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By B. D. Thompson

Many mines adopt necessarily conservative backfilling strategies due to a lack of understanding of their backfill behaviour. In the past five years, extensive instrumentation campaigns have focused on measuring in-situ cemented paste backfill behaviour. These tests have resulted in optimised backfilling efficiency through elimination or reduction of cure periods where; i) controls on backfill behaviour are understood, and ii) barricade pressures are demonstrated to be within a safe range using routine monitoring as a required QA/QC procedure. Recently, this work has been extended to consider hydraulic backfill operations. Two stopes have been instrumented at Vale?s Coleman and Garson Ramp mines. The instrumentation and deployment methods are discussed, and representative total earth pressure, pore pressure, and temperature data are presented. In one case, pressures in the stope are relatively low as drainage causes strength gain in the fill and so pressures are arched. In a second example, again, drainage causes strength gain in the fill, but increasing temperatures correlate with pressure increases even during downtimes in filling. These pressure increases are thought to be caused by thermal expansion of the backfill in confined locations. Generally, the instrumentation approach has proven successful in measuring hydraulic backfill behaviour and offers good potential for incorporation into a procedure to safely maximise backfilling efficiency through routine barricade pressure monitoring, when combined with safeguards to ensure adequate fill drainage.

Aug 1, 2013

By J. Grant Spratt

THE Turner Valley gas-field, situated some thirty miles southwest of Calgary, Alberta, has been the topic of much discussion, particularly from a geological viewpoint. Several papers (1, 2, 3, 4, and 7) dealing with the structural and stratigraphical geology have already been published and are available for reference(l). In this article, the geological conditions will be treated only as they directly refer to the crude-oil prospects along the west flank of the anticline. HISTORY During the past twelve years, Turner Valley has been known mainly as a field which has produced a high-gravity naphtha from relatively large quantities of gas. For about ten years prior to the discovery of this naphtha-bearing gas, which is produced within the upper 450 feet of a dolomitic limestone of Carboniferous age, a minor production of light crude-oil was obtained from overlying sands of Cretaceous age. Up to June 1st of the present year, the field had produced 9,473,582 barrels of naphtha from approximately 829,000,000 M.c.f. of gas. For the past four years, the total daily production of 80 to 90 wells has averaged about 3,200 barrels of naphtha from 250,000 M.c.f. of gas. This is an average of 13 barrels per million cubic feet. The naphtha is extracted from the gas by ordinary gas-oil separators and absorption plants. After the naphtha has been recovered, about ten per cent of the gas is marketed for fuel to supply the cities of Calgary and lethbridge and intermediate cowns. The remaining ninety per cent is burned to the atmosphere, with the exception of some four to five million cubic feet per day which the Calgary Gas Company score in the depleted Bow Island gas-field.

Jan 1, 1936

By Jakob Janzen

This paper demonstrates that the introduction of a Battery Energy Storage System (BESS) into an isolated diesel generator based grid has the potential to reduce the electricity cost and deliver a good return on investment. Energy storage also allows for increased renewable energy penetration, into the isolated grid, that further reduces the electricity cost. The isolated power system studied includes several diesel generators of different sizes. The typical operating pattern is for the generators to be run at 80% to 85% of their power rating to deal with load fluctuations. Operating the diesel generators near their full power rating, however, improves their efficiency, in this case, while the frequency and load control can be carried out by the BESS. Operating the diesel generators near their full power rating reduces the number of generators which need to be operating to support a given load. As a result, the improved efficiency of the diesel generators and reduced maintenance cost, for operating fewer machines, are the reason for the savings.

Aug 1, 2013

"With the plethora of cable bolts on the market, geotechnical engineers can be baffled by the differences in performance claims from the manufacturers but perhaps more importantly they are sometimes at a loss in making an optimal selection matching behaviour with a particular site condition. To this end a new testing methodology has been developed that can cater for the varying types of cable bolt behaviours. The methodology is based on the laboratory short encapsulation pull test (LSEPT) as recommended in the British Standard and overcomes several deficiencies such as cable rotation. Of most significance however, is its inability to measure the post-peak residual performance of high load transfer capacity cables and consequently, there is an inference that these cables may be susceptible to sudden anchorage failure with relatively little yield. This paper details the results of anchorage performance tests of a range of cable bolts and the differences in performance with rock strength and drill hole diameter.INTRODUCTIONA research project was undertaken to develop a new laboratory-scale test apparatus to study the axial performance of fully grouted cable bolts that are used in the Australian underground coal mining industry. Work by Thomas (2012) and others in recent years found there were a number of deficiencies in the testing methodologies making it difficult to determine and compare the performance of the dozen or more different types of cable bolts on the market. This has meant that geotechnical practioners have been hamstrung in optimizing the design of ground support systems in underground environments that are increasingly more arduous.A cable bolt is a flexible tendon consisting of a quantity of wound wires that are grouted in boreholes at defined distances between holes in order to provide ground reinforcement of excavations (Hutchinson & Diederichs, 1996). They were initially introduced into the underground hard rock mining industry in the 1960s (Thorne & Muller, 1964) and since the early 1970s have been brought to coal mining operations."

