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By M. Mostert

Mining companies sponsor a range of non-core, corporate social responsibility projects to adhere to social and labour plans and environmental management prerequisites that form part of a mining licence application. Some companies go above and beyond such projects, sponsoring initiatives that generate renewable energy through solar power, wind energy, natural gas, etc. The challenge for these companies is to choose between a variety of projects to ensure maximum value, especially in times when the economic climate might be less favourable for such projects. The focus of this research was to analyse the concept of sustainability as it exists today, and to apply that to the triple bottom line accounting method in an attempt to quantify the sustainability of a project. Research was done on the methane burn-off project at Sibanye Gold?s Beatrix Mine to establish how such projects are planned and financed, and what impact they have on the triple bottom line of a company. The financial bottom line is, by definition, one that executives understand. This paper also proposes a quantitative method for defining the social and environmental bottom lines as well. By considering the financial, social, and environmental values, the study attempts to determine a monetary value for a sustainable renewable energy project. This monetary value can be compared to similar values obtained for other sustainable renewable energy projects under consideration. The research suggests that monetary value alone is not enough to base a sustainable decision on, and qualitative measures are suggested for use in conjunction with quantitative methods. The selection method proposed should assist the board of a mining company to choose the most sustainable option and the project that will add the greatest value to the company across all three bottom lines. It will also provide increased justification for such renewable energy projects, even in periods of harsh or uncertain economic climates.

Jan 1, 2014

Recycling and Recovering Fine Particles from Auto Shredding Residue (ASR/SR) to Conserve Raw Materials and Protect Environment

Sep 13, 2010

By Rudi Podjadtke

In a short chronological review the development concepts and improvements in steel roadway support are shown. The successful standardization concept of RAG Deutsche Steinkohle and currently used support systems are important topics. The history of optimizing the material properties for the steel arch support with different alloys up to the tempering used today is discussed. The present-day application of the steel support is additionally presented. Today, it represents a system component of modern roadway support also for highly stressed roadways. In addition to the yielding roadway arch support, this overall system - the combination support - consists of the additional components of a rockbolting system and concrete backfilling. The comparison of the application areas for each individual partial system with the overall system illustrates its high performance capability. Actual practical experience with the state of the art typed steel arches are pointed out exemplarily. Understanding the complete system permits the selection of the economically optimal support for all conditions.

Jan 1, 2008

By L. R. Raymond

With the trend toward deeper and consequently hotter holes, measurements of drilling mud properties at atmospheric temperatures are becoming increasingly inadequate.' Both the prediction and control of down-hole mud properties depend in part upon our knowledge of temperatures in the wellbore. Consequently, a better understanding of factors that affect temperatures during circulation and trips could improve drilling operations. It was toward the goal of obtaining this understanding that this study was directed. Other investigators2 have studied the response of fluid temperature in the borehole during trips. However, all of these studies have used an assumed formation temperature profile at the conclusion of circulation and have provided no means to calculate this profile directly. In this study, the formation profile during circulation was calculated. Other investiga-tors3-5 have also studied bottom-hole temperature during circulation. However, they have developed neither general techniques for calculating the entire temperature profile in the system nor generalized methods for predicting bottom-hole fluid temperatures during circulation. Such techniques and methods have been developed and are discussed briefly in the following pages. Temperature Behavior During Circulation Circulation of fluid during the drilling operation is represented schematically in Fig. 1. The process of circulation has three distinct phases: (1) fluid enters the drill pipe at the surface and passes down the drill pipe; (2) fluid exits the drill pipe through the bit and enters the annulus at the bottom; and (3) fluid passes up the annulus and exits the annulus at the surface. To simulate the thermal behavior of the fluid in the system, each of the phases of circulation must be described mathematically. In Phase 1, the fluid enters the drill pipe at a specified temperature, TDo. As the fluid passes down the pipe, its temperature is determined by the rate of heat convection down the drill pipe, the rate of heat exchange between the drill pipe and the annulus, and time. Phase 2 of the circulating process merely requires that the fluid temperature at the exit of the drill pipe be the same as the fluid temperature at the entrance of the annulus; i.e., TD(L,t) = TA(L,l). Thus in Phase 3, the fluid enters the annulus at TD(L, t). As the fluid flows up the annulus, its temperature is determined by the rate of heat convection up the annulus, the rate of heat exchange between the annulus and the drill pipe, the rate of heat exchange between the formation adjacent to the annulus and the fluid in the annulus, and time. These rates of heat exchange and the time dependency of mud temperature are described by well known heat-flow equation.6 Consequently, as shown in the Appendix, the temperature profiles in the drill pipe, annulus, and formation can be obtained by solving Eqs. 1 through

