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By M S. Tuohy

Since the independent review of fatal accidents in the mining industry carried out by Dr Sean Brady (the ‘Brady Review’), High Reliability Organisations (HROs) and their operating principles have been discussed across the Queensland mining sector. HROs are organisations said to consistently avoid serious failures, reliably delivering their organisational objectives despite operating in environments characterised by high levels of inherent risk and/or operational complexity. HRO concepts have previously found application in other similarly hazardous industries to mining. However, as Hopkins (2009) pointed out, HROs ‘are very elusive creatures that inhabit the realm of theory more than the real world’. The Queensland Resources Council (QRC) with support from the Commissioner for Resources Safety and Health initiated a review of how HRO principles can be translated to the mining industry. The review was conducted by Noetic, an Australian management consulting company that specialises in hazardous industries, including mining and metals, and has prior experience applying HRO theory.

May 5, 2022

By T. Bajpayee, L. Prosser, A. Iannacchione

Reducing the number of roof fall injuries is a goal of the NIOSH mine safety research program. Central to this effort is the development of assessment techniques that will help to identify the nature of the risks associated with working under potentially hazardous roof conditions. This paper discusses a method to determine the roof fall risk using a qualitative risk analysis technique. The ability to determine roof fall risk has been a long-standing goal of safety professionals and can provide the kind of information, needed by on-site personnel responsible for worker safety, to mitigate roof fall injuries.

Jan 1, 2007

By D. S. Saxena, Jack K. Tuttle

Lack of understanding of useful applications of explosives on construction work stem primarily from the fact that explosion is commonly associated with destruction. On rock excavation and other construction works a certain quantity of explosive is harnessed to perform useful work at the source e.g. blasts to disintegrate rock. Development in rock blasting techniques, including the use of multiple-row blasting with short delay ignition, have made it impossible to excavate rocks close to or below buildings even in closely built-up areas. To permit the use of explosives on construction projects, in ways that will not damage existing structures, guidelines have been developed from careful measurements of intensity of ground vibrations. Accurate electronic instruments are now available for doing this. PLANNING AND CONTROL Blasting operations must be carefully planned and carried out to avoid discomfort to persons or damage to property. This increase in the use of rock blasting in city areas alone has led to a number of problems due to ground vibrations, air shock waves, and the psychological effect of noise. While the latter seldom if ever causes damage, it does create irritation and discomfort to persons living or working near the blasting sites. A result of this is a steady increase in the number of complaints in respect of damage to houses and other premises. Many such complaints are genuine and damage may undoubtedly be caused when incorrect blasting techniques are used.

Jan 1, 1997

Ceremonies for the induction of four mining industry pioneers into the National Mining Hall of Fame will be held Saturday, Sept.9, 2006 at the Museum Convention Center in Leadville, CO. The four inductees are Earl H. Beistline (1916 to present), R.A.F. Penrose (1863-1931), Robert M. Reininger (1912-2006) and John Stanton (1830-1906). The inductions will bring to 193 the number of mining “greats” whose engraved photographs and biographical sketches are installed in the National Mining Hall of Fame.

Jan 1, 2006

By M. K. Seguin

The study described in this paper is first centered on the determination of the physical properties (gravimetric, magnetic, electrical, and electromagnetic) o f metamorphosed iron ores of the Carol Lake-Labrador City District. Different geophysical surveys available in the Carol Lake-Wabush area were interpreted quantitatively and the dimensions, attitude, and tonnage of the ore bodies investigated were determined. A geophysical-statistical study was undertaken which permitted the determination of the grade of iron, magnetite, and, subsequently, specularite in the ore bodies. A discussion of the theory and logical progression of the study and the application of the results to actual geophysical data is presented. The conclusions, which are of real significance from the economic standpoint, may be predicted from the data obtained from geophysical surveys before any diamond drilling is undertaken. An integrated interpretation of this type is useful in planning future exploration work and selecting the most favorable geological structures. It also serves as a guide to minimize and determine tonnage drilling patterns. The general conclusion that a restricted range of residual gravity and magnetic anomalies are a key to exploration is valid. Indeed large depths to the top of deposits are absent since all the ore bodies are overturned synclinal structures with tops located close to the surface. Certain irregular geometries do occur but they are not common and the alignment of the iron ore bodies is sub parallel so that magnetic anomalies are evenly reduced in the earth's magnetic field vector.

