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By Grant J. Goddard

"The Iron Ore Company of Canada (IOC) has been in operation for over 30 years. Today, and in the future, technology and its application will play an ever more critical role in the company’s business success.The Carol Mining and Concentrating (CMC) division of IOC is energetically applying technology today to enhance performance and results, and is aggressively exploring opportunities to apply technology to support improved business results in the future.A critical area of focus is the application of technology to maintenance management performance. CMC has taken a “back to basics” approach to the fundamentals of maintenance management in 1995 and 1996. In parallel, the mine is aggressively implementing its Vision 2000 maintenance integration plan. This plan is targeted at levering the energies applied to sound maintenance management fundamentals as the company moves to a fully condition based maintenance approach.This paper discusses some of the strategies, key technologies and objectives of theVision 2000 maintenance integration plan at the mining operations of IOC."

Jan 1, 1996

By Charles L. Kimbell

The year 1979 was a period of increased activity for the world's mineral industry, distinctly in contrast with 1978 when estimated world crude mineral output value declined slightly and most phases of the industry's activity were somewhat curtailed. In 1979, most major mineral commodities recorded significant gains in output, with a substantial number achieving new record highs; details on trade levels for 1979 were not available, but increases over those of 1978 were expected on the basis of partial data. Consumption of most commodities edged higher; in some cases the higher demand levels were met largely through draw-downs of stocks accumulated in recent years, while in other cases notable output increases were required to meet demand. Actually, 1978 was not a bad year for all elements of the mineral industry if changes in output levels of the various commodities are considered as a measure of performance. There were far more individual commodities registering production increases between 1977 and 1978 than registered declines, but some of those reported as declining were relatively major commodities (bauxite, aluminum, copper and zinc were notable), Moreover, the upturn in productive activity in 1978 was not matched by increases in profits. However, 1979 was unquestionably a year of renewed expansion efforts, although some commodity areas, most notably the steel industry component, were still experiencing difficulties.

Jan 1, 1981

By Edward W. Parker

THE agreement of September, 1922, between the anthracite operators and the United Mine Workers of America, which followed the 54.5 months strike during the summer of that year, contained the following provision : The parties unite in a recommendation to Congress that legislation be forthwith enacted creating a separate anthracite coal commission with authority to investigate and report promptly on every phase of the industry and the parties hereby ask the President to request the enactment by Congress of the recommended legislation. The continuance of production after Aug. 31, 1923, shall be upon such terms as the parties may agree-upon in the light of the report of the Commission.

Jan 1, 1924

By M. T. Ansari

"This article explains the ways in which investment on mining infrastructure is a geopolitical issue. It discusses the effect of installing sufficient infra structure to get the product to the world market, and argues that there is a risk involved in depending on traditional suppliers who wish to invest in the infrastructure. It explains how to make a distinction between dedicated purpose infrastructure and general use infrastructure by examining the positions of the main actors in mining projects. It argues that these positions can not be understood as analogous to projects in developed countries. To conclude, infrastructure is a crucial link in the supply chain to market but the relative size of such projects in relation to the economy means that investors decisions in developing countries have quite different implications from those in developed countries."

Jan 1, 2011

By B. E. Warren

Jan 1, 1965

By P. Zhang

Previous studies have shown that separation of clay minerals from non-clay minerals is the key to economic recovery of the phosphate from the waste phosphatic clays (slime) which represent about 20- 300/0 of the phosphate mined. Small hydrocyclones of different sizes (4" and 6") were tested for sizing the slime at +10 microns in order to remove most of the clay minerals. The effect of design variables and operating parameters were evaluated. Multi-stage cycloning and the effect of dispersant were also investigated. Chemical and mineralogical analyses of different size fractions of both the underflow and overflow samples indicated satisfactorily separation efficiency.

Jan 1, 1998

By Herbert Tomlinson

The United States Bureau of Mines has engaged in a study of the conditions under which coal mine accidents, resulting in the loss of life, limb, or time to the injured person, occur from falls of roof and coal. This publication is devoted to the results of a study conducted in the coal mines of the Book Cliffs and Wasatch Plateau coal fields of Utah. To show the necessity of this study, a statement of the fatalities that have occurred during the period 1928-1930, inclusive, in the bituminous mines of the United States and of Utah, is presented (Table 1), followed by a brief description of this Utah district, its coal beds and immediate roof, thickness of cover, dip of coal beds, methods of mining, supervision, roof testing and timbering for roof support, all of which are factors in any plan devised for preventing accidents from falls of roof and coal.

