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By R Shaw, R Williamson

Global iron ore demand, sparked by ChinaÆs rapid industrialisation and emergence as the worldÆs newest steel market, has seen iron ore groups investing heavily in production capacity as well as infrastructure. The success of these new projects depends heavily on reliability, competitiveness and quality control in an increasingly demanding trading environment. Furthermore, the iron ore industry continues to improve its competitiveness in mining practices, technology innovation and management processes. The continued fine tuning of these sectors will be critical to the success of the industry in the years ahead, and this mining sector will continue to demand process improvements from their service suppliers to maintain competitiveness. Automation offers a real solution to these demands. A crucial quality control element in mining, beneficiation, stockpiling and shipping stages is ensuring representative samples of ore are taken along each step of the process. When these samples reach the laboratory it is imperative that the sample is representative of the entire stream and that no induced errors occur. Examples of automation start with mechanical primary and secondary samplers in the run-of-mine processes through to sample tower and laboratory crushers, dividers and collectors. Automation is widely used in many forms to provide reliable and repeatable samples for analysis whilst providing a safer working environment. Laboratory automation systems in use today vary from simple linear systems to sophisticated robotic cells. Sample automation in the iron ore industry has resulted in many benefits for both producers and their customers. The most significant benefits have come in the form of higher safety standards whilst reducing sample error, sample handling and sample contamination during collection. These benefits have been further augmented by reliability and repeatability of automating the final sample preparation and analysis stage. Today these benefits are reflected in reduced costs of sampling and improvement in both turnaround time and quality of results, whilst complying with Australian safety and ISO sampling standards.

Jan 1, 2007

The current genesis of pisolites and channel iron deposits (CID) has been defined in a way that presents CID as unique in the world. The published material on detrital pisolites mostly details the West Australian CID; most other global occurrences of iron-rich pisolites would seem to have an in situ genesis. An alternate theory for the origin of the Hamersley CID is suggested, involving an older greensand protore derived from volcanic ash and deposited on a glaciated Hamersley surface. This paper presents the author's observations, sampling and mapping after several years study and exploration for pisolites and CID in WA and in some locations overseas. It is not what one would call scientifically complete, and possibly asks more questions than it answers, but it is presented as a point for discussion.

Jan 1, 2009

By J Pease, P Cameron, D Drinkwater

"In the 1990s metal prices were trending in a long-term decline and the usual cost-cutting exercises were adopted. Cuts to research and development made innovation difficult and the outlook was grim. But necessity is a strong motivator, and these conditions spurred the Mine to Mill movement that optimised across organisational ‘silos’ and utilised new technology tools, innovative software and increased computing power. Many applications of Mine to Mill exploited the fact that comminution is usually the site processing bottleneck and blasting is more efficient at breaking rock than grinding. This approach sought to: understand and characterise rock breakage from mining to the milldevelop models and simulators for blast design, fragmentation, crusher and mill circuitsdevelop tools to measure in real time the particle size distribution of rocks on run-of-mine (ROM) muck piles, at the primary crusher truck dump pocket and on conveyorsensure effective communication across the silos between geologists, blast design engineers, mining engineers and metallurgists.These methods and the technology tools available in the 1990s were widely adopted at numerous sites around the world with significant benefits. Semi-autogenous grinding (SAG) mill throughput increases of 10–20 per cent were common. This was the advance the industry desperately needed. It was low capital cost; it was obvious. It was here to stay.Except, in too many cases, it didn’t. In the minerals price boom of the 2000s Mine to Mill was no longer necessary to ‘survive’, even though it was still good business. Some operations, including some of the early success stories, slipped back to old habits of optimising within organisation silos instead of across them. Fortunately, other operators still embraced Mine to Mill and developed new techniques. Mine to Mill was still successful, but not as widely adopted as we had expected it to be. Now the boom has ended and operations are again under cost pressure. Since these are the same circumstances that created Mine to Mill, it seems time to achieve the wider adoption. Since the 1990s many new or advanced technology tools are now available for Mine to Mill projects: blasthole sensors, new explosives formulations, new blasting techniques and modelling, ore tracking devices, improved image analysis to determine size, texture and colour of coarse ore, grade sensors, whole-stream simulation tools, and even more powerful computing hardware and data analysis software. If we could achieve so much in the 1990s, how much more can we achieve today when we have the same imperative, the same potential and a larger number of high technology tools?Citation:Cameron, P, Drinkwater, D and Pease, J, 2016. The ABC of Mine to Mill and Metal Price Cycles, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 349–358 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