Jan 1, 1970

By Marc Ruest, Lewis Martin

A new instrumented cable bolt has been developed by the National Institute for Occupational Safety and Health at the Spokane Research Laboratory in Spokane, WA. Although various instruments are available to measure load distribution and magnitude along a grouted cable, this instrument is innovative in that it uses strain gauges internal to the cable as load-measuring sensors. The instrument has been successfully tested in the field at FMC’s Granger Mine, Meikle Mine, and Getchell Mine. A “split-pipe” laboratory pull test was performed on each of three cable bolts instrumented with the new device. Each test consisted of grouting a 1.83-m-long cable in two 0.91-m-long sections of schedule 80 pipe. A numerical analysis was then performed in which laboratory boundary conditions were simulated and model properties derived from textbook guidelines. The loads calculated by the model were then compared to the measured loads.

By Marc Ruest

A new instrumented cable bolt has been developed by the National Institute for Occupational Safety and Health at the Spokane Research Laboratory in Spokane, WA. Although various instruments are available to measure load distribution and magnitude along a grouted cable, this instrument is innovative in that it uses strain gauges internal to the cable as load-measuring sensors. The instrument has been successfully tested in the field at FMC?s Granger Mine, Meikle Mine, and Getchell Mine. A ?split-pipe? laboratory pull test was performed on each of three cable bolts instrumented with the new device. Each test consisted of grouting a 1.83-m-long cable in two 0.91-m-long sections of schedule 80 pipe. A numerical analysis was then performed in which laboratory boundary conditions were simulated and model properties derived from textbook guidelines. The loads calculated by the model were then compared to the measured loads.

May 1, 2002

By K Prendergast, P Dale, I Taylor, A J. Vigar, B Lueck

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Kainantu Project is located within the New Guinea Thrust Belt in northern Papua New Guinea. The area has a long history of exploration and production, with the discovery of alluvial gold in 1928 followed by the discovery of vein deposits of gold and copper at Kora in the 1950s and the current Irumafimpa vein gold mine. Current resources on the Kora-Irumafimpa Vein System (KIVS) stand at 1.5 Moz Au, 5 Moz Ag and 217 Mlb Cu.Mineralisation in the region includes gold, silver and copper associated with mid-Miocene age mafic to felsic intrusions. The KIVS occupies a broad north-west-trending mineralised zone more than 2.5 km long and 200 m wide, with the Kora, Eutompi and Irumafimpa veins on the western side and the Judd and Upper Kora veins on the eastern side. Economic mineralisation occurs in two closely related events occupying the same strongly structurally controlled shearing (quartz-Au-telluride veins and sulfide Au-Cu-Ag veins with free Au) and is best described as a significant intrusion-related event with both epithermal and mesothermal facets that does not appear directly related to known porphyry Cu-Au systems as seen at the surface. Significant wolframite is associated with vein quartz of a slightly older age but also occupies the same shear system.The KIVS occurs within a larger mineralised area of approximately 5 × 5 km. It has complex multiphase intrusions, breccias and diatremes that are only partly delineated by drilling and comprises multiple occurrences of Au-bearing veins and porphyry Cu-Au mineralisation. The area is considered to have high potential for extending the current resources and is being actively explored. The proposed recommencement of mining activities recognises the complexity of the KIVS and later disruptive faulting and will require tighter grade control systems, targeted mining techniques and a gravity circuit to maximise free Au recovery.CITATION:Vigar, A J, Lueck, B, Taylor, I, Prendergast, K and Dale, P, 2015. Kainantu gold-copper system, Papua New Guinea, in Proceedings PACRIM 2015 Congress, pp 601–606 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By I. A. Mutemererwa