Jan 1, 1932

By Herbert Tomlinson

The United States Bureau of Mines has engaged in a study of the conditions under which coal mine accidents, resulting in the loss of life, limb, or time to the injured person, occur from falls of roof and coal. This publication is devoted to the results of a study conducted in the coal mines of the Book Cliffs and Wasatch Plateau coal fields of Utah. To show the necessity of this study, a statement of the fatalities that have occurred during the period 1928-1930, inclusive, in the bituminous mines of the United States and of Utah, is presented (Table 1), followed by a brief description of this Utah district, its coal beds and immediate roof, thickness of cover, dip of coal beds, methods of mining, supervision, roof testing and timbering for roof support, all of which are factors in any plan devised for preventing accidents from falls of roof and coal.

Jan 1, 1932

By R. G. Knickerbocker, T. E. Evans, D. R. Torgeson

"INTRODUCTION Sponge iron is a product resulting from the reduction of an iron oxide at such a low temperature that fusion does not occur, and the reduced particles retain substantially the same shape as the original ore. The removal of oxygen in the reduction process leaves the metal porous and reactive. Sponge iron may be compared in general to a chemically precipitated substance insofar as reactive properties are concerned. The high specific surface and the orientation of metallic structure are factors which probably contribute to the reactive properties of sponge iron.The term ""gaseous reduction,"" as applied to iron ores, required clarification. Strong evidence exists, for example, that ore is partly reduced to sponge iron by carbon monoxide in the blast furnace at temperatures around 800° C. at a point that may be as high as 30 feet above the tuyores. In 1923 and 1924, Sims and Wood attempted to reduce iron oxide with carbon in an Arsem vacuum furnace at 980° C. These investigators found that only 6 percent of the iron was reduced to metal when the iron oxide-carbon mixture was heated for 1 hour under evacuated conditions, whereas at atmospheric pressure 70 percent of the iron was metallized. Their results indicate that the process of iron-ore reduction at temperatures below the melting point of the ore may proceed largely, if not entirely, by the action of reducing gases even when the reducing agent is solid carbon. Therefore, the term ""gaseous reduction,"" as used heroin, is defined as a process in which iron ore is brought into intimate contact with a reducing gas produced in separate-equipment from the reduction chamber itself.A large amount of pilot-plant development on gaseous reduction of iron ores has been carried out by the Bureau of Mines at the Boulder Experiment Station and had as its objective the reduction of fine iron ore by means of producer gas. The use of use gas was prompted by two considerations: First, the possible utilization of large reserves of Western noncoking bituminous coals and lignites contiguous to iron-ore drewwing; and second, an investigation of the results that might be achieved in the pilot-plant gaseous reduction of fine iron ores by means of a relatively reducing gas. The results obtained, it was felt, would be of considerable value in indicating the direction which gaseous reduction experimentation must take for the development of a commercially practicable and economic process for the production of sponge iron."

Dec 1, 1946

By J. J. Gusek

Several final pits in the Seneca No. 1 Surface Coal Mine were abandoned in the 1960's without being reclaimed. In addition, a progressive landslide aggravated by the abandoned mine land conditions was threatening a county road and private property. An AML-funded project to stabilize the landslide and reclaim the final pits was completed in 1986 for the Colorado Division of Mines and Geology (formerly Colorado Mine Land Reclamation Division). The site was visited after ten growing seasons. The land is stable and the vegetation re-establishment is strong. Volunteer native plant species are now invading the reclaimed sites.

Jan 1, 1997

By D. Grobbelaar, A. Cichowicz, D. J. Birch

The Q-coda method for estimating the quality factor Q(f)= Qo(f)n was used to characterize seismic wave attenuation in a region of the Kaapvaal Craton that includes the mining areas of the Bushveld Complex and Witwatersrand Basin. Seismic waveform data, collected by locally distant stations of the South African National Seismograph Network (SANSN), consisted of mining-related events with magnitudes ranging from ML 1.8 to ML 4. Q was calculated for nine different source-receiver pairs spanning the study region. A weighted average Q based on the number of available data gave an estimated attenuation relation for the study region of Q(f) = 327 f 0.81.