Jan 1, 2015

By G. Morin, G. Marin, M. C. Parr, J. Carignan

"Investment casting offers many advantages for the near net shape production of complex geometries, however, molten titanium reacts with most of the refractories used in investment casting shelling systems, which leads to the formation of an oxygen contaminated surface layer. This layer, called alpha case, is 0.1 to 0.6 millimeters in thickness according to the casting section size and must be removed either by mechanical or chemical milling processes. Alpha case removal processes affect casting tolerances and may contaminate the part intended for medical applications (e.g. embedding of abrasive grit media in the alloy). A shelling system based on an yttria prime slurry has been developed and was found to almost suppress the mold metal reaction. Yttria is an expensive refractory, but slurry life was found acceptable for small castings using a closed container and flow coating process instead of conventional pattern dipping. Alpha case depth has been determined for Ti6Al4V by metallographic techniques and microhardness measurements on different step block casting cross sections. Alumina and yttria second prime stuccos were evaluated in this study. The shelling system minimizes finishing operations in the production of casting for medical applications.INTRODUCTIONTitanium investment castings have been in the commercial market since the beginning of the titanium era in the mid 50’s. Investment casting is a cost effective way to produce complex parts for medical, aerospace and chemical processes applications. Investment casting of titanium is difficult due to the high reactivity of titanium with air and refractories used for shell mold building especially for the face coat. Melting is done under vacuum and no shelling system has been proven effective to suppress the mold-metal reaction yet. The main issue with the mold-metal reaction is the formation of an oxygen enriched zone at the surface of the castings named alpha case (Frueh et al., 1997; Kim, 2002; Saha, 1986). The alpha case is brittle, reduce the fatigue life in service of the parts and must be removed by chemical milling.For industrial purposes, calcia partially stabilized zirconia based slurries have become widely used in titanium investment casting for primary coats due to a combination of limited metal shell reaction. Calcia stabilized zirconia slurries have an acceptable shelf life and offer an interesting production window. Our experience shows that a resulting alpha case depth is 280 micrometers for a casting section of 6.35 mm in thickness is typical with such a shelling system (Morin, 2013)."

Jan 1, 2016

By P. I. Laforest, M. S. Moats

"Antimony in smelted copper anodes has been shown to cause problems in electrorefining including brittleness of starter sheets. In order to improve deposit properties, a study was conducted examining the effect of anode chemistry on cathode ductility and electrolyte chemistry. Two industrial anodes with different molar ratios of As/(Sb+Bi) were used in laboratory electrorefining experiments with commercial electrolyte, and the addition of commercial glue and Avitone. The ductility of 21-hr copper deposits was evaluated by a 180° bend test. X-ray diffraction (XRD) and metallography were performed on unbent specimens to characterize the deposit structure. Increasing the anode As/(Sb+Bi) molar ratio from 0.54 to 3.8 resulted in an increase, on average, from four to eight bends to failure in cathode material produced. Significantly lower concentration of antimony (V) in the electrolyte was detected when operating with the higher molar ratio anode. The presence of (111) and (200) planes was noted in cathode material produced from the higher molar ratio anode suggesting that mixed growth character could be responsible for the observed increase in bend test results. The ductility of the starter sheet materials was improved by a higher anode molar ratio.INTRODUCTIONThe presence of antimony in copper electrorefining electrolyte has been reported to cause problems in cathode production (Hiskey, 2012; Peng, Zheng & Chen, 2012; Wang, Chen, Zhou-Lan & Lian-Sheng, 2006; Wang, Chen, Zhou-Lan, Wang, Xiao & Zhang, 2010; Wang, Chen, Zhou-Lan, Wang, Xiao & Tang, 2011; Wesstrom, 2014). To better understand the impact of antimony, laboratory scale electrorefining experiments were conducted using industrial inputs (anodes, cathodes and electrolyte). The influences of anode chemistry on the valences of antimony and arsenic in the electrolyte were monitored and correlated to physical cathode characteristics, such as a bend test to failure and crystallographic orientation.Commercially, starter sheets are produced by electrorefining impure cast copper anodes onto titanium blanks. The starter sheets are then hung in an electrorefining or electrowinning cell using loops of bent starter sheet material. These loops, in the absence of sufficient ductility, fail resulting in cathodes falling into the electrolysis cells. It is thought that the reduction in ductility can be related to anode composition; in particular, the molar ratio of arsenic to antimony plus bismuth As/(Sb+Bi). It has been stated that maintaining this ratio above 2:1 results in numerous improvements to electrorefining operations (Baltazar, Claessens & Thiriar, 1987; Kamath, Mitra, Radhakrishnan & Shetty, 2003; Krusmark, Young & Faro, 1995; Noguchi, Itoh & Nakamura, 1995; Wenzl, 2008)."

