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By Peter A. Dawson, Rod L. Leonard, Karen S. Christensen

An investigation has been completed of the technical and economic feasibility of construction of a processing facility for gold extraction from arsenical tailings, grading nearly 12 g/t, stockpiled near Snow Lake, Manitoba, Canada. The tailings dump is comprised of arsenopyrite (45%), pyrrhotite (12%), and gangue constituents. The majority of the gold occurs as fully encapsulated particles or as a solid solution in the arsenopyrite grains. The chemical composition of the Snow Lake tailings (referred to as "ore" throughout the remainder of the text) is shown in Table 1.

Jan 1, 1990

By A. H. Reitsema, Hans E. van Dam

In CIP, CIL, and Heap Leach gold recovery operations, a sub-optimal activated carbon performance invariably causes a significant loss of revenues. In this paper it is shown, how dedicated analyses of carbon samples can be used as a guide in plant performance optimiza­tion. Firstly, a brief outline is given of the most important methods of analyses, including the specialized methods not normally used by mining operations, but provided by carbon manufacturers. Then, a number of practical cases are discussed in which carbon sample analyses provided insight which allowed significant improvements.

Jan 1, 1995

By Ian J. Corrans, Gary Johnson, John E. Angove

Activox® is a hydrometallurgical process used to oxidise sulphide concentrates. The process is based on two relatively simple, established unit operations; i.e. fine or ultra-fine milling (UFM) and pressure oxidation under mild conditions. An under-standing of, and ability to control the pulp chemistry during oxidation has resulted in the successful Activox® treatment ( on a batch scale) of a wide variety of sulphide flotation concentrates; • pyrite/arsenopyrite + gold • pyrite/chalcopyrite + gold • pyrite/chalcocite + gold • pyrite/enargite/tetrahedrite + gold Oxidation rates are rapid (1-2 hours retention time) and gold

Jan 1, 1995

By Terry McNulty

There are many potential pitfalls in the commercialization of innovative technology, and the failures often are remembered longer than the successes, thereby serving as deterrents to subsequent attempts. Given the dependence of the mineral industry's future on effective innovation, it is essential that we understand the causes of failure. Case histories are presented and the out- comes are analyzed in terms of the driving forces for innovation and the steps taken during development. Industry's current attitude toward and capacity for technological innovation are discussed, and a methodology is suggested for predicting successful innovation.

Jan 1, 1998

By Frederico J. Price

This paper describes the production of a specific iron oxide pellet that has given very good and consistent results as feedstock for HYL-Process Direct Reduction Plants. The sponge iron originated from these pellets has been used for the economic making of almost 15 million tons of low carbon steel via electric arc furnace meltshops. An overview of mining, benefication, pelletizing direct reduction and steelmaking for this case is given with emphasis on the characteristics of the self-fluxing oxide pellets. HYL Operator and management training is described.

Jan 1, 1979

By H. T. Mulryan

Talc is used as an essential ingredient in a variety of plastics applications ranging from polyester body patch compounds through polypropylene automotive, appliance and household furniture components to high performance parts made from liquid crystal engineering resins. This paper focuses on polyolefin applications, the three-tier market for talc in polypropylene, the effects of various tales in typical compounds and trends in each market segment. Emphasis is given to emerging markets, examples of which are polypropylene compounds that mimic higher cost resins, and polyethylene films. Customer requirements, for tales for these purposes are discussed.

Jan 1, 1993

By A. Geoffrion, L. J. Cousineau

In underground powerhouse excavations, the access to the horizontal sections of the penstocks is most often critical. Other factors which influence the schedule include: the sequences of excavation, the interface dates between contracts, the type of support for the overhead cranes and whether the roof in the powerhouse is a reinforced concrete arch or a suspended prefabricated material. At Outardes 3, Churchill Falls and LG-2, these factors, along with the size of the powerhouse and the local topgraphy and geology were studied to produce the optimum schedule.

Jan 1, 1983

By Henry A. Russell

During the last ten years Parsons Brinckerhoff has become a leader in the area of tunnel rehabilitation. A significant part of any tunnel rehabilitation program is the control of groundwater infiltration into the structure. This leakage over time, causes deterioration of the structures, and creates numerous operational problems for the tunnel operator. This paper will address current procedures for identification, documentation, and recommendations of repair methods for the control of groundwater infiltration in rail and highway tunnels.

Jan 1, 1993

By P. D. Tomlingson

Senior mining mangers that do not get directly involved in the quality of maintenance performance risk the profitability of their operations. Maintenance is not a stand-alone activity. It requires a production strategy that addresses the total life cycle of equipment from procurement to replacement and assures the fully cooperative, mutually supporting interaction of all mine departments. Only senior managers can assure this happens. This paper examines the strategies, policies and actions required to establish and sustain effective maintenance and the profitability that derives from it.

Jan 1, 2004

By Moudgil. B. M.

The amount of hydrophobic materials constituting the mineral froth strongly influences the froth viscosity. Higher truth viscosity, on the other hand, can retard the drainage of physically carried over, hydrophobic particles. In phosphate flotation tests, a direct correlation was observed between froth viscosity and recovery, and an inverse correlation existed between froth viscosity and grade. Phosphate flotation tests in the presence of a silica depressant indicated that higher froth viscosity is an effect rather than a cause for the presence of silica particles in the froth.