By D. Harrington

Near the close of the nineteenth century electricity was introduced underground, and the mining industry automatically was confronted with another potential source of fatalities and injuries to mine workers. Electricity has become an increasingly vital factor in the production of goal, particularly in recent years, because of the greatly extended mechanization that has taken place underground. The enlarged use of electrical equipment for cutting, loading, and hauling coal unquestionably increased the potentiality of shock and explosion hazards underground. Electricity may be used in coal mines with minimum danger if electric equipment and power-carrying wires are chosen properly and installed and kept protected by proper safeguards; on the other hand, if vigilance is relaxed in the slightest degree accidents may result. Electrical accidents are caused chiefly by direct contact with electrical equipment or power-carrying wires, by ignition of explosive gas or dust, and by fires of electrical origin. Electricity now ranks fourth as a cause of coal-mine fatalities, not including deaths from explosions or fires of electrical origin.

Jan 1, 1936

By Kenneth L. Bickel

During an underground mine fire, the importance of controlling the spread of smoke and toxic gases with suitable ventilation structures has been proven. However, under certain conditions, control of the propagation of the fire itself may be even more critical in insuring a safe mine evacuation. Fire doors offer the means for accomplishing both objectives. In 1978, the Bureau of Mines initiated research to evaluate the state of fire-door technology and develop and test a fire door suitable for large openings (10 by 12 ft or larger) in noncoal underground mines. This report discusses current fire-door technology in the context of the underground mine environment and the design, fabrication, lab testing, and in-mine field testing of a mineworthy fire door. This door has a 1.5-h fire resistance rating and limits temperature rise across the door to 2500 F during the first 30 min of fire exposure.

Jan 1, 1987

By J. A. Scott, K. Moreau, H. Shang

"Trials of automated technology at underground mine sites around the world have reported increased production and the potential for lower energy consumption. Autonomous mining eliminates a range of delays related to operator downtime and travel to the workface and facilitates continuous operation in conditions that are unsafe for workers. Automation also introduces complexities and safety hazards arising from equipment–personnel interactions; automated processes must be isolated from other stope-cycle–related activities such as production drilling, development, loading, and backfilling, poten¬tially requiring changes to the mine design to maintain an efficient and safe operation. This paper reviews and discusses the implementation of automated equipment in deep underground mining operations and the challenges and advantages associated with the technology. ¦ KEYWORDS Automated equipment, Emissions reduction, Energy, Productivity, Sustainability, Technology, Underground mines RÉSUMÉ Des essais de technologies automatisées dans des sites miniers souterrains aux quatre coins du monde ont indiqué une production accrue et la possibilité de réduire la consommation d’énergie. L’exploitation minière autonome élimine tout un éventail de retards liés aux temps d’immobilisation des opérateurs et aux déplacements vers le front de taille, et facilite l’exploitation continue dans des conditions qui s’avèrent peu sécurisées pour les travailleurs. L’automatisation introduit également des complexités et des risques pour la sécurité, qui surviennent en raison des interactions entre l’équipement et le personnel. On recommande d’isoler les procédés automatisés des autres activités liées au cycle des chantiers telles que le forage de production, le développement, le chargement et le remblai, ce qui pourrait entraîner des changements au niveau de la conception de la mine afin de préserver rendement et sécurité dans l’exploitation. Cet article examine et aborde la mise en oeuvre de l’équipement automatisé dans des exploitations minières souterraines profondes, ainsi que les enjeux et les avantages associés à cette technologie. ¦ MOTS CLÉS durabilité, énergie, équipement automatisé, mines souterraines, productivité, réduction des émissions, technologieINTRODUCTION As the mining industry continues to exhaust easily accessible orebodies, the need for efficient, deep (typically below 2,500 m) mine operations increases (Atlas Copco, 2013a); however, the mining process can become economically infeasible at great depths because operation costs drastically increase. This has resulted in investigations into automating mining operations as the industry strives for improved productivity (Schunnesson, Gustafson, & Kumar, 2009) and ways to remove personnel from hazardous work areas."