This paper investigates the role of vertical integration between chrome ore mines and ferrochromium smelters in the location of ferrochromium production capacity in South Africa and Zimbabwe. Vertical integration is important in understanding the increasing competitive position of these two countries as observations show that an increasingly larger share of the global market has been coming from integrated producers. The paper argues that the increased vertical integration between mines and smelters in South Africa and Zimbabwe has led to a lower cost of chrome ore as an input compared with other producers. Underlying this hypothesis is the basic tenet that, more likely than not, production will take place where the costs are lowest. The paper concentrates on high carbon ferrochromium (HCFC) production in market economy countries (MEC). Using an ordinary least squares model, the study tests the relationship between low chrome ore costs and vertical integration shows a statistically significant relationship. These findings partially support the view that the control of sources of chrome ore is a major source of competitiveness. Keywords: competitiveness, ferrochromium (ferrochrome), ordinary least squares, dummy variables, vertical integration, southern Africa.

Jan 1, 2000

By Anthony Iannacchione

Coal mine bursts have represented a major hazard for U.S. mining operations for more than 90 years. During this time, many prevention controls have been developed and tested. This paper reviews 11 prevention control techniques. Although coal mine bursts are not common events in most underground coal mines, their occurrence almost always requires a change in mining practice. Over the many years of dealing with these hazards, specialized requirements for layouts and novel extraction sequences have been developed on a site specific basis. The keys to mitigating risks are to properly assess the coal burst hazards and to possess the knowledge and skills to prevent or remediate their occurrence.

Jan 1, 2008

By Zhang Chuanfu

Keywords: modified coprecipitation method, Ni-Co alloy powders, solid-solution oxalate, growth mechanism Homogeneous solid-solution oxalates of Ni2+ and Co2+ ions were synthesized by modified coprecipitation method and the composition and morphology of the fibrous solid-solution oxalates precursor were characterized by XRD, IR, DTA/TG and SEM analysis. The effects of feeding methods, pH values, precipitation temperature, reactant concentration, addition surfactant, alcohol washing and drying process on the morphology and dispersion of the precursor were investigated in detail. The experimental results showed that the coprecipitated powders have characteristics that are different from those of the mechanical mixtures with the same stoichiometry. Based on the observations of precursors growth and SEM morphology of the precursor, the oriented attachment was proposed for the well-aligned growth of the fibrous Ni-Co alloy precursor particles.

Jan 1, 2005

By J. S. Peterson

Occupational noise-induced hearing loss (NIHL) has been recognized by the National Occupational Research Agenda (NORA) as the most common job-related disease in the United States. Roughly 30 million workers are exposed to excessive noise levels or toxins that are potentially hazardous to their hearing. The National Institute for Occupational Safety and Health (NIOSH) Office of Mine Safety and Health Research (OMSHR)is investigating noise controls to reduce operator overexposures caused by haul trucks used in underground metal/non-metal mines. To identify the most significant contributors to the overall sound level, Source Path Contribution (SPC) analysis was conducted. Noise dosimetry and time-motion analysis were also conducted to quantify operator noise exposure. SPC analysis determined that, under high idle conditions, a source near a hydraulic pump mounted to the rear of the engine and the engine cooling fan were the major noise sources. The time-motion/dosimetry analysis showed that the operators accumulated more than 90% of their noise exposures while they were hauling ore to the dump site and traveling back to the load site unloaded.

