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By Terry J. Close

A mineral resource survey of the 236-mil (611-km2) Hyalite-Porcupine-Buffalo Horn wilderness study area (RARE 11 Areas No. 1-155 G, Gallatin Divide; and H, Hyalite) between the Gallatin and Yellowstone rivers in Montana, indicates there are phosphate rock and petrified wood resources (fig. 1). The area also has some potential for oil, gas, and geothermal resources. Stone and alluvium are abundant but appear to have little potential for development because other sources are available nearer to markets.

Jan 1, 1981

By Frank G. Horino

Drill cores from 18 exploratory holes that were drilled into the unleached saline beds were tested for mechanical properties by the Bureau of Mines. Test cores were primarily selected from zones L4B, R4B, L3, and R3A in the Piceance Creek Basin, Rio Blanco County, Colo. Regression analysis techniques were tried in an attempt to relate kerogen yield or apparent specific gravity to the parameters compressive strength, Young's modulus, and Poisson's ratio. Correlation coefficients were very poor, indicating that this type of analysis was not amenable to these data. Analysis of variance techniques were tried using a division of either greater than or less than 10% nahcolite together with the requirement of less than 3% dawsonite. Results showed that a larger percentage of nahcolite tended to lower the compressive strength and to increase Young's modulus. A second analysis was made using a division of less than 3% dawsonite and greater than 3% dawsonite together with the requirement of less than 1% nahcolite. For this analysis, a larger per-centage of dawsonite tended to increase compressive strength, Young's modulus, and Poisson's ratio. Mean compressive strength values were determined for the mining horizons of interest. Average physical properties for design purposes were also determined for the horizons of interest and for a proposed adit based only on logged geologic depths to these horizons. No consideration was given to percentages of nahcolite and dawsonite. Creep data obtained from nahcolite-and dawsonite-rich oil shales provides a best fit to a modified power equation.

Jan 1, 1978

By Keith R. Vining

Solid fuel, usually coke or anthracite, is commonly added to ground iron ore fines in the pelletising process to reduce the amount of burner fuel required and the maximum firing temperature, while maintaining pellet strength and the productivity of the pelletising plant. However, the use of coke and coal contribute to the production of greenhouse gases (eg carbon dioxide) and are a source of NOx and SOx emissions. Utilising wood biomass / wood char is one methodology CSIRO Minerals is investigating as an alternative to coke and coal, as it is a renewable energy source that is very reactive, has a low ash content and the potential to reduce emissions of greenhouse gases from the iron and steel-making process. Previous work has established that charcoal can effectively replace coke in the sintering process (Lovel et al, 2005), and the following experimental work aims to demonstrate that it can also provide an adequate replacement for coke and coal in the pelletising process. The paper presents the results of an experimental testwork program comparing the behaviour of fired pellets containing traditional solid fuels and charcoal. The physical properties of the pellets are compared in terms of their compressive strength, tumble and abrasion indices and the reduction properties. A qualitative assessment of the pellet microstructures is also presented.

May 1, 2007

By M. J. Leeuwner

Computational fluid dynamic (CFD) modelling is used to research the complex flow structures that exist in a hydrocyclone. By simulation of a two phase (water and air) flow system, the internal flow and multiphase interactions are investigated. The suitability of CFD modelling as a design tool is further evaluated by examining the effect of varying device dimensions. Three hydrocyclone geometries, used in previous studies, are specified. A transient simulation approach, which employs the Reynolds Stress Model as turbulence model and the Volume of Fluid model as multiphase model, is followed. Results are validated qualitatively against experimental measurements from the previous studies. Keywords: CFD modelling, hydrocyclone, Reynolds stress model, multiphase flow