Jan 1, 1994

By Stephen Navin, Pablo Ferradas, Carlos Silvestri, Alexander Markov, Jon Kaneshiro

In the high Andes of Peru, two tunnels are being constructed totaling nine kilometers in length at an elevation of over 4,500 meters. The tunnels convey freezing and crystal-clear waters from rainfalls, streams, and lakes for the consumption of Lima. The drill and blast 3-meter wide by 4-meter high tunnels are being driven from both ends through folded and sheared volcanic tuff, andesite, agglomerate,and limestone, where groundwater inflow is high. This paper describes the design geological and groundwater inflow investigations and construction.

Jan 1, 1999

By C. G. Anderson

Over the past 15 years numerous pressure oxidation plants for pretreatment of gold ores and concentrates have been installed throughout the world. While, this technology is now established, it suffers in term of the complex engineering and operational characteristics inherent in utilization of high temperatures (i.e. up to225°C) and high pressures (i.e. > 400 PSIG). This paper outlines the application of an industrially proven pressure leaching methodology utilizing nitrogen species catalyzed pressure leaching and alkaline sulfide gold leaching. As such, it stands as an economic and engineering advancement in pressure leach treatment of gold ores and concentrates.

Jan 1, 2003

By C. Villa Diniz, A. H. Martins, Fiona M. Doyle

It is proposed that battery grade MnO2 can be produced directly from a manganese ore from Azul Mine in Brazil, by leaching with HCI to remove heavy metals selectively. We are working to find a way of selectively separating Cu, Ni, Co, Pb and Fe from the resulting acidic manganese chloride solution, to detoxify it and produce marketable chloride solution. Chelating ion exchange resins are proving more promising for this separation than solvent extraction with commercially available reagents. Results from batch and column ion exchange tests that characterize the behavior of copper, nickel, cobalt, lead and iron are reported.

Jan 1, 1999

By David B. Ashley

Risks in underground construction are often viewed as technical in nature; "running ground, " "squeezing ground" and "chimneys" are terms that appear in construction managers' nightmares, and occasionally in their underground projects. Financial consequences of these and other project risks are reviewed. Special attention is paid to sources of cost overruns. From this study a structure evolves for setting priorities for risk management actions; these actions can also be tested for impact and potential effectiveness. Finally, case study reviews of six underground projects indicate the "state of the practice" for financial risk management.

Jan 1, 1983

By Hanguang Wu, V. Izaxon, Sukumar Bandopadhyay

This paper presents an analysis of the heat transfer process between the mine ventilation air and the frozen rockmass. The heat transfer model takes into account not only by the mutual change in air and rockmass temperatures, but also by the phase change of ice-water- ice. Based on the analysis presented here it is concluded that the mine thermal regime can be regulated by having the air enter the mine through mined-out excavations or development airways.

Jan 1, 1995

By H. Benedict

For many years, asphaltic lubricants have been used on large open gears. The asphaltic's diluent is essential to thin the lubricant enough to be sprayed. Once the lubricant has been sprayed into place, the diluent evaporates, leaving the asphaltic to lubricate mating surfaces. Recently, this thinner has been changed to non-cancer causing diluents. The gain in safety corresponded to a lesser ability to evaporate. This paper explores how much diluent remains in the lubricant when it has been assumed to be flashing off. Having quantified the diluent in the lubricant, we can then estimate the effect this has on viscosity.

Jan 1, 2003

By A. E. Koski

This paper describes the implementation of specialized software in mine planning at the Cleveland-Cliffs’ managed Empire Mine on Michigan’s Marquette Iron Range. The application puts together years of mining experience on the eastern end of the Marquette Range beginning in the early 1960’s. The Empire Mine, in its thirty-fifth year of production, uses the software to model a complex and highly variable low grade magnetite orebody, capturing the economics of mining and processing to the final product. With special attention given to geostatistical methods, the software is used for all geologic modeling, ore reserve estimation, ore control, pit design and short and long range planning.

Jan 1, 1999

By Michael Brittan

For several years, Independence Mining Co. (IMC) has routinely used oxygen fluid-bed roasting to pre-oxidize refractory gold ores ahead of conventional carbon-in-leach (CIL) processing. Oxygen serves jointly as the fluidizing medium and the combustion gas. This technology has proven to be reliable, environmentally sound and cost-effective. IMC is a subsidiary of the Minorco group. The company operates the Jerritt Canyon (a joint venture with FMC Gold) and Big Springs gold mines in the Independence mountain range north of Elko, NV. Ore bodies in the range contain characteristic refractory ore. It requires pre-oxidation ahead of conventional CIL processing. This article describes the technology developed specifically to treat these difficult ores.

Jan 1, 1995

Machine breakdowns and maintenance delays are large contributors to lost production and increased operating costs in the mining industry. The US Bureau of Mines is investigating the applications of expert system technology to diagnostic and predictive maintenance for mining equipment. This will help increase mining productivity and decrease operating costs by reducing the frequency of equipment failures and repair times. The Bureau has begun this effort by applying expert system techniques to the diagnosis of hydraulic system problems on a continuous mining machine. This paper discusses the development of the hydraulic diagnostic expert system.

Jan 1, 1992

By G. Barelli, C. Giusti, W. H. Langer

Natural aggregate – sand, gravel, and crushed stone – is the number one non-energy mineral resource in the world in terms of both volume and value. A plan for the sustainable development of aggregate resources can include: 1) policies and economic incentives to encourage identification and protection of potential resources, 2)efficient quarrying and processing of aggregate, 3) efficient use of primary aggregates, 4) greater use of recycled, waste, or substitute material, 5) inclusion of costs of all environmental impacts in price of material, 6) reclamation to beneficial secondary uses, and 7)identification of objectives, targets, actions, and sustainability indicators. Quarrying can also contribute to sustainable ecosystems through natural habitat reclamation.

Jan 1, 2003