Jan 1, 2012

By T. T. Chen

The behavior of gold in a conventional copper electrorefinery anode slimes treatment process is expounded on in this study. In the raw anode slimes generated in a copper electrorefinery, gold occurs mainly as tiny particles of metallic gold, which are commonly attached to selenide particles. Some gold is also present in selenide form. Decopperizing the anode slimes retains much of the metallic gold, but also promotes the incorporation of gold in the structure of silver-rich selenide species. A greater fraction of the gold is converted to (Ag,Au)2Se or Ag3AuSe2 when high-Se and high-Ag anode slimes are decopperized at elevated temperatures and pressures. After pelletization and roasting of the slimes, the gold is converted to a (Ag,Au)-alloy and Ag3AuSe2. Smelting of the roaster products eliminates the selenium and converts the gold to a silver-rich (Ag,Au,Pd)-alloy in the dore metal. In the subsequent silver electrorefining process, gold collects as a gold-rich (Au,Ag,Pd)-alloy in the gold mud. Dore smelting rejects many impurities as a silica slag; minor amounts of gold are present as a (Ag,Au,Pd)-alloy in the silica slag. This gold is recovered by flotation and is recycled to the dore furnace. Gold is identified in both the tellurium caustic leach residue and the parting plant wash water mud as tiny particles of metallic gold. These products are also recycled to the dore furnace to recover their gold values.

Jan 1, 2008

By D Craw, I M. Turnbull, R J. Norris, N Mortimer

The Otago Schist is being subdivided on a regional scale into structurally, metamorphically and lithologically distinct blocks. Differences between blocks are subtle, and difficult to map in the field. Boundaries are late-metamorphic or immediately post-metamorphic in origin, and are different from later brittle faults which disrupt the schist. Mapping of late-post-metamorphic structural discontinuities has direct application for basic grassroots exploration in the Otago Schist. The mineralised (and currently mined) Hyde-Macraes Shear Zone forms a regional scale boundary between a block dominated by politic schist and a block with massive psammitic schist, pelitic schist, and minor greenschist and chert. The HMSZ forms a metamorphic discontinuity, with garnet and biotite in the underlying schist, and neither index minerals apparent in the overlying schist. The HMSZ is also a structural boundary between domains with differing lineation orientations. The HMSZ can not yet be traced along strike to the northwest to the Rock and Pillar Range, where the only major discontinuities recognised are the Caples-Torlesse boundary and a normal fault separating low grade from high grade schist. Structural and lithological discontinuities in the Dunstan Range break the range up into distinct structural blocks, two of which are separated by the gold-mineralised Rise and Shine Shear Zone.

Jan 1, 1999

The study of gas emitted from face coal samples at the coal face is part of an investigation of instantaneous outbursts of coal and gas. Normally, seam gas essentially comprises methane of which the origin in the metamorphism of coal is undoubted. The origin of other gases sometimes occurring in high proportion in seam gas, particularly carbon dioxide, is more controversial. A simple meter for rapidly assessing gas in coal was developed. Tests with the meter enabled comparisons of seam gas in face coal at some outbursting and nonoutbursting mines, and under various working conditions. The varying results of widespread testing suggest certain trends, including some prospect of recognising outbursting potential at the coal face.INTRODUCTIONThe aim of this work is identification of differences in gas condition between coals subject to instantaneous outbursts and coals which have not outburst, and between faces of coals which will and which will not subsequently outburst. Any comparative test should be conducted right at the coal face on coal about to be worked and the results of testing should be available after a short period. Moreover, the method and the comparison of results should require no special skill, and be well within the capacity of junior mine officials. Any consistent relation between gas condition and subsequent mining conditions - outbursting or not might be valuable in prediction of outbursts.INSTANTANEOUS OUTBURSTSInstantaneous outbursts (Hargraves, 1958) , are largely unpredictable and unaccountable ejections of coal (up to 5,000 tons) and gas (up to 5,000,000 cu.ft.) from a standing coal face. Usually the gas is essentially methane (CH4 ) but may be essentially carbon dioxide (C02 ), or an intermediatemixture...