Jan 1, 2008

By T M. El Hajj, A C. Chieregati, M T. G C Marques, J M. Braga Jr, H Delboni Jr

"The estimate and control of sampling errors is essential for all mining operations, especially when dealing with strategic materials, such as niobium. This paper is based on a traditional quality assurance and quality control technique used to confirm mineralised intersection zones, and proposes the validation of sampling data using diamond drill twin holes, in order to evaluate and improve the quality of the current data set. The geological model of the niobium mine – located in Araxá, Minas Gerais, Brazil – was built including 77 diamond drill holes of a sampling campaign carried out during the 1970s. There are few records about the collection and preparation procedures of these past samples, making it difficult to estimate the errors associated with their analytical results. Therefore, 11 twin drill holes were drilled to compare their samples against the samples from the 1970s drilling campaign. The new hole locations were chosen as near as possible to the old holes location. The JORC Code, 2012 edition, relates the use of twin holes as a good sampling technique to assess sampling and assay data. Three parameters were considered to validate the 1970s drill hole campaign by the twin drill hole campaign: the difference of the coordinates between the paired holes the difference among the positions of the geological contacts to validate the geologic description the difference between the paired samples grades was calculated to validate the analytical results.The analysis of the grade range variation between sample pairs was based on three techniques: geostatistical interpretation of vertical semivariogram to obtain the nugget effect calculation of the relative difference between duplicates calculation of the error associated with the sampling protocol established according to Pierre Gy’s Theory of Sampling.The results were satisfactory for hole coordinates; however, the ore content showed a high deviation, although this divergence can be explained by the nugget effect. For the lithological intervals, the new results contributed to an effective identification of variations among lithologies, ie brown weathered ore and saprolite. The twin drill holes campaign successfully validated the geological model data, allowing effective mine planning and higher reliability of the reconciliation results.CITATION:Marques, M T G C, El Hajj, T M, Braga Jr, J M, Chieregati, A C and Delboni Jr, H, 2017. Theory of Sampling and geostatistics for twin drill holes analysis in a niobium mine in Araxá, Brazil, Australia, in Proceedings Eighth World Conference on Sampling and Blending, pp 97–106 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

May 9, 2017

By R. A. Bosch, F. V. Lenel, G. S. Ansell

RECENTLY, Ansell and aenel' proposed a dislocation model to account for the yielding behavior of dispersion-strengthened alloys. The criterion for yielding used in this model was that yielding occurs when the shear stress due to arrays of piled-up dislocations fractures or plastically deforms the dispersed second-phase particles. Calculations based on this model predict that the yield strength, uysof a dispersion-strengthened alloy containing particles whose geometry permits them to be considered as straight, i.e. not curved, barriers to dislocations follows the relation where and are the shear moduli of the matrix and dispersed phase respectively, b is the Burger vector of a dislocation in the matrix, A is the mean free path between dispersed phase particles and C is a constant. This yield stress, ys, is closely approximated in polycrystalline alloys by the proportional limit. The offset yield stress, uoy, is the yield stress, uys, plus the increase of stress due to strain hardening in the offset strain increment. Previous investigation1 has shown that Eq. [I] describes the yielding behavior of several different dispersion-strengthened alloys as a function of the mean free path between dispersed phase particles at a constant temperature. The purpose of this investigation was to investigate the temperature dependence of the yielding behavior of dispersion-strengthened alloys. The alloys studied, MD2100 and MD5100, are SAP-type alloys containing flake shaped aluminum oxide particles dispersed in a matrix of commercial purity aluminum. The proportional limit and 0.2 pct offset stress of both of these alloys were determined as a function of temperature over the temperature range from -190" to 500 C. All tests were conducted on an Instron tensile testing machine. Stress was measured by means of the Instron load cell. Strain was measured by means of SR-4 strain gages attached to the tensile specimens. Stress sensitivity was 80 psi. Strain sensitivity was 2 x 10F Fig. 1 shows the values received for the proportional limit and 0.2 pct offset yield stress plotted as a function of homologous temperature for both the MD2100 and MD5100 alloys. Inspection of Eq. [I] shows that of the terms which determine the theoretically predicted yield stress, uy,, only the shear moduli have an appreciable temperature dependence. From Eq. [I] the yield stress at any temperature T, UT, may be predicted from the yield stress at any arbitrary reference temperature, in this case 25 OC, u25, by the relation where the subscripts T and 25 refer to the values of the property at test temperature and at 25"C, respectively. The temperature dependence of the yield stress predicted by Eq. 121, based on the observed value for the proportional limit at 25OC, is also shown in Fig. 1. In evaluating Eq. [2] the following data was used. The values for the shear modulus of