Jan 1, 1975

By Pakalnis Rimas, Lyndon Clark, Tom Brady

A major focus of ground control research presently being conducted by the Spokane Research Laboratory of the National Institute for Occupational Safety and Health (NIOSH) is to incorporate data on weak rock masses into existing design relationships, with an emphasis on updating the span design curve for manned entries and the overbreak curve for longhole entries. Both curves were originally developed at the University of British Columbia, Vancouver, BC. The original database has been augmented by information from mines throughout the United States, Canada, Australia, and Europe. The common factor in all these mines is the presence of a weak back and/or walls. In most cases, the ore zone is the weakest rock unit and must be stabilized so that the mineral-bearing rock can be extracted safety. The current NIOSH research attempts to provide rock mechanics tools to assist a mine operator in making economic decisions that will also ensure a safe working environment. This paper documents the Nevada database with a special emphasis on Nevada underground gold mines.

By Lars Arne Granlund

Due to the coarse structure of mining explosives, one has to model a finite reaction zone,contrary to C-J calculations, describing their detonations, i.e they become dependent of diameter and confinement, An effort within the DYNO group has been to investigate if the DSD theory ( originally developed by Bdzil, Stewart / Los Alamos ) can be used to describe major groups of civil explosives.The groups of explosives tested are dynamite, anfo, aluminised emulsion, heavy anfo and straight emulsions.

Jan 1, 1995

By Ricardo Burdisso, Rahul Kadam, Kyle Schwartz, Marty Johnson

Occupational exposure to hand transmitted vibration (HTV) arises from the hand held powered tools extensively used in the mining and construction industry such as rock drills, chipping hammers, chain saws etc. Regular exposure to HTV is the major cause of a range of permanent injuries to human hands and arms which are commonly referred to as hand-arm vibration syndrome (HAVS). In addition to this, the percussive tools generate overall sound power levels in excess of 110dBA in most cases. Such a high sound power level greatly exceeds the maximum permissible exposure limit (PEL) of organizations such as National Institute for Occupational Safety and Health (NIOSH) and the Occupational Safety and Health Administration (OSHA). Long term occupational exposure to this noise has been diagnosed as the main reason for permanent hearing loss in the operators. It is therefore important to develop an understanding of the mechanisms which lead to these high vibration and sound levels and in order to do this a detailed computational model of a pneumatic chipping hammer has been made. This paper presents a nonlinear computational model of a pneumatic chipping hammer. In order to better understand the dynamics of the chipping hammer, the hammer was subdivided into components that are shown in figure 1 (a) (based on a chipping hammer manufactured by Atlas-Copco). The hammer mainly consisted of a center body, a moving piston and a chisel. Compressed air is used to drive the piston inside of a cylinder and on the downward stroke this piston impacts the chisel to create the hammer effect. The machine has one pneumatic valve and this valve regulates the air supply either to the upper chamber or to the lower chamber. The valve changes according to the relative pressures in the two chambers and the supply pressure. There are also twelve different exhaust ports at two positions along the cylinder labeled upper ports and lower ports. As the piston moves the ports can be closed or open (allowing exhaust). Fundamentally, the computational model was made up of two different sub-models, a fluid model and a structural dynamic model as shown in Figure 3 (a) and (b) respectively. The first sub-model takes into consideration the fluid dynamics of the machine since the hammer is driven by compressed air. Equations for the mass flow rate though bleed orifices (assuming an isentropic process) 1 is used to determine the mass flow into and out of the upper and lower chambers. From this the pressures in the two chambers and consequently the forcing on the piston can be calculated. The second sub-model deals with modeling the structural [ ]

Jan 6, 2006

By A. Vien, B. C. Flintoff, R. P. Edwards

"A major thrust in industrial automation over the past few years has been the exploration and incorporation of higher level (supervisory and optimizing) control strategies aimed at more fully exploiting the existing control system infrastructure. There is little doubt that this is worthwhile pursuit, however, one must not lose sight of the maintenance and development requirements of the basic control system. Statistics on loop performance indicate that this too is an area of considerable potential. In this paper the authors look at some of the less elegant, but arguably equally important issues in mineral processing plant control. The focus is on controller structures, loop tuning, sampling, filtering, and some of the other principal components of the regulatory control foundations. In many cases significant improvements in control performance can be achieved by getting back to the basics.IntroductionEvery modem concentrator has a state-of-the-art computer control system in place. Several of these are contemplating installing, or have installed, advanced control systems, such as expert systems, but the foundation of their control system remains the PI controller. Although the authors are not aware of any survey or published information for the mineral processing industry, it is reasonable to assume that it would be similar to the pulp and paper industry. ""The average [pulp] mill has some 2000 control loops of which 97% use PI control. This means that PID, dead time compensation, adaptive controllers, specialized algorithms, ... , constitute only 3% of the installed base."" (Bialkowski [1992]).Bialkowski [1992] also stated that ""If you have been keeping score, only 20% of the loops surveyed actually decrease variability in automatic over manual mode of operation, in the short term."" He attributed the problems to: poor tuning (30% of all loops), control valve problems (30% of all loops) and process problems (20% of all loops). There appear to be a serious need to go back to basics and review the existing control system."