Jan 1, 1962

By H. O. Hofman

At the Lake Superior meeting, September, 1904, Messrs. A. Gibb and R. C. Philp presented a paper entitled " The Constitution of Mattes Produced in Copper-Smelting,"' in which they concluded that ferrous and cuprous sulphides formed the chemical compound, 5 Cu2S, FeS. They arrived at this inference from the observed fact that a matte containing Cu,S, 90.4, and FcS, 9.6 per cent. (or, in round figures, Cu2S, 90, and FeS, 10 per cent.), did not contain any metallic copper, while one with more than 10 per cent. of FeS readily dissolved copper, and with less than this amount retained copper in mechanical suspension. Although they determined the melting-points of five mattes containing from 32.6 to 80.1 per cent. of copper, they did not draw a freezing-point curve, as the necessary apparatus was not available. A microscopical examination of 11 polished samples gave them a grayish-black field of very uniform appearance, except that five of the specimens showed the presence of metallic copper. The object of the present investigation was to supplement the above paper by drawing the freezing-point curve of the ferrous sulphide-cuprous sulphide series, and to see how the constitution could be further revealed by microscopical work. The results obtained lead to conclusions very different from those of Gibb and Philp. While their paper bears the date 1904, it was published only in 1906.2 In the meantime, Bolles3 had presented his paper, " The Concentration of Gold and Silver in Iron-Bottoms." The raw material which formed the basis of the research was a matte containing Fe, 61.68, and Cu, 11.20

Jan 1, 1908

By Jackson R. Pressley, M L. Hopkins, R E. Danell, N T. Moxon, Andrew Bowman

Efficient and cost effective blasting is achieved by closely matching the explosive energy to the strength of the material in which it is being used. Although there are many empirical relationships wich approximate this situation complete the blast optimization can only be achieved by quantitatively assessing explosive/rock interactions and explosive performance. The performance of an explosive is essentially governed by its velocity of detonation or the rate at which the detonation wave travels through the explosive column.

Jan 1, 1991

Water Balancing in Mineral Processing - Issues and Opportunities

Sep 13, 2010

By John C. Stankus

At the 13th Conference on Ground Control in Mining, a paper was presented detailing a successful test in which a new truss system was utilized, in lieu of wood cribs, for tailgate support in the Pittsburgh seam (Stankus et al., 1994). Since that time, additional tests using this same truss system in the Pittsburgh and other seams are now complete. Also, several mines are now using trusses for full panel tailgate support with no cribs. Through an extensive instrumentation program, much data and new information has been gained from these tests and the full panel usage. From this data, not only have new concepts pertaining to tailgate support been developed, but also for headgate, pillar configuration, primary and supplemental support. In this paper, an update will be presented summarizing the results of these various tailgates.

Jan 1, 1995

By J. Yuan

Ground calcium carbonate (GCC) and chemically precipitated calcium carbonate (PCC) have become important mineral-based commodities in recent years. GCC manufacturing generally requires high purity and high brightness deposits of marble, chalk or limestone as the stone source. PCC usually uses limes made from lesser quality limestone deposits. GCC products have a wide span of particle size, with a d50 size ranging from sub micrometers to as large as several inches such as those used in landscaping. PCC products are typically limited to less than 10 µm (1,250 mesh). Each PCC product has a narrowly distributed size range. GCC and PCC products tend to have higher levels of whiteness com-pared with other traditional filler and extenders, such as kaolin and talc. Published statistics of GCC production volume often vary due to the exclusion of certain size range GCC products. According to Roskill’s latest estimate, world GCC capacity was believed to exceed 56 Mt (62 millionst) during 2004 for all grades.

Jan 1, 2005

By Xiaowen Liu

The DSC/TG, IR and XRD analysis were used to characterize the heating phase transformation of illite, which came from Ouhai deposit, China. It was discovered that the dehydration and de-hydroxylation of illite carried out stage by stage during heating. The adsorptive water and layer-inter water were dehydrated from room temperature to 500°C; and dehydroxylated in the range 500°C~800°C. In these stages of process, illite?s layer structure kept almost unchanged. After 800°Cillite began to change into disorder structure. At about 1100°C, the layer structure of illite had been destroyed, and amorphous SiO2 and mullite crystallite appeared. At about 1200°C the structure of illite completely destroyed and mullite crystal phase had become perfect..

Jan 1, 2006