Jan 1, 1962

By Y. G. Qin

In this article an experimental study of axial bearing capacity of half-closed steel pipe pile installed at BKSH dock is presented. In comparison with open and closed end piles, half-closed end pile is considered to have high bearing capacity and good penetration, that is, it not only has a capacity as twice as the same size open end steel pipe pile, but also has blow counts as half as the same size closed end steel pipe pile. It is economic to use half-closed end pile in soft ground without a deep deposit of thick stiff clay. This article also describes a large scale model pile test and preliminarily analyses mechanism of improvement of bearing capacity of half-closed end pile with emphasis on effect of squeezed soil on side friction; an empirical approach is presented in which side friction is related to density of squeezed soil and which is useful for reasonably chosing side friction of different types of piles in design of foundarion.

Jan 1, 2010

By William M. Gleason

Hard times continued to plague the industry when the calendar rolled over to 2000. During 1999, the United States economy had grown vigorously, capping the longest economic expansion in United States history. However, the mining industry was not so fortunate. Commodity prices remained in a slump in the “new-economy” that was fueled by excitement and speculation about the power of the Internet during the infancy of the Information Age. Much of the investment money that once went to mining and exploration was now headed to the world of virtual gold mines. SME President Donald E. Ranta implemented new technology into his plans for SME. His two major goals were new membership growth and to foster the establishment of the comprehensive Internet presence for the Society’s technical information. His strategic priorities included enhancing the quality and quantity of publications, programs, meetings and short courses. “The Internet is the vehicle that will advance the priorities,” he said.

Jan 1, 2007

By J Fisher, M Castro, A Hariyadi

The train haulage system being designed for PT Freeport Indonesia’s Grasberg Block Cave (GBC) will be located within the mine at an elevation of almost 3000 m above sea level on the west side of the island of Papua, Indonesia. The developing block cave is beneath the active Grasberg Open Pit and will transport 160 000 t of ore per day from multiple chute galleries to the underground crushing plants. The design entails 28 km of rail and 119 ore chutes, which will be brought online over the course of ten years.The train haulage system will be driverless and fully automated. Sequentially, the system includes remote controlled rock breakers at the top of the chute grizzlies, followed by remote controlled chute loading of the trains, then autonomous train haulage and autonomous unloading. An overhead catenary system (OCS) will power the locomotives, which are equipped with on-board batteries to drive through the loading and unloading sections. Service locomotives with drivers move material-laden freight cars in and out of the service shaft, destined for workshops, the magazine and batch plants. Service locomotives are also used for haulage level maintenance. Highly reliable and redundant control and communications systems are required to manage 12 trains in simultaneous operation.This paper provides an overview of the train haulage system’s technical complexities and the associated support systems interactions. The paper also highlights the project management issues and successes of this globally sourced project.CITATION:Hariyadi, A, Castro, M and Fisher, J, 2016. Automated train ore transport, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 563–570 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By D Frantzos, J J. Cotter, H Tammemagi, J B. Codrington, J Kaasalainen, A C. Webster

"Exploshres Technologies International (ED) is developing an instrument called ROCSCAN which isplanned to have broad application in both blasting and rock mechanics. The purpose of this paper is to outllne the background that has led to the development of ROCSCAN, describe its objectives and to present a progress report on the work to date. Some of the potential applications of ROCSCAN will also be reviewed."

Jan 1, 1989

By S J. Brace

About 180 000 tons of explosives are used annually underground in South Africa. Most is loaded into holes less than 50mm in diameter. 75% is consumed in the gold and platinum mines where holes are between 25 and 4omm in diameter and no more than 3.0m in length. The small amount of explosives per hole with extreme conditions of heat, humidity and seismic activity, make the choice of explosive on safety and technical grounds very important to the success of a blasting operation. Taken together with the fact that many underground precious metal operations are now marginal then the choice of an explosive, when its price is also considered, becomes critical to the very viability of some mines.