Jan 1, 1998

By T. M. Ruff

A prototype mucking machine designed to operate in narrow-vein stopes was developed by Foster- Miller, Inc., Waltham, MA, under contract with the U.S. Bureau of Mines. The machine, called a compact loader-trammer, or minimucker, was designed to replace slusher muckers in narrow-vein underground mines. The minimucker is a six-wheel-drive, skid-steered, load-haul-dump (LHD) machine that loads muck at the front with a novel slide-bucket system and ejects it out the rear so that the machine does not have to be turned around. To correct deficiencies of the tether-remote-control system, a computer-based, radio-remote-control system was retrofitted to the minimucker. Initial tests indicated a need to assist the operator in guiding the machine in narrow stopes. An automatic guidance system that used ultrasonic ranging sensors and a wall-following algorithm was installed. Additional tests in a simulated test stope showed that these changes improved the operation of the minimucker. The design and functions of the minimucker and its computer-based, remote-control system are reviewed, and an ultrasonic-sensor-based guidance system is described.

Jan 1, 1992

By P. H. Rodriguez

The aquatic hazard classification system of the OECD and EU requires that sparingly soluble metal substances (SSMS) be tested using the OECD Dissolution/Transformation protocol in order to quantify the release of the ecotoxicological relevant species (dissolved ions). The SSMS category contains massive forms of metals, which due to their low solubility and slow transformation characteristics are a special case. The main factors that produce the release of metal into solution are exposed surface loading, pH, and stirring rate. The classification system at present prefers the use of mass loading as opposed to surface loading, in which case the amount of metal released will primarily be a function of the pH, and mass loading. Within the framework of the European Copper Voluntary Risk Assessment, coordinated by the European Copper Institute, we have proposed and developed a methodological procedure in which we demonstrate that surface area is an intrinsic property of a SSMS and we link the exposed surface loading to the toxicity reference value in order to obtain an aquatic hazard classification for massive metals. As example, the aquatic hazard classification for copper massive will be discussed. This approach is recommended for metal massives and metal powders.

Jan 1, 2007

Mr K.R. Beard was born on 19th December, 1958. He attended Marist Brothers College, Observatory, and Marist Brothers College, Linmeyer. He was awarded a bursary by SEIFSA (Steel and Engineering Industries Federation of South Africa) and gained the degree of B.Sc. Eng. metallurgy at the University of the Witwatersrand in 1982. He is a member of the Engineers' Society of South Africa. Mr G.A. Brown was born on 27th June, 1934, and matriculated at St John's College. He obtained the degrees of RSc. Eng. (Met.) at the University of the Witwatersrand in 1957, and M. Met. at Sheffield University in 1959. He is a member of the Institution of Mining and Metallurgy (UK) and the Society of Mining Engineers (USA). Or LA. Cramer was born in the USA and, having received a B.Sc. degree in metallurgical engineering from the Colorado School of Mines, he emigrated to South Africa in 1971. He enrolled as a graduate student at the University of Natal and successfully completed both an M.Sc. and a Ph.D. degree in chemical engineering.

Jan 1, 1989

By S. F. Fu

The Charkhan Salt Lake area of the Chaidamu Basin in West China is characterized by soft super-saline soils with very high contents of soluble salts. From the engineering point of view, these saline soils are saturated, liquid-plastic and moderately to highly compressible lean silty clay and clayey silt. In the natural state, their allowable bearing capacity is only 60-80 kPa. As to the saturated lean silty clay, liquifaction in case of an earthquake of intensity 7 on the Modified Mercalli scale is considered likely. In order to improve the geotechnicai properties of the saline soils, stone colomn stabilization by means of vibroflotation was performed. As the geotechnicai properties of the soils are closely linked with the amount and composition of the soluble salt content, saline water with chemical content similar to that of the saline soils was used as flush fluid in the course of hole-making and column-forming, with a view to keeping unaltered the amount and composition of the salts in the soils and thereby precluding reduction in or loss of their strength. Systematic monitoring on the behavior of the foundation soils before and after the treatment and comparison of the numerical data thus acquired have shown good technical results, testifying to the effectiveness of stabilization of soft superealine soils by vibroflotation. As a result of the treatment, the allowable bearing capacity was increased one to two fold, accompanied by elimination of the liquefaction potential.