Jan 1, 2016

By H. C. Cooke

"This paper has reference in a general way to the region extending from the north shore of lake Buron to the northern limit of the elliptical-shaped area generally known as the Sudbury Basin, and more especially to the district lying south of the Basin (Fig. 3). Attention is concentrated mainly on the structure of the district and, as space does not permit of much geological description, it is assumed that the reader has some knowledge of the general geology. The accompanying table outlines the sequence of the rock formations according to the most recent available information; for further details the interested reader may consult the publications of the various authors mentioned in the paper.STRUCTURE OF THE SEDIMENTARY ROCKS SOUTH OF THE SUDBURY IRRUPTIVEThe rocks south of the Sudbury irruptive, excluding certain intrusives, are, in order from north to south:(1) A band of basic lavas.(2) A band of well-bedded greywackes and quartzites, long termed the McKim greywacke.(3) The Copper Cliff formation, with McKim greywacke' both to the north and south.(4) The Ramsay Lake conglomerate.(5) A thick quartzite formation.All these rocks strike approximately east-northeast, dip steeply south, and generally face south, though there are local exceptions."

Jan 1, 1954

By A. Majumdar, B. Servière, H. Persson

The CCR refinery, which was built in 1931, treats both internal and third party copper anodes to produce 325,000 mt of copper as cathodes. These anodes contain high levels of impurities, such as Ni, As, Sb and Bi, that reports to the electrolyte during the refining step and need to be removed in order to maintain cathode quality and operating efficiencies. In the purification plant, the electrolyte is de-copperized via electrowinning in three stages. In the last stage, the copper content of the electrolyte is reduced to below 1 gpl in order to maximize the co-deposition of As, Sb and Bi with the Cu. This is accomplished with minimum arsine gas generation by using periodic reversal of the current and by controlling the final copper content of the electrolyte. Nevertheless, the possibility of exposure to arsine is treated as a major risk and controls have been implemented to reduce this risk. This paper describes the controls in place at the purification plant, which are being continuously improved through periodic risk assessments and audits. INTRODUCTION The CCR Refinery, which is a part of Glencore Canada Corporation and located in Montreal-East, Quebec, is a custom copper and precious metal refinery, with a capacity to refine 325,000 tonnes of copper anodes per year. Copper anodes are received from the Horne smelter in Rouyn-Noranda, Quebec, Altonorte smelter in Chile and other 3rd party smelters. CCR anodes are produced using the spent anodes from the tankhouse along with purchased spent anodes and copper scrap. The precious metal plant treats the tankhouse anode slime, purchased anode slime, precious metal ingots and Doré anodes from Glencore’s Brunswick lead smelter in Belledune, New Brunswick. CCR products include copper cathodes, silver and gold bullion, a platinum-palladium concentrate, selenium, tellurium dioxide and nickel sulfate. In 1975 an accident occurred at CCR where two employees were exposed to fatal levels of arsine emitted from the then existing purification cells. This process was therefore shut down immediately. Research and development work was then initiated to determine the optimum electrowinning conditions whereby arsine gas generation would be minimized while maintaining high copper and impurity removal efficiencies. It was found that the application of periodic reversal of current (PRC) during the last stage of electrowinning retarded the onset of arsine formation while at the same time allowing the copper concentration to be reduced to less than 1 gpl (Houlachi & Claessens, 1978). A new purification plant was designed based on the PRC technology and was started up in 1976. In addition to the use of PRC electrowinning, the new plant is located in a fully enclosed section of the tankhouse. A special effort was made to design a ventilation system to evacuate the acid mist in addition to any arsine gas. Arsine monitors were installed to measure the emissions from the stack along with arsine levels in the workroom. The arsine monitors and the ventilation system were interlocked with the rectifiers (Thiriar et al., 1983).