Jan 1, 2019

By H. Y. Sohn, S. PalDey

"Fine particles of nickel aluminides and Ni4Mo were synthesized by reducing mixtures of, respectively, A1Cl3 + NiC12 and NiC12 + MoC12 vapors with hydrogen. Though thermodynamically favorable, the coreduction of NiC12 and A1Cl3 by H2 to form Ni3Al did not readily happen experimentally. The addition of a small amount of aluminum vapor was needed to initiate the coreduction reaction. The product particles as observed by TEM were very fine but usually agglomerated. The electron diffraction pattern of particles identified NiAl and NiA13 along with Ni3Al and metallic Ni. The content of Ni3Al was maximized at 52 mol% at 1050°C under the partial pressures ofH2, A1Cl3, and NiC12 at 57, 1.4, and 0.5 kPa, respectively. When a mixture of NiC12 + MoC15 was reduced by hydrogen, Ni4Mo particles with some Ni or Mo particles were obtained, the maximum content of Ni4Mo obtained being 93 mol % . The particle size was in the range of 100 to 200 nm. An Ni4Mo coating of 700 nm thickness on an Ni substrate was also prepared.IntroductionThe search for new high-temperature structural materials has stimulated much research on intermetallic compounds. Nickel aluminides have low densities, relatively high melting points, and good high-temperature strength properties. They show an increase, rather than a decrease, in yield strength with increasing temperature (1). Ni4Mo is also of interest as a high-temperature structural material. The major shortcomings of these intermetallics are their inherent brittleness at room temperature when they are in polycrystalline form. For much the same reason, the conventional casting of intermetallics is difficult. Ingot metallurgy and powder metallurgy are two other processing techniques. The first technique is quite energy consuming. In powder metallurgy, the powders of metals and alloys are consolidated in near net shape and then subjected to secondary processing. It would, therefore, be advantageous if intermetallic compounds can be produced in fine powder form from inexpensive raw materials, using less energy."

Jan 1, 1998

By R. Mensah-Biney

The adsorption of gold-thiourea complex onto a cation exchange resin, Amberlite 252, has been evaluated in a batch stirred reactor. The observed non equilibrium saturation capacity was 3.20 meg Au/g dry resin (620 kg/t) whereas the equilibrium ion exchange capacity was only 0.53 meq/g (103 kg/t). The enthalpy of adsorption was 4 -25 kJ/mole under equilibrium conditions and increased to 20-200 kJ/mole under non equilibrium conditions. Under non equilibrium conditions, the adsorption capacity of the resin decreased with increasing temperature and increasing thiourea concentration and increased with increasing gold concentration. This dependence of adsorption capacity on thiourea concentration and temperature may be a useful tool for elution of gold from the loaded resin. Scanning electron microscopy revealed evidence of deposition of elemental gold on the loaded resin under non equilibrium conditions. The proposed mechanism for "adsorption" of gold-thiourea complex onto this cation exchange resin consists of an ion exchange reaction followed by a reduction of the exchanged gold complex to elemental gold on the surface of the resin.