Jan 1, 2010

By John Haviland, Richard E. Danell

"BHP Australia Coat Pty Ltd (BHPAC) operates seven large open pit coal mines in the Bowen Basin ofCentral Queensland, Australia. These mines have operated for periods ranging from 16 to 37 years. All of these mines have dipping seams to varying degrees and are facing increasing overburden removal in an effort to maintain production. To ensure the economic viability of the operations, this increased level of overburden removal must ah.0 be conducted at lower unit costs."

Jan 1, 1995

By Juliana Gutiérrez-Paredes

Keywords: Slag, chromium oxide, recovery, stainless steel Experimental and theoretical work was performed to estimate the effect of slag basicity and amount of reducing agents on the reduction of chromium oxide from the slag which interacted with molten steel at 1600°C. The slag system contained CaO, MgO, SiO2, CaF2 and Cr2O3 together with Fe-alloys (Fe-Si and Fe-Si-Mg). The CaF2 and MgO contents in the slags were 10 mass % each; Cr2O3 was 25%. The amount of the ferroalloys ranged from 12.5 to 50 g per 100 g of slag. The (CaO+MgO)/SiO2 ratio was held at 1 and 2. The Cr yield was determined using both Fe-alloys as reducing agents. Some estimations were made to determine the theoretical effect of temperature, slag basicity, (CaO+MgO)/SiO2, and amount of reducing agents in the slag on the chromium recovery. The FACT (Facility for the Analysis of Chemical Thermodynamics) computational package is used to determine the equilibrium between the slag and molten steel.

Jan 1, 2005

By Homer S. Frankhouser

Materials may be dredged, processed, stored and loaded for shipment at a single site in water depths ranging from 250 to 1200 ft. Solution mining may also be accomplished in deep sea situations. And, open air subsea mines with direct surface access may be developed and worked under the ocean floor. These concepts for deep sea mining are the results of extensive testing of individual components of the proposed systems by Dravo Ocean Structures, Inc., a subsidiary of Dravo Corp. A basic structure in these systems is the articulated platform. The platform consists of a gravity- type base and a buoyant cylindrical column which is constructed at an onshore location, towed to the offshore site and installed in a matter of days without use of heavy equipment. The base is also buoyant for towing purposes. This allows for gradual flooding to the point of negative buoyancy for positioning and anchoring to the ocean floor.

Jan 1, 1971

The United States continued to depend on imported bauxite during 1995. Domestic bauxite mine production remained at about the same level as in 1994. It amounted to less than 1% of total world production. All of it was used for nonmetallurgical products, such as abrasives, chemicals, proppants and refractories. Metallurgical grade bauxite was imported from 12 countries. Principal suppliers for this 10 Mt (11.1 million st) of ore were Guinea (39%), Jamaica (35%), Brazil (17%) and Guyana (8%). The average value of imports, c.i.f. US ports, was $31/t ($28/st). Calcined refractory-grade bauxite imports totaled235 kt (259,000 st). It had an average value of $112/t($102/st) c.i.f. US ports. China supplied 61%, Guyana30%, Hong Kong 4% and France 3%. Imports of other grades of calcined bauxite, primarily for the abrasives market, totaled 259 kt (286,000 st).They were supplied by China (59%), Greece (20%), Brazil (14%) and Australia (6%). The average value was$74/t ($67/st) c.i.f. US ports.