Jan 1, 2019

By D. Larouche, M. Mardan

Hot tearing is a complex defect in aluminium castings which is produced during solidification when a certain amount of liquid phase remains and weakens tensile resistance of the alloy. In direct chill casting of aluminium alloys, hot tears initiate at the surface of sheet ingots just after the primary cooling zone, where the microstructure is particularly vulnerable. In order to study the hot tearing susceptibility of these alloys, and the effect of grain refiners on their thermo-mechanical behavior , tensile tests were carried out in the semi-solid state ( ~95% solid) and at low strain rates using an apparatus called DCSS, for Direct Chill Surface Simulator. This apparatus, originally developed at Alcan Arvida R&D Centre (ARDC), is an instrumented rig test reproducing the conditions prevailing during the primary cooling stage of the DC casting process. The mechanical behavior of solidifying shells and the hot tear formation under applied tensile loads were measured and the occurrence of hot tearing was observed. Temperature in different locations of the casting, applied load and surface strain were monitored during the tensile tests conducted on aluminum alloys AA5182, AA6111 and AA3104. The microstructure of the tested samples was examined using the optical microscope to evaluate their columnar or equiaxed aspect and their effect on the mechanical response of the alloy. A special emphasis has been given to the evaluation of fractions solid existing in the castings at the start of the tensile tests, taking into account the local temperature, thermal gradient and cooling rates experienced. It was found that excessive grain refiner additions decreased the strength of solidifying shells because of the increased level of porosity induced by easier nucleation of new phases (gas included). It was also observed that cooling rates increased with the level of grain refiner, a phenomenon that was associated to the higher number of contact points obtained with small equiaxed grains. Finally, the concept of a stress based criterion for hot tearing was reinforced by the strengths obtained on not grain refined AA5182 and AA6111 showing similar fraction solid near the surface, but significantly different grain sizes.

Jan 1, 2006

By Paul Hammond

Abstract The Allard Lake ilmenite deposits, which are currently being developed on a large scale, occur as a series of dykes or lenticular, flat-lying bodies within the northeastern part of a large, oval shaped anorthosire mass of Precarnbrian age which lies with its long axis paralleling the gulf of St. Lawrence. The Lac Tio deposit, discovered by Kennco Explorations, Limited, in 1946, is the largest body of titanium ore of its type now known in the world. It contains upwards of 112,000,000 short tons of ilmenite ore averaging 32 per cent TiO2 and 36 per cent Fe. The ore is an aggregate of ilmenite with oriented microscopic blades of hematite. The deposits appear to be high temperature, late magmatic injections containing only a small amount of volatiles, and bear a genetic relationship to the anorthosite rocks in which they occur. * * * Introduction Recent developments on the ilmenite deposits in the Allard Lake district of Quebec indicate the probability of a major industry, and one which may make Canada the world's greatest producer of titanium pigments and, ultimately, of titanium metal. The presence of ilmenite in this district was first reported by the Quebec Department of Mines following a reconnaissance shore-line geological survey in the year 1941. The ensuing report by Retty describes the occurrence of a number of small ilmenite lenses about the shore of Allard lake and' along two smaller lakes in the vicinity. These showings were later staked by Toronto and Montreal interests who carried out a certain amount of development work, and were described in more detail by Longley for the Quebec Department of Mines. The claim groups were later optioned by Kennco Explorations, Limited, Canadian subsidiary of Kennecott Copper. None of the deposits in themselves constituted a sufficiently large body of ore to warrant the major construction expenditures necessary for their exploitation on a profitable basis. The surrounding anorthosite areas, however, were considered favourable for the possible occurrence of other ilmenite deposits