Jan 1, 2015

By T Berryman, C Adams, L Griesel, C Buxton

The Kalgoorlie Consolidated Gold Mines (KCGM) schedule model is used for short- to medium-term planning and scheduling at the Fimiston Open Pit Mine (the Superpit). The model bridges the gap between grade control models, which are generated one to seven days prior to mining, and the annual Resource and Reserve model update that is used for budget and life-of-mine plans. The schedule model uses close-spaced grade control data (up to 20 000 m drilled each month) as well as resource definition drilling to estimate production volumes three to six months ahead of current mining. From this, a rolling 12 week mining and processing schedule is generated on a monthly basis. As the KCGM operation is mill and sulfur constrained, the schedule model needs to be an accurate predictor of ounces as well as tonnes, gold and sulfur grades. The process must also be time efficient in order to meet monthly planning and reporting deadlines. Due to the large amount of new data generated each month, model updates using conventional interpretation and estimation techniques have proven to be impractical and too time consuming. This paper will examine the evolution of the Superpit schedule model process over time, recent improvements and the effect of different model outcomes on short- and medium-term mine planning.CITATION:Griesel, L, Buxton, C, Adams, C and Berryman, T, 2014. The superpit schedule model – A time-efficient data-driven estimation for short- and medium-term planning, in Proceedings Ninth International Mining Geology Conference 2014 , pp 397–410 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 18, 2014

By W. Szymanski

The United States contains one of the world's largest reserves of uranium. Domestic production and exploration activities, however, have declined since the early 1980s due to weaker-than-expected growth in nuclear power demand and to foreign competition. The main result has been that more costly and less productive conventional mines and mills have closed. Meanwhile, industry productivity as measured by uranium output per employee has increased threefold since 1980. At the end of 1992, only six plants, all nonconventional, were operating in the United States. Due to cost considerations and increased environmental awareness, any additions to existing capacity are expected to be met through nonconventional in situ leach plants.

Jan 1, 1994

By I. M. London, G. P. Hatch

The Canadian Rare Earth Elements Network (CREEN) was formally launched at the Rare Earth Symposium at The Metallurgy and Materials Society of CIM (MetSoc) Conference of Metallurgists in October 2013. CREEN is an industry-led, multi-stakeholder network focused on providing collaborative solutions that will advance Canada’s REE sector to produce a significant proportion of the global production of separated critical rare earth products by 2018. The Network is industry driven by companies with REE projects under development and supported by universities, engineering firms, national and commercial laboratories, and government. CREEN aims to accelerate the development and delivery of timely solutions to technical and economic issues specifically facing Canada’s emerging rare earth sector. It will facilitate partnerships with other national and international organizations to leverage existing research initiatives. It will also support training and education to ensure that the needed qualified human resources are available to achieve the sector’s goals. CREEN membership spans the full rare earth supply chain and technical support organizations, from prospective producers, advanced project developers, national and commercial laboratories, engineering consultants, university researchers, and other innovators. This paper provides an update on CREEN's developing networking and project develop

Jan 1, 2014

By Michal Topolnicki

"Discussed is the use of wet Deep Soil Mixing, generally executed with single mixing tools 0.8 to 1.6m in diameter, employed in the foundation of viaduct supports. The applications involve economical patterns of ground improvement, covering in average about 40% of the foundation area or less, which contribute to the competitiveness of DSM solutions when compared to traditional piling. The focus is on selected aspects of the geotechnical design, applicable for geo-composite systems in which the interaction between the stabilised and the native soil should also be considered. Evaluation of settlement can be carried out with simplified methods, accounting for punching effects, or with more advanced FE models in case foundation tilt or differential settlements become important. Potential bending of DSM columns should be considered when evaluating column stresses, especially when dealing with deep deposits of soft soil and/or foundations loaded with overturning moments and/or high horizontal forces. Statistical evaluation of UCS data using lognormal distribution is recommended, and a new classification system for DSM application is proposed. Field investigations and monitoring data from completed projects are also presented.INTRODUCTIONThe first applications of wet Deep Soil Mixing in foundation of road viaducts constructed across and along the newly built A2-highway in Poland took place in 2002. Following detailed analyses, it was concluded that 39 viaducts, originally designed to rest upon large diameter piles in order to reduce excessive settlement of individual supports, could also be founded directly on the ground improved with DSM columns, fulfilling all relevant requirements of serviceability and ultimate limit states (SLS and ULS, respectively). It was also noticed that shorter construction times and lower costs of ground improvement with DSM contributed to substantial economical savings as compared to classical piling. Since then, more than 250 road and railway viaducts have been successfully founded on DSM treated ground in Poland, and wet soil mixing is now seen as a reliable and widely accepted technology for this purpose. These applications, together with a parallel use of wet DSM for foundation of buildings, industrial halls and wind turbines, have drawn international attention to the state of practice of wet DSM in Poland for foundation of engineering objects. What follows is an attempt to summarise experience gained during planning and execution of DSM works for foundation of the majority of road and railway viaducts constructed in the last 13 years, with emphasis on selected design aspects and evaluation of collected data and observed performance.The design process of DSM treatment is iterative, as described e.g. in Annex B of EN 14679, and typically involves two main steps, i.e., the selection of the design strength of cemented soil, called soil-mix design, and the adoption of suitable column pattern, referred to as geotechnical design. Soil-mix design was initially based on purposely arranged simple laboratory tests, involving mixing of soil specimen with different cement types and dosages and subsequent strength testing. However, with a growing number of completed projects the accumulated field strength data of different stabilised soils have been more and more frequently used, reducing the need for preceding laboratory testing of soil-mix to special projects only. Information on cement factors utilised in Poland and the range of recommended compressive strengths for different stabilised soils, as well as on mixing tools and characteristics of the wet method applied, can be found in Topolnicki (2008). Consequently, soil-mix design is not further discussed herein. Selected aspects of the geotechnical design are the main focus."