Jan 1, 1996

By Rodolfo Espinosa Gómez

"Industrias Peñoles, S.A. de C.V. – Mining Division, has initiated in the last ten years, six Mining Operations (Bismark, Tizapa, Ciénega, La Herradura, Rey de Plata, and Francisco I. Madero) and it has expanded several of their existing Operations (Sabinas, Fresnillo, Tizapa, Ciénega) one or more times.This work aims to share the experiences learned on this growing process. Some of these lessons are: 1) Project leaders must have a leadership that fosters good communication and team work; and this leadership style must come from top management. 2) A good communication must exist between the personnel from Engineering, Construction, and Operation. Also, this good communication must come from top management. 3) Starting the project with a solid Engineering Study. 4) Do not misunderstand cost with cost/benefit; always look at the cost/benefit. 5) Selecting good Contractors and good Suppliers. 6) Good training before the project commissioning is essential to reduce the learning curve period, this is even more important in areas where local people do not have any background in mining activities. 7) Recognizing that any project has a learning curve and it must be reflected on the production budget. 8) Avoid an over optimistic Mine preparation time schedule.BACKGROUNDIndustrias Peñoles S.A. de C.V.The mission of Industrias Peñoles, S.A. de C.V. (Peñoles) is to add value to non-renewable natural resources in a sustainable manner. Peñoles seeks to build long-term shareholder value; provide their customers with the highest quality products and services; maintain productive longterm relationship with their suppliers; develop and promote the capabilities of their personnel; foster mutually beneficial relationship with the communities in which it operates, and preserve the environment.Peñoles was established on 1887. It is a Mining Group with integrated Mining, Smelting and Refining operations of non-ferrous metals, and also produces inorganic chemistry materials. Peñoles is the main World producer of refined silver, metal bismuth, and sodium sulphate; Latin American leader in the production of refined gold, lead, and zinc.The Mining Group is made-up of nine mining operations producing concentrates with high gold, silver, lead, zinc, and copper contents. It produced in 2002, 365,900 ounces of gold; 52.7 million ounces of silver; 86,820 tonnes of lead; 266,000 tonnes of zinc, 11,840 tonnes of copper; with a total values of 3,780.6 million of Mexican pesos (~ $ 378.0 million U.S. Dollars)."

Jan 1, 2004

By A. Griffiths, G. Vickell

"INTRODUCTIONA successful cyanide destruction process has to ensure environmental compliance at reasonable cost. That this is possible with hydrogen peroxide is shown by the fact that over twenty gold mines either already use H2O2 or intend to start using it within the next few months. About half of these mines are in Canada.This growth is remarkable, considering that the first treatment plant to use H2O2 for detoxifying cyanide was commissioned less than five years ago at Ok Tedi, in Papua New Guinea.Hydrogen peroxide is being applied to a wide range of situations, including:Treatment of CIP pulps; examples: Ok Tedi, PNG; Hope Brook, Nfld.Treatment of barren bleeds and filtrates; examples: Nickel Plate, B.C.; Puffy Lake, Man.Treatment of tailings pond discharge; examples: Detour Lake, Ont., Page Williams, Ont.Treatment of excess heap leach solution; examples: Hope Brook, Nfld; Gordex, NS.Treatment of barren heaps after heap leaching; examples: Alhambra, NV; Wharf Resources, S.D.Treatment of pond reclaim water to prevent either ""preg-robbing"" or depression of gold-bearing pyrite in a flotation step; example: Getchell, NV.Treatment of backfill to prevent possible groundwater contamination; example Hope Brook, Nfld.Treatment of tailings ponds to prevent bird kills; example: Paradise Peak, NV.""Emergency"" units to deal with unusual events such as freak storms or dam failures."

Jan 1, 1989

By S L. Birch, M D. Raven

X-ray diffraction (XRD) is a well-recognised, invaluable tool to provide detailed mineralogical analysis on a wide range of applications. However, despite the wide use of XRD in many industries, there are currently few recognised standard methods for quantitative XRD analysis and none for the analysis of iron ore materials. An initial step towards preparing a standard method for XRD analysis of iron ores was to assess the current level of precision achievable by practitioners of the technique by organising an international round robin. Six Australian chemically certified iron ore reference materials were distributed to over 100 international participants. A summary of over 120 data sets from more than 80 participants is presented. Results show that a bewildering array of techniques for sample preparation, data collection, phase identification and quantification were used. The reported values for the main components (ie hematite, goethite, quartz and amorphous content) show not only extensive variability between participants but also within participants’ results for those who submitted multiple data sets. The disappointing low level of precision exhibited for a relatively simple mineral phase system indicates a strong requirement for development of a standardised procedure.CITATION:Raven, M D and Birch, S L, 2017. Summary of results of an international X-ray diffraction round robin for mineralogical analysis of iron ores, in Proceedings Iron Ore 2017, pp 599–604 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017