Jan 1, 1997

By R. E. Lund

The design, operation, and performance of an integrated pilot plant for recovering zinc and copper from a complex sulfide ore are described. Metallurgical processing comprised selective sulfate roasting in a fluid bed, leaching in a weak sulfuring acid solution, recovering copper by cementation with scrap iron, air oxidation to remove soluble iron, more-or-less conventional purification for removal of impurities deleterious to zinc electrolysis, recovering zinc by electrolyzing solutions, and recycling spent electrolyte to the sulfating roaster. The effects of several feed preparation and roasting variables on the sulfation response of zinc, copper, and iron are set forth, together with the electrolyzing characteristics of the zinc solutions.

Jan 1, 1962

Major activities of the Bureau of Mines Explosives Research Center during fiscal year 1965 (July 1, 1964, to June 30, 1965) are reviewed briefly. Part 1 summarizes significant accomplishments of the projects that were active during the report period. Part 2 presents short abstracts of the publications that appeared in the Bureau series and in other media during fiscal year 1965. Publications issued after June 30, 1965 are noted where pertinent in footnotes but are not abstracted. ACKNOWLEDGMENTS The Bureau of Mines gratefully acknowledges the support given through cooperative agreements by the following organizations to investigations con¬ducted by the Explosives Research Center during fiscal year 1965: Dow Chemical Company Manufacturing Chemists' Association Monsanto Chemical Company The Sulphur Institute

Jan 1, 1966

By C. B. Barmore, B. W. Gandrud, B. M. Bird

"The Bradford mine of the Alabama By-Products Corporation is located in the Warrior coal field of Alabama, in the northern part of Jefferson County, about 25 miles north of Birmingham. The coal mined from the Black Creek bed at this point is not considered to be ideal for coke making by itself but because of its exceptionally low ash content is mixed with the higher-ash coking coals from other beds of the district to control the ash content of coking mixtures. Further reasons for using this coal only as a diluent of the higher-ash opals are that the thinness of the bed renders the production costs relatively high and the reserves are somewhat limited.This paper, which is the fourth of a series on the washability of Alabama coals, Like its predecessors dealing with the Mary Lee beds and the Clark bed,6 contains screen-sizing and float-and-sink tests of a representative sample of the raw coal, and flakiness tests showing the proportions of flaky particles in certain selected sizes. However, inasmuch as the float-and-sink tests of the coarse sizes showed excellent liberation of coal from impurities, crushing tests have not been considered necessary.The data on which this report is based have been obtained in connection with an exhaustive study of coal preparation in Alabama now being conducted by the U. S. Bureau of Mines and the University of Alabama with the cooperation of the different coal operators. As the work progresses other papers will follow containing further data on Alabama coals and giving results obtained in preparing these coals by various methods."

Apr 1, 1931

In practice a sampling solution is a compromise of many requirements: the sample should be representative; the sampling system should also be reliable, less than 95 per cent availability restricts the use of the assayed sample for process control purposes; no sample is the worst sample, and investment costs and installation space/layout are frequently a restriction. For instance, online X-ray analysers for process control introduce a delimitation error by the nature of X-ray physics. Thus only in special cases a relative accuracy better than three per cent relative, as one standard deviation, is achieved. A sampling system for process control needs not to be, as representative, for so many sample properties, as one for composite laboratory analysis samples. Sampling system maintenance is also an important issue. There are many sampling systems in the industry which have been difficult to maintain and are in disuse for lack of resources or incentives to keep them running. Pierre Gy developed the most generally accepted sampling theory. One of the main principles is that all particles in a one-dimensional process stream should have equal chances of being included into the sample. A correctly designed and operated transversing cutter comes close to this goal but has limitations in temporal representativity. For slurries an acceptable solution in many cases is to use a fixed vertical cutter(s) in a position where the slurry is well-mixed by turbulence and other means. For online analysis, reliability problems are mostly related to faulty design or installation of the piping system to the analyser. Properties of material processed, process flow sheet and piping details before and after the sampler have to be taken into account when deciding on which sampling arrangement is appropriate. Guidelines and some solutions to these issues are presented in this paper.