Jan 1, 1994

By M P. Simpson

Forty one whole rock samples from the Gold Cross low-sulfidation epithermal Au-Ag deposit have d18O values that range from 4.4 to 9.3 per mil, with an average value of 7.0 per mil. Unaltered and weakly altered rocks have d18O values greater than eight per mil, and the orebody is surrounded by samples that are depleted in 18O. A strongly silicified sample adjacent to the Empire Vein System has a d18O value of 9.0 per mil, similar to previously reported analyses of vein quartz (7.0 to 11.7ë, average 9.4ë). This suggests that, in detail, Golden Cross may have a zone of 18O-enriched wall rocks in the core of the deposit, adjacent to the main underground veins. Although some workers have suggested that stable isotope geochemistry may provide useful information for epithermal mineral deposit exploration, at Golden Cross this is not the case. Alteration minerals, major elements and trace elements all define larger, less ambiguous halos than the zone of 18O-depleted wall rocks.

Jan 1, 2001

By Fred C. Schmednecht

For years, the strategy was to contain waste and in many applications, is still the recommended method. Recently, it has become acceptable to create filters below ground for the in-situ treatment of waste. Consequently, in lieu of the waste being contained, it is desirable that the waste flow through a pervious treatment zone. For instance, subterranean pervious walls comprised of iron sand are particularly useful in treating chlorinated solvents in contaminated groundwater. The iron acts as a corrective filter to treat the contaminated groundwater. How are these impervious and pervious walls being constructed? One effective means of constructing an impervious barrier is the vibrated beam method. This method, in brief, involves the use of a fabricated steel beam, a vibrator, a pile driving crane, and a mixing plant. This method results in a 4-6" wide wall with depths up to and exceeding 100'. Over one hundred slurry walls have been installed using this method in the United States. The need for the vibrated beam method continues to escalate due to its reduced health and safety considerations, high level of quality control, lack of excavation, narrow working area, and ability to achieve depths greater than 100'. A recent project was in Marinette, Wisconsin at the ANSUL facility. The project consisted of a 28,000 square foot slurry wall and was completed in January of 1999. Another effective means of creating an impervious barrier, where structural support from the barrier is needed, is the Waterloo® Barrier System. This system involves the use of a pile driving crane, Waterloo® steel sheet piles which are patented steel sheet piles due to their groutable interlocks, and a grout plant. This system results in a water-tight barrier due to the grouted interlocks and provides structural support. A project was completed at Beta Steel in Portage, IN for a retention pond to protect Lake Michigan. Due to the new concept of "filtering", there are few accepted construction techniques available. One effective field proven construction technique is the patent pending mandrel emplacement technique. This technique involves the use of a fabricated hollow steel mandrel with a shoe, a vibrator, a heavy duty crane, and a material feeder. This technique results in a pervious wall which may be comprised of pure iron sand or any other flowable media. Using this technique, the pervious wall may be constructed in varying widths to depths in excess of 100'. A successful installation occurred in October 1997 at Cape Canaveral Air Station in Florida.

Jan 1, 1999

By Miguel Pimentel

El presente trabajo describe el proceso implementado por la minera Yanacocha para el tratamiento de las aguas de exceso a través de la Tecnología de Membranas (EMS- Engineered Membranes System) o proceso de Osmosis Inversa, conocida también por las siglas en inglés de RO (Reverse Osmosis). El proceso RO tiene por objetivo tratar la solución barren proveniente de la planta de Merrill-Crowe para reducir el contenido de cianuro, así como los metales disueltos y otras sustancias como nitratos y nitritos en la solución.También, busca clarificar el agua tratada para cumplir con las exigencias que establece el Ministerio de Energía y Minas (MEM) y el Banco Mundial (IFC) en cuanto a límites de descarga permisibles. Una vez alcanzados los niveles establecidos, y con la aprobación del área interna de Control de Calidad, el agua tratada se descarga al medio ambiente.

Sep 12, 2005

By Fardy J. J

Abundance data are presented for a comprehensive range of elements in oil shale samples from deposits located in Queensland. The techniques of instrumental neutron activation analysis and spark source mass spectrometry were used to obtain concentration data for up to 50 trace elements in each shale. These techniques were supplemented by other spectrometric methods to obtain data for major, minor and some trace elements. Sixty-four elements were determined quantitatively. This comprehensive characterisation of oil shale samples from the major deposits in Australia provides inorganic abundance data not previously available. It also provides important background information for processing studies and the associated environmental aspects of shale oil production and waste disposal.