Jan 1, 1949

By M. Oliazadeh, A. Vazirizadeh

"The inclusion of small amounts of silicon, phosphorus and sulphur in iron ores or concentrates can have a profound effect on the steel making process and thus on the final iron and steel products. In nature however, it is inevitable that iron deposits contain unwanted elements. Each element has its own distinct effect on the final steel product. The effect of high silicon is the formation of gray iron. Phosphorus mainly increases hardness and strength, lowers solidus temperature and increases fluidity and cold shortness. Finally sulphur contamination causes cracks in the iron texture when smelting and forms white iron when casting. Overall, the acceptable level of phosphorus, sulphur and silica in the iron concentrate should be less than 0.04%, 0.15 % and 1.5 % respectively.Scarcity of high grade iron ores necessitates using lower grade ores with higher amounts of impurities. The purpose of iron concentrators is to increase iron grades to an appropriate level suitable for steel making as well as removing impurities. Although many impurities can be traced in the ore, the most predominant impurities are limited to one or two elements. In this paper the beneficiation methods for removing SiO2, P and S are presented, including flotation, and the parameters that need to be considered in the design of beneficiation plants are discussed. Finally industrial cases are discussed along with their metallurgical performance.INTRODUCTIONIn metal sector, value of iron ores and concentrates is determined by iron percentage as well ascontent of:• Useful elements (Mn, Ni, Cr, V, Ti): natural alloying elements in steel• Deleterious impurities (S, P, As, Zn, Pb, K, Na): impair metal properties or complicate operational process in blast furnace• Fluxing components (Si, Ca, Mg,, Al)Sulphur and copper result in red-short, phosphorus is the cause of cold brittleness and arsenic and copper decrease welding characteristics. Sulphur should not exceed 0.15 in commercial ore. Acceptable sulphur content in ores and concentrates for producing sinter and pellets is 0.6%max, as sintering and heat hardening of pellets remove sulphur 60-90%. Phosphorous content in ores, sinter and pellets is limited to 0.07%-0.15%. 0.00.1% As max, 0.1-0.2% Zn max and up to 0.2% Cu are allowed in iron-ore part of the blast furnace burden for the production of standard conversion pig iron. Slag-forming components are divided into basic oxides (Ca, Mg) and acidic (Si, Al). Higher ratios of basic to acidic oxides are preferred since this reduces raw fluxing material."

Jan 1, 2016

By E. H. Henderson

MR. R. V. NEILY stated that he had at one time operated at Goldenville. The practice and results are much the same now as in the olden days. Inside plates were then found to be a source of trouble and had been removed. At the Libbey mine, Queen's county, the sulphides carried considerable gold, and $45.00 to $60.00 per ton had been recovered from the concentrates by roasting and chlorinating. Later, concentrates were treated with bromocyanide. Following that practice, a cyanide leaching plant was installed, which did not require concentration of the tailings. Cyanidation brought a recovery of around 95 per cent, with but $300 worth of plant. In Nova Scotia, the ore of each locality presents an individual problem of its own as to treatment required. Ma. W. B. Timm stated that, in the majority of Nova Scotia gold ores, more than 75 per cent of the gold content is free-milling and, naturally, stamps are most efficient for collecting and amalgamating this gold. In Ontario and the West, they had got away from stamps, and perhaps the main reason was that the supply of battery-men, who came from Nova Scotia, had died off. Ball-mills had been installed, which required smaller space and handled large tonnage, even though, as far as amalgamation goes, the stamps were probably more efficient. If concentration is to be done, ore from stamps is usually in better shape for recovery in passing over the tables, as there is no slime. With the ball-mill, flotation is necessary. The better practice, undoubtedly, is to take out what gold is possible before it is all smashed up, as in the ball-mill, though recent developments in the ball-mill make it possible to trap and take coarse gold directly from the mill. In this way, cyanidation is speeded-up, due to saving of the time the coarse gold would take before going into solution. PROFESSOR A. E. FLYNN found it unusual in these days to read anything in favour of the stamp mill, and thanked Mr. Henderson for the excellent paper in which he upholds the stamps and backs his opinion with facts from actual operations. For the typical Nova Scotia ore, containing coarse gold, stamps are un¬excelled. It used to be said that the virtue of stamps is that they brighten the gold for amalgamation. Although this saying is almost classical, it is not true, for gold is never brighter than in the native, untouched state. Any hammering that gold gets makes it more difficult to amalgamate.