Jan 1, 2015

By Y Öztas, S McKinley, T Baker

The Kisladag Mine, Turkey, is a large porphyry gold deposit which is mined by open pit methods. In operation for over ten years, Kisladag provides an excellent example of how attention to a geologic feature, namely hydrothermal alteration, became a very effective predictive geological tool for planning and operation. The alteration domains were initially used as a geological tool to assist with establishment of resource model domains and to guide delineation drilling, but they were soon recognised to be correlative to geotechnical characteristics (affecting pit slope angles) and metallurgical performance (heap leach recoveries). Recent developments in spectral processing allow the systematic quantification of complex overlapping alteration phases and have greatly improved the ability to rapidly define internally consistent alteration domains for geotechnical and geometallurgical purposes.Alteration at Kisladag comprises a central core potassic (K-feldspar-biotite) zone, a tourmaline-white mica enveloping zone, an advanced argillic lithocap on the deposit’s eastern side and an overprinting pervasive argillic zone. These alteration zones and their distribution were based initially on strictly qualitative, visual mineralogical logging of diamond drill core. With the need for more accurate and consistent identification of the alteration mineral suites, particularly the phyllosilicate phases, logging was augmented by systematic measurement of spectral data using a Terraspec instrument.Recently the Kisladag spectral database (over 85 000 readings) was reprocessed by the newly developed methodology (aiSIRIS™) that allows relative quantification of the spectrally-responsive minerals. Visualising this transformed spectral mineralogy at various mineral concentration thresholds using implicit modelling software (Leapfrog®) led to the creation of consistent mineralogical and alteration domains that are used for the definition of geotechnical and geometallurgical parameters. An implicit modelling workflow enables these domains to be easily updated as new data is collected while maintaining geological integrity of the model.CITATION:McKinley, S, Baker, T and Öztas, Y, 2017. Alteration at Kisladag gold mine, Turkey – a progressive study in geology, geotechnics and geometallurgy, in Proceedings Tenth International Mining Geology Conference 2017, pp 51–62 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

By Andréa Lagacé

"The milling of sulphide ores inherently generates “thiosalts”, a series of partially oxidized sulphur oxyanions (S2O3 2-, S3O6 2-, S4O6 2- etc.), which make control of effluent treatment systems difficult because their natural oxidation produces acid with the potential to lower the pH within the treatment system and/or receiving environment.At the Xstrata Copper Kidd Metallurgical Site, thiosalt oxidation in the Tailings Management Area continues after buffer storage Ponds A and C where lime is added to precipitate metals and elevate the pH to within the required range for discharge. If the additional acidity generated during the continued process of thiosalt oxidation is not neutralized there is a risk that the final effluent will be non-compliant with regulated standards.To mitigate this risk, in 2007 a full scale pilot trial was conducted with hydrogen peroxide in order to force the complete oxidation of thiosalts prior to the lime treatment stations. This method of chemical oxidation had been shown to be effective at Xstrata Zinc’s Brunswick Mine. The pilot results indicated that a maximum of 50% of the stoichiometric quantity of hydrogen peroxide is required to reduce the thiosalt concentration in the No. 2 thickener overflow stream (feed to buffer storage Ponds A and C) to less than detection (10 mg/L); however, treatment was only effective in the presence of a 20 mg/L iron (Fe) catalyst. Since the hydrogen peroxide addition point at the No. 2 tailings thickener overflow typically contains <1 mg/L total Fe, a second reagent, ferric sulphate, was used to increase the total Fe concentration to the required level. This paper describes the set-up and results of the pilot trial which were used in the design of the full-scale plant.INTRODUCTIONTailings Management Area OverviewXstrata Copper’s Kidd Metallurgical Site, located in Timmins, Ontario, is an integrated metal refining facility producing copper, zinc, cadmium, indium, liquid sulfur dioxide, and sulfuric acid from third party custom feeds, and mineral concentrates recovered from its 7,800 tonne per day mill."