Jan 1, 1986

By P. Jurovcik, D. Yantek, D. Ingram

The National Institute for Occupational Safety and Health (NIOSH) identified hearing loss as the most common job-related disease in the United States in its 1996 National Occupational Research Agenda. Previous studies by NIOSH have shown operators of surface drill rigs without cabs are commonly exposed to A-weighted sound levels exceeding 90 dB. During hammer-drilling, A-weighted sound levels exceeding 100 dB were recorded at the operator station. NIOSH collaborated with a local drilling company to design and install a partial cab between the operator and the drill steel in an effort to reduce the sound level at the operator station. Sound level measurements in the field show the partial cab reduces the A-weighted sound level by 5-9 dB at the operator’s left ear and 2-5 dB at the operator’s right ear while hammer-drilling. This paper will briefly discuss the preliminary design of a cab and the testing of materials for construction of the prototype. Explanation of the ideas behind the prototype design and fabrication will be covered. Finally, the field test method and results will be discussed in detail.

Jan 1, 2007

By A. J. Forney

The hot-gas-recycle process, for the hydrogenation of carbon monoxide, was investigated in a 12-inch-diameter reactor. Initially because the distribution of gas was poor, hotspots developed in the catalyst bed. After the velocity profile of the gas flowing through the bed was studied, the method of packing the catalyst was altered. Because this change improved the distribution of gas, temperature control was excellent. The l2-inch-diameter reactor was operated successfully in the synthesis of gaseous and liquid fuels. When high-Btu gas was synthesized in two stages, parallel-plate assemblies of Raney nickel were almost as active as granular Raney nickel in the second reactor. The pressure drop through the second reactor, however, was reduced 90 percent by the use of these assemblies.

Jan 1, 1962

By David S. Yang, Osamu Taki

The innovative Soil-Cement Mixing Wall Technique, developed independently in Japan, consists of mixing in-place soils with cement grout using multi-axis augers and mixing paddles to construct overlapping soil-cement columns. The applications of overlapped soil-cement columns include cutoff walls for groundwater control and structural diaphragm walls for excavation support. The special features of this technique include water tightness, versatile strength design, and efficient installation in subsurface materials varying from clayey soils to cobbles or soft rocks. Through the introduction of two recent subway projects in Japan, this paper presents the design parameters, construction procedure, quality control and performance of soil-cement wall for excavation support and groundwater control.

Jan 1, 1989

By Roger Best

In the mining industry, where some of the vehicles are larger than a one-story house, tire maintenance cannot be accomplished by the tire shop alone. It takes an army of people to maintain a fleet of 100 trucks that may be transporting gold, iron ore, oil sand, copper or coal from an openpit to a refinery and eventually delivering the product to a customer. Everyone working in and around these mammoth machines has a duty to help with the maintenance of the tires, whether they know it or not. These responsibilities comprise observation and reporting hazards up to and including changing out a tire and recording the information in a tire-tracking program such as TreadStat.

Jan 2, 2010

By Kenneth H. Johnston

The Weber pool in Washington County, Okla. (fig. 1), covers an area extending from 2 miles east and slightly north of Bartlesville, Okla., to a point approximately 2-1P tiles northeast of Dewey, Okla. The pool is a part of the area designated by the Standing Committee on Oil Field Nomenclature, Kansas-Oklahoma Division, Mid-Continent Oil & Gas Association, as the Bartlesville-Dewey field. In the following discussion of the geology, development, and exploitation of the Weber pool, the writers, by means of structure maps, cross sections through various parts of the reservoir, and tabulated development data and production statistics, have recorded salient information on a field that was developed before .1910 in an Area that has been repressured since 1926. The total oil production to January 1, 19.0., from the 2,639 developed acres considered in this report, was approximately 14 million barrels, or a recovery of about 5,3;2 barrels per acre, or 227 barrels per acre-foot. The production of the estimated 18 million barrels of recoverable oil remaining in the Bartlesville sand reservoir will require the initiation of additional secondary-recovery practices on some of the leases and the application of a more systematic repressuring program on others.

Jan 1, 1950