define the term technology. A standard definition of the word "technology" is "a technical method of achieving a practical purpose". Incidently, another definition of the term is merely "technical language". The same dictionary defines the word "technology" as "having a special, usually practical, knowledge of mechanical or scientific subject." Naturally, the practical purpose of the subject with which we are concerned is solving of problems we encounter in the mining industry. I might further describe the subject of this discourse by defining the term "manager". An old definition, "one who dispenses the duties of his position with care and economy." In line with the above definition most of the technology with which we in the mining industry are confronted with deals with some form of cost reduction. This may be related to the speed of doing an operation or to saving of labor or supply costs. These can be improvements of an existing method or the result of new processes or inventions, such as new machinery.

Jan 1, 1974

By K. B. C. Brady, B. E. Scheetz, J. E. Cuddeback, T. W. Bergstresser, W. A. Telliard, S. C. Parsons, R. J. Hornberger

Two weathering procedures are being developed by the Acid Drainage Technology Initiative in cooperation with federal agencies(OSM and EPA). Objects are to: (1) standardize existing humidity cell and leaching column procedures; (2) improve test methods by maintaining a carbon dioxide enriched environment needed to optimize carbonate mineral dissolution, and quantifying particle size variables to evaluate reaction kinetics, and (3) provide flexibility in test method implementation consistent with EPA guidelines for Performance-Based Measurement Systems. Preliminary results indicate the CO2enriched leaching environments produce alkalinities that are similar to field observations and greater than the tests run under atmospheric PCO2. Leaching columns produce higher alkalinity than humidity cells.

Jan 1, 2003

By Y. Ye, J. D. Miller, E. Pacquet, S. Gopalakrishnan

From laboratory research activities during the past five years, it is now evident that effective flotation separations can be achieved with the high-capacity air-sparged hydrocyclone. The effectiveness of the equipment has been demonstrated on a pilot-scale basis (1 tph) for a number of mineral commodities including coal, copper, gold, and industrial minerals using a nominal 5-cm x 50-cm system with separation efficiencies equivalent to those achieved by conventional flotation machines. The high specific capacity of the air-sparged hydrocyclone (100 to 600 tpd per cubic foot of cell volume for a nominal 5 cm x 50 cm system compared to 1 to 2 tpd per cubic foot of cell volume for conventional columns and mechanical machines) makes it especially well-suited for the pro- cessing of low-grade ore. As a result of these pilot-scale successes, a number of plant-scale test programs are planned for larger-diameter units to establish wear characteristics and scale-up relationships for design purposes. The status of the air-sparged hydrocyclone technology is reviewed in the present paper, including a description of the system, fundamental considerations of flotation mechanisms, general discussion regarding the effect of control variables, and the significance of feed characteristics.

Jan 1, 1988

By W. Baguley, L. P. H. Greenhalgh, R. P. Riley

The traditional impeller system for aeration and suspension of slurries, e.g. in bacterial oxidation plants, is the vertical flat blade turbine (VFBT) . This type of impeller is energy-intensive, which results in a heavy-duty design of shaft, gearbox and drive. The Mixtec BX04 agitator development programme is designed to evaluate the use of the new generation of hydrofoil impellers which consume less power and thus have potential for capital and operating cost savings as well as being possibly less damaging to the bacteria. The early tests on pyrite oxidation in a 300 litre laboratory pilot tank using the Thiobacillus ferro oxidans bacteria, showed that hydrofoil impellers had superior characteristics to the VFBT impeller and to air-agitated pachucas, with lower energy input. The geometry of the air sparge ring was found to be very important in optimizing the system. These early successes resulted in a prototype impeller and sparge ring beinq tested in a 9m3 tank where oxygen uptake in water, impeller cavitation at different impeller speeds and air flows were evaluated. Resulting from this work was the supply of an agitator unit to an operating bacterial oxidation plant where it has been successfully evaluated. This paper describes the development work so far carried out

Jan 1, 1992

By A. M. Stone

Following the conceptual idea of a Continuous Elution Process early in 1982, the system was successfully pilot plant tested at Western Mining's Kambalda gold plant in December 1982. As a consequence of these tests the Ok Tedi elution ciruit design was changed from batch operation to continuous operation resulting in a reduction in the number of similarly sized elution columns from five operating with one standby to one operating with one standby and halving the process steam requirements. In addition to providing significant capital and operating cost savings the continuous process was simpler to operate than the batch process.