Jan 1, 1935

By Margarete Kalin

Mine Waste Management ?Reduction of Sulphideoxidation or inhibiting weathering of rocks Geologist - broken or ground rocks Hydrologist - sources of contaminants Mining engineer - waste sites Consulting companies - income units People - Ugly, bad, dead Ecological Engineer Landscapes which contain building blocks of an emerging ecosyste

May 1, 2013

By N. P. Hristov, L. V. Kuzev

"A simulation study of the fill factor of a drum mill was conducted using two types of grinding media: balls and tetraballpebs. Each medium was composed of equal number of grinding bodies having equal weight but different shape. The difference was in the density of the two grinding media.Standard spherical grinding bodies (balls), which were used in practice, and equivalent (by weight) grinding bodies in the shape of spheroidal tetrahedrons (tetraballpebs) were studied. The simulation was conducted in a module of a 1.2 m diameter drum mill, whose length exceeded twice the diameter of the corresponding grinding body. The grinding balls had a few percent (3 to 6) higher fill factor than the grinding tetraballpebs in the same shell.Vertical sections of the grinding medium were taken across the studied shell module along its axis. They showed the location of each grinding body in the fill volume. Defects in the packing of the grinding bodies and the contacts between them and with the inner surface of the shell were also show. Differences in the contact points of the balls and the tetraballpebs were noted. For the tetraballpebs, we observed contacts both between the spherical surfaces and with the edges and vertices of the grinding bodies.The topography of the grinding media is shown visually.INTRODUCTIONThe grinding balls have been studied extensively. It is the traditional grinding medium in ore processing industry. The parameter characterising the grinding medium is its density. It is the mass of the grinding medium per unit of volume. The parameter may have a range of values. It depends on:• The physical properties of the material they are made of;• The shape of the grinding body;• The dimensions of the body;• Size distribution of the grinding bodies in the grinding media.In comminution, the fill factor of the mill shell is the process parameter that is representative of the grinding medium. Some publications have indicated the disadvantages of ball grinding. For example, Wu, Xiang, Glen, and Duan (2008) note in the analysis of the mechanism of grinding that the balls are not the best grinding media and disadvantages include among others:• Easy over-grinding resulting from the point contact between the balls;• Attrition surface is the smallest in the grinding media;• Poor selective exposure of minerals resulting from the accidental and often significantly more powerful impact on the feed;• The grinding efficiency drops as the fineness of grind is increased;In the Handbook of mineral processing, Polkin (1950) noted that the shape of the grinding bodies determines the volume of the void spaces therein and therefore the shape affects the grinding efficiency per unit of volume of the grinding medium."

Jan 1, 2016

By Asanga S. Nanayakkara

The surface deformations induced by reservoir dilations can be measured using tiltmeters and these measurements can be used to infer reservoir level volume changes by solving an inverse problem. Preferred approach to solve such an inverse problem is to consider more tiltmeter measurements than the number of unknown variables considered in the inverse problem. However, sufficient number of measurement points is not always available due to economical and practical issues. This paper proposes a new approach to circumvent this problem. The new approach entails generation of pseudo surface deformation data by curve fitting tiltmeter measurements using a mathematical function, which delineates three-dimensional characteristics of surface deformation profiles. Then a three-dimensional inverse problem is solved using pseudo surface deformation data. This method is useful in inferring reservoir volume changes with high areal resolution when the number of available measurements is not sufficient to acquire the desired areal resolution.

Jun 1, 2012

By Richard Wells

Peabody Energy is the largest pure-play publicly traded coal company in the world. We have been in business 129 years and like most of the coal mining companies in the United States, since 1969 the majority of our safety improvement efforts had been driven by compliance with the various versions of the Federal Mine Safety and Health Act and the supporting federal regulations. In 2004 Peabody Energy management came to the understanding that in order to achieve our goal of zero incidents, that focus must change. This paper will describe the elements of the journey we began at that point to make the transition to a behavior and systems-based approach to safety management and our efforts to win the minds and hearts of our employees. This journey is undertaken with the goal of making safety truly a way of life for all Peabody Energy employees.

Aug 1, 2013

By Randy McMeekin, Chris Twigge-Molecey, J. Peter Blake

The business objectives of a metallurgical project determine targets and constraints, such as the range of products, production capacities, in-service dates, and capital and operating cost parameters. Permitting is usually left to the project team, as are decisions regarding site location, technology, and construction approach. Success requires an orderly methodology, represented in this book by front end loading (FEL) phases: FEL1 examines several alternative approaches; FEL2 ranks and eliminates less economically or technically attractive options; and FEL3 develops the preferred option to the point of major permit completion, with defined scope, schedule, and cost to submit for approval to proceed with implementation in FEL4. Working through FEL1, FEL2, and FEL3, the project definition improves, estimates become more accurate, and project risks are reduced. The project design basis at the end of FEL3 is the control document for project implementation in FEL4.