Mar 1, 2010

The paper point out the way whereby the Canadian gobernment regulates and motivates mineral development. In this sense, its important the role of Gobernment policy in the development of the industry to its a stage. The progress of industry is due to a favorauble political climate which created an atmosphere of trust that has atracted foreing investment. Therefore, Canada's position owes much to sound legislation that recognizes the high element of risk in exploration and development and also the exhaustibility of mineral deposits.

Nov 20, 1969

By C. Díaz

Roast-reduction smelting (RRS) of nickel concentrate, combined with flash smelting of copper concentrate, was one of the process options that Inco considered as a means of meeting its 1994 sulfur dioxide abatement target at its Copper Cliff operations. RRS involves deep roasting the nickel concentrate in fluid bed roasters. The roaster off-gas is heated in a sulfuric acid plant, and the low sulfur calcine is reduction smelted with coke in an electric furnace to yield a sulfur-deficient matte. The latter material is converted to Bessemer matte in Peirce-Smith converters, with minimal evolution of sulfur dioxide, and the converter slag is reverted to the electric furnace. Excellent nickel and cobalt recoveries are obtained. This paper discusses the development of RRS, including extensive commercial scale testing at Inco's Thompson Smelter, and its key operating parameters.

Jan 1, 1993

By D. B. Stewart

In the past few years, much effort has been spent in elucidating the impact of diesel engines on the mine environment. This paper summarizes diesel fundamentals , exhaust emissions and typical tailpipe concentrations. Mine sampling results and an evaluation of exhaust treatment systems are discussed. A review of changes in pollutant concentrations between the tailpipe and the mine exit is made and suggestions are given to reduce operator exposure to diesel contaminants.

Jan 1, 1978

Declines for both access and rock haulage are replacing shafts for mining relatively shallow deposits of down to 1000 m below surface. Where the orebody does not outcrop and where surface access may be restricted, it is often necessary to drive long dead end headings before a connection can be made back to surface and a ventilation circuit created. In hot tropical areas and where large diesel powered equipment is used for mining, heat may also be a problem at these relatively shallow depths. The normal design criteria based on statutory limits and good practice used to evaluate ventilation and cooling requirements in terms of air velocity, dust, gases, diesel exhaust dilution, re-entry after blasting and heat stress are described in this paper. These are then used to design and cost alternative auxiliary ventilation systems that include leakage based on general fan performance curves and typical duct systems. The implications of the current European Community recommendations regarding nitrous fumes are also briefly considered. The actual problem relates to a 2100 m long decline that may have to be extended to 3000 m long without a connection to surface or through ventilation and is located in a hot tropical area where the surface wet bulb temperatures may exceed 25¦C for more than a third of the summer period. Once the preliminary ventilation design is completed, the auxiliary ventilation system can be modelled and simulations undertaken that incorporate heat and moisture transfer routines with the objective of determining the cooling load and amount of refrigeration required. Cognisance is taken of cyclic diesel operations and the thermal flywheel effect of the surrounding rock on the wet and dry bulb temperatures resulting from these operations.A suitable modular cooling system located at the portal is described and optimised with capital and operating costs of both the ventilation and cooling systems provided.

Jan 1, 2005

By R. V. Higgins

The, large volumes of low A. P. I. gravity oil that will remain in many shallow fields of California when such oils no longer can be recovered profitably by pumping are important potential sources of oil when ways and means are found to remove them from the reservoir sands. Estimated ultimate oil recoveries in many of the "low-gravity fields" of the San Joaquin Valley in California indicate that less than 25 percent (on the average) of the original oil will be recovered. These oils have viscosities of 1,000 or more centipoises at reservoir temperatures and, because of their high viscosity and low intensity of the reservoir pressure, the quantities that will be retained in the sands ultimately are so large and their recovery is such a challenge to petroleum engineers that the Bureau of Mines has made the study of their possible recovery one of its major projects. The fact that a slight increase of temperature materially reduces the viscosity of low A. P. I. gravity oils has 'prompted the use of various means for increasing the temperature of the oil in the reservoir sands and hence the rate of flow and Completeness of recovery of the oil. Hot oil, hot water, heated air, and natural gas, steam, super-heated steam, and the products of combustion have been circulated in wells to raise the temperature of the oil it the sands; electric heaters have been installed in wells, and butane and air have been intermittently exploded and the flames propagated through the tubing to the "pay" zones. None of the methods, however, have been entirely satisfactory for the recovery of large quantities of oil.