Jan 1, 1989

By Kenneth P. Neumann

The development of the Cyprus Thompson Creek Molybdenum Deposit near Challis, Idaho, began in 1967 when the first mining claims were staked on the intrusive rock outcrop. Exploration drilling continued for the next 14 years. During 1978, a decision was made to develop the deposit. In December, 1980, approval of the Environmental Impact Statement was received and construction of facilities and waste rock removal began. By the middle of 1983, 126 M metric tons of rock had been removed and all facilities were completed. The high work ethic of Cyprus Thompson Creek employees combined with innovation has made the mine one of the most efficient in the United States today.

Jan 1, 1983

By Chris Bennett, Drupad Desai, Kirit Mevawala

INTRODUCTION The design/build (D/B) philosophy of contract delivery is neither new nor unusual when it comes to at-grade, elevated or high-rise structures. But when it comes to constructing underground facilities, there were no examples to be followed in early 90sin the continental United States or its territories. When DMJM+HARRIS was selected as general architectural and engineering consultant for the Tren Urbano (TU) project in Puerto Rico, one of the requirements of the Federal Transit Administration (FTA) for funding commitment was to use TU as a demonstration project utilizing design/build contract delivery method. Now fifteen years later, New York City Transit (NYCT) has instituted a similar requirement for their first Tunnel Boring Machine (TBM) contract for the Second Avenue Subway. As with most construction mega-projects, lots of things have happened and there were several lessons learned from the TU experience that are now being applied to Second Avenue. Both of these projects require building tunnels and underground transit facilities in heavily traveled corridors of an urban city, in the vicinity of active business and commercial enterprises. To enhance the challenge, there are noise and vibration sensitive and historic urban receptors either over or along both the transit corridors. Column free Tren Urbano station caverns over18 m (60 ft.) wide were built in soft ground conditions within 3.6 m (12 ft.) of the surface under an aging heavy utility corridor, while NYCT tunnels with station structures stretching the limits of rock caverns to 34.8 m (100 ft.), were planned in rocky geology with the presence of shear and fault zones and some mixed face conditions. BACKGROUND During the early period of design/build experimentation, the speed with which the contract procurement packages could be put together enabled the owners to take advantage of the major efforts underway to rebuild the infrastructure that was suffering from post-World War II neglect. Use of design/build for new starts was unheard of and most of the projects were smaller in nature in order to allow the methodology to be tested. Development of functional design packages with the understanding that the D/B

Jan 1, 2005

By Ian Kilgour

The development of the Escondida concentrator is described, from the design of the original 35,000 tpd concentrator through successive expansions and modifications to the 115,000 tpd plant currently under construction. Operating problems, and the steps taken to overcome them, are briefly discussed. Reasons for key equipment choices and flowsheets modifications in the expansions are explained, with some emphasis on the flotation circuit.

Jan 1, 1995

By S. McAlister

This paper outlines the development of the Falcon enhanced gravity separator. Design objectives included continuous operation with sharp separations, mechanical simplicity, minimization of process water demand, the ability to apply a centrifugal field up to 300G's, unit capacity in excess of 100 t/h within a footprint of 10 square meters, a capital cost below $US 4,000 per t/h capacity, and total operating costs of less than $US 0.40 per tonne. A parallel development has been inexpensive, effective, semi-continuous equipment for recovery of precious metals in the free metallic state. These objectives have been largely met. There are significant opportunities for the technology in many mineral processing applications.

Jan 1, 1998

By R. A. Bergman, P. G. Thornhill

Development of the Falconbridge Ferronickel Process for treatment of lateritic nickel ores began with laboratory work in 1955, the year the Company commenced exploration of its concession in the Dominican Republic. Process development centred on selective reduction originally directed to producing calcines amenable to ammonia leaching, but later found suited to electric smelting. The reduction step of the process was developed in a 25 tpd shaft furnace pilot plant located in the Dominican Republic, to which was later added an electric melting furnace. After almost 3 years of development work on this scale the plant was expanded to 100 tpd for fixing design data for a commercial plant. This took the form of the 30,000 ton per year Nickel Ferro-nickel Complex of Falconbridge Dominicans, which started up in 1971.

Jan 1, 1979

By J. A. Lepinski

The FASTMETSM Process is a coal-based process for converting iron oxide fines into metallic iron. The end product, direct reduced iron (DRI) is used as a low residual charge material in electric arc furnace steelmaking. This paper describes the FASTMET Process and its potential application in the United States. Operating results from a 175 kg/h process simulator are presented. Characteristics of the end product are discussed. Process economics are reviewed along with plans for scaling-up the process to full commercial size.

Jan 1, 1993