Jan 1, 2015

By T. G. Joseph, M. Welz

ABSTRACT: Joseph (2002) introduced passive seismic monitoring to measure mining equipment performance. This paper evaluates the potential of passive seismic monitoring to correlate mining equipment operation with oil sands surface response, with a mining hauler as the seismic source. When applied to moving haulers, this action–reaction approach is complex. Vibrations from on-board equipment, such as pumps and tires, dirty the signal with noise. To facilitate any correlation, the signal must be cleaned up. Existing geophysical analytical techniques were manipulated to evaluate the noise problem and to filter sufficiently to permit an evaluation of whether a mining equipment action–ground response relationshipis in fact discernable.

Jan 1, 2011

By Baochun Wang, Hongli Jia, Zhaolian Wang, Fengliang Liu

"Promote and apply a new beneficiation technology and equipment effectively processing the refractory and medium-fine grained weak-magnetic minerals. HUATE® Forced-oil Cooling Vertical Ring WHIMS adopts the transformer oil cooling technology to cool excitation coils, solving the easily generated scaling problem resulting from water cooling, thereby to eliminate the demineralized water system. With <25 temperature ?raise, its magnetic field is stable. Wrapped by outer magnetic armor, it can generate a background intensity 1360kA/m. It effects very well in 1) wet preseparating the weak-magnetic coarse grains, like hematite, manganese ore, ilmenite, and purifying the concentrate; 2) removing the ferrous impurities and purifying the non-metallic minerals, like quartz, feldspar, kaolin; 3) enriching and recovering tailings from non-ferrous metals, like copper, lead, cobalt, molybdenum, thereby to greatly improve the mine resource utilization. It has applied 14 relative patents in China, and the invention patent in 56 countries, like Russia, USA, Australia, via PCT international organization. HUATE® WHIMS has been applied and accepted in more than 100 mines in and out of China. Compared with water cooling vertical ring WHIMS, it’s energy-saving and water-saving, and avoiding generating the scale. While compared with JONES WHIMS under the same separation indexes, it’s featured of more space-effective, lighter, lower costs, higher gradient, higher efficiency, larger processing capacity and wider grain application scope. Greatly promoting development of mineral processing technologies, HUATE® WHIMS is the equipment to reduce costs and improve efficiency urgently needed by the mine enterprises now.INTRODUCTIONAt present, influenced by the price and production factors, the international market demand for the grade of iron ores is increasing continuously. Restricted by the ore occurrence state, the beneficiation technology level and product economic value, every year the stope strips the stockpiling and discards hundreds of millions of tons of waste rocks containing iron, especially the weak magnetic hematite and limonite with <20% Fe%. The utilization technological bottleneck of these waste rocks makes their concentration ratio as high as 5-6, which leads to the huge wastes of energy, materials and beneficiation reagents and the increase of production costs. The effective solution is to improve the selected Fe% of the waste rocks like hematite. With the successful application of HPGR technologies in Chinese large iron mines, the mill feeding size has been reduced to 6-0 mm or 3-0 mm from the original 15-0 mm in the crushing system with 3 stages of crushing and 1 stage of closed circuit. This creates the conditions for the wet separation and recovery. While for the medium-fine grained weak-magnetic minerals, it lacks of the effective separation and recovery equipment in the world, which’s badly in need of R&D of the medium-fine grained high gradient wet strong magnetic preseparation equipment."

Jan 1, 2016

By Cristina Echavarría

MAIN POINTS ? The region: opportunities and limitations ? Overview of main issues emerging from MMSD in South America ? Who comprises the local community? ? What are the main challenges? ? Some suggestions for companies to improve their contribution to local sustainable development of mineral rich localities THE REGIONAL CONTEXT 1. The region is a producer of minerals contributing over 20% to world metal production. It consumes only 8% 2. Significant diversity of national contexts-both between countries and within countries 3. Variable but predominant need for strengthening of government and community institutions and governance, especially at the local level 4. Dearth of baseline information for decision making 5. Sustained social spending during early 90?s as a consequence of economic recovery and fiscal policy, produced important advances in education and health 6. Despite government efforts in most countries poverty continues growing 7. Highly inequitable distribution of wealth persists

May 1, 2002