Jan 1, 2010

By Z. J. Fink

Ultraviolet-visible and infrared emission spectra from propagating methane-coal-dust-inhibitor mixtures have been obtained in a 0.2-by 0.2¬by 5.3-m vertical duct over a range of flame speeds from 2 to 100 m/sec. Results serve as a basis for the design and evaluation of thermal radiation detectors for triggered barriers that suppress ongoing mine explosions. Of particular significance is the large continua superimposed on the methane-air spectra when small amounts of coal dust are present and the variation of emissivity with infrared (IR) wavelength in dust flames. In conjunction with the spectral measurements, studies of flame speed, particle size, gas sampling plus thermodynamics, and dust sampling are presented and discussed in order to gain insight into the more fundamental aspects of propagating explosions. Sampling results have shown that only a near-stoichiometric amount of dust is consumed in the flames studied even though initial concentrations are five times stoichiometric. Difficulty in propagating coal-dust inhibitor flames of realistic mine characteristics in a cold-walled laboratory duct has been encountered. A simplified analysis of the flame zone utilizing spectral and sampling results indicates that the stability of slowly propagating flames is more dependent upon thermal radiation than upon convection losses to the walls. It is predicted that thermal radiation losses will make any measurements of coal dust burning velocities, "quenching diameters," or flammability limits more apparatus dependent than those corresponding to gaseous fuels.

Jan 1, 1974

In the Ngakuru area, zeolite deposits occur in late Quaternary lake sediments and ignimbrites. The deposits are associated with sinters, hydrothermal eruption breccias, and quartz-adularia altered fault breccias: all indicators of a shallow epithermal environment. Several of the deposits are adjacent to epithermal gold prospects. Zeolites are most abundant in lacustrine tuffs of the Ngakuru Formation, a 100-300 m thick sequence of siltstone, tuff, diatomite, sandstone and conglomerate. The formation overlies the Ohakuri Ignimbrite dated at c. 270 Ka, and is unconformably overlain by alluvial sands and gravels which are younger than 20 Ka. Individual zeolite deposits contain 30-80 per cent zeolite over a thickness of up to 45 m in thinly stratified tuff beds. The tuff beds are locally overlain by diatomite. The tuffs are composed mainly of glass shards and pumice clasts, with minor volcanic plagioclase, quartz and biotite crystals. Glass shards in the tuffs are replaced by the silica-rich zeolites mordenite and clinoptilolite. Amorphous silica (opal A), opal-CT, K-feldspar and smectite are also present. The distribution of the Ngakuru Formation is controlled by northeast trending normal faults, which separate it into the Ngakuru and Guthrie grabens. A silicified (quartz-adularia altered) hydrothermal breccia along one of the fault zones suggests that the faults acted as feeders for heated water that caused the deposition of the zeolite minerals. Some of the zeolite deposits are adjacent to sinters and hydrothermal eruption breccias. The location of the sinter about 20 m above one deposit indicates that the zeolites were formed at a depth of 20 to 70 m below the paleosurface. The hydrothermal eruption breccias contain clasts of altered ignimbrite, which contain geochemically anomalous gold and silver values. By analogy with their occurrence in active geothermal systems in the Taupo Volcanic Zone, mordenite and clinoptilolite in the Ngakuru deposits probably formed at temperatures of 60-150oC from near-neutral pH waters as a result of interaction with glass-rich tuff beds. The Ngakuru zeolite deposits are therefore interpreted as shallow hydrothermal alteration zones within larger epithermal gold-bearing systems.

Jan 1, 2002

By Michael McNinch, LaTasha R. Swanson, Jennica L. Bellanca, Justin Helton

Accident data indicates that mobile haulage poses a significant pinning, crushing, and striking risk. Proximity detection systems (PDSs) have the potential to protect mineworkers from these risks. However, unintended consequences of mobile PDSs can undermine the safety benefit they provide. Soliciting iterative user input can improve the design process. Users help provide a critical understanding of how mobile PDSs may hinder normal operation and endanger mineworkers. Researchers explored users’ perspectives by conducting interviews with mineworkers from seven mines that have installed mobile PDSs on some of their haulage equipment. Mineworkers reported that mobile PDSs affect loading, tramming, section setup, maintenance, and general work on the section. Mineworkers discussed the operational effects and increased burden, exposure, and risk. Mineworkers also suggested that improved task compatibility, training, logistics, and PDS performance might help address some of these identified issues. This paper also gives additional insights into mobile PDS design and implementation.