Jan 1, 1949

By W. A. Jones

Purpose of Paper Geophysics is a highly developed science which has found a wide use in industry. Perhaps the most spectacular application has been in the field of oil exploration. It has been estimated that, up to the end of 1939, geophysics was responsible for the discovery of five billion barrels of oil. In 1944, the sum o $40,000,000 was expended for geophysical work in the search for new oil deposits. Although the metal mining industry has so far made comparatively little use of the science, it is becoming increasingly common for the exploration engineer or geologist to be required to co-operate with the geophysicist. Many papers dealing with applied geophysics have been published but in most of them advanced training in physics and mathematics on the part of the reader has been assumed. It is difficult for the average engineer to obtain a ready understanding of the equipment, field procedure, and scope and limitations of the science from the literature. The present paper attempts to describe briefly and in simple terms the principles underlying magnetic, self-potential, and electrical resistivity methods and their application to a field problem. Introduction Geophysics is concerned with the study of gravity, magnetism, natural earth currents, earthquakes, vulcanism, and many other natural phenomena. The methods, originally devised for the measurement, for scientific purposes, of the forces associated with such phenomena have been adapted to the search for buried deposits of economic value. If the body sought has large dimensions and distinctive physical properties, geophysical measurements may reveal associated, and in some cases quite characteristic, anomalous features. However, in many instances the mass cannot be indicated directly but has a common association with geological features which can be defined by physical measurements. Although such surveys cannot specifically identify oil, metalliferous minerals, or other commercially valuable substances, it is possible to delineate anomalous sub-surface physical features which, with the help of geological information, can be assessed as possible or probable indications of the body or structure sought. The nature and extent of the material causing an anomaly, and its economic importance, can only be determined by further exploration, such as drilling.

Jan 1, 1947

By R. W. Geehan

The Yellow Pine zinc-lead mine, situated about 3-1/2 miles northwest of Goodsprings, Clark County, Nev., was explored by core drilling during the fall of 1942 and the summer and fall of 1944 by the Bureau of Mines in cooperation with the Federal Geological Survey. The Yellow Pine district was located in 1855. The original claims covering the Yellow Pine mine were located in the following years: Rover, 1892; Hilo, 1897; Bybee, 1900; Radio and Como, 1906. The mine was operated by the Yellow Pine Mining Co. from 1906 to 1929. This company was dissolved in 1935. At a later date, S. E. Yount and the Security First National Bank of Los Angeles, Calif., acquired ownership of the mine. Since 1939, the mine has been operated in a small way by leasers. Production has been at least 175,000 tons averaging about 10 percent lead and 25 percent zinc, with a gross yield of $5,785,174. Virtually all ore produced by this mine consisted chiefly of oxidized zinc and lead minerals and came from long, pipelike shoots in the 100-foot thick Yellow Pine limestone. Ore shoots are sharply defined; elsewhere, the limestone is nearly barren. Numerous faults cut the mine into blocks. Ore is now mined in an open stope, but in the past, large tonnages wore mined in stopes by square-set methods. Ore produced recently was shipped direct to smelters unprocessed; in the past, it was milled by gravity and produced separate lead and zinc concentrates.

Jan 1, 1949

By George H. Willis

In the second half of the nineteenth century, bimetallism progressively replaced by gold standard. After World War I and 1931-33 depression, gold mainly reserved for official international transactions and internal use restricted. Changes since 1971 have shrunk official international use of gold. International payments deficits and surpluses now financed by private and official credit, rarely by gold. Historical review covers evolution of: (1) internal and external private use, (2) internal official use, (3) external official use, (4) role in IMF and (5) use as unit of account.

Jan 1, 1978