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By H. P. Kritzinger, T. C. Kingsle

"Rotary kilns are used for a variety of mineral processing operations. Hatch makes use of a kiln model developed from first principles to evaluate designs for its clients. This tool has been applied to a variety of pyrometallurgical applications, including ferrovanadium, nickel carbonate, nickel laterite, iron ore reduction, and spodumene (lithium) production.This paper illustrates the application of numerical optimization techniques in combination with the kiln model in the interrogation of a generic iron ore reduction process. The fundamental modelling concepts are explained, followed by a description of the optimization approach. The results show how the combination of the two methods, with modern computing power, can generate a large number of viable design and operating candidates."

Jan 1, 2015

By P. J. Williams, A. R. Foster

Petrographic studies, assay records, and laser ablation-inductively coupled plasma-mass spectrometer (LA-ICP-MS) analyses of major sulfides suggest nearly all of the gold at the Ernest Henry Cu-Au deposit occurs in the form of native gold or electrum (95-65 wt.% Au); sylvanite and dissolved gold in cobaltite, chalcopyrite, and pyrite make only minor contributions. LA-ICP-MS analyses of the gold contents of chalcopyrite gave from 8 to 139 ppb (mean = 56 ppb), more than an order of magnitude lower than those experimentally determined in chalcopyrite in equilibrium with native gold at the estimated mineralization temperatures (350°-450°C). Gold content is more variable in pyrite (1-400 ppb, mean = 77 ppb) and highest in narrow growth zones of a subordinate type of complexly zoned pyrite wherein it is associated with elevated As, Ag, Sn, Sb, Te, and Bi. Deposition of gold-electrum was closely associated with, but preceded some of the chalcopyrite deposition, as indicated by microtextures and lower bulk Au:Cu ratios in late-stage chalcopyrite-rich veins. Gold grains have maximum dimensions from <1 to 50 micrometers, and are heterogeneously distributed with most occurring in microscale clusters. Fifty-five out of 76 grains recorded in polished sections are in contact with both chalcopyrite and pyrite, and many of the rest are in sites where such a relationship could exist in the third dimension. The dominant textural sites are intergrowths with chalcopyrite in microveinlets cutting pyrite, and on faces of pyrite grains in contact with chalcopyrite. Scanning electron microscopy, electron microprobe analysis, and proton induced X-ray emission studies show that pyrite associated with gold includes complexly zoned, weakly zoned, arsenian, and arsenic-poor types. The textures are compatible with the possibility that most gold was deposited electrochemically as native metal on pyrite surfaces. The textural distribution of gold has important metallurgical implications given that the ore processing circuits at Ernest Henry and most other sulfide copper mines are designed to exclude pyrite (and arsenic) from concentrates.

Jan 1, 2007

Collaboration between education providers is the key to long-term sustainability and improved quality in mining education. The mining industry is now, more than ever, an industry doing business on a global basis. Staff are recruited by global mining companies in many different countries and can find themselves deployed anywhere in the world. The mining engineer of tomorrow must be willing to take on this international challenge, and must be educated to a level where he or she has a comprehensive grounding in technical aspects of mining engineering, but also a well-founded appreciation of management, social, environmental and cultural issues that may be encountered around the world. In order to deliver such an education, academic providers must collaborate at both a national and international level. This paper provides an overview of progress that has been made in Australia through the national joint venture ? Min¬ing Education Australia (MEA). Supported by the mining industry in Australia, through the Minerals Council of Australia (MCA), MEA has been operational since 2007 and is seeing the development of a range of innovative courses and delivery methods, together with a high level of staff cooperation across the country. MEA has also commenced some international teaching initiatives that are seen as a catalyst for a far greater degree of international collaboration in the future. Such activity is not only to the benefit of the students who are taught by experts from around the world, but it also ensures that individual univer¬sity programs remain viable in terms of staffing numbers and financial performance. The paper also presents some statistics on recent upward trends in mining engineering student numbers from around the world, in response to the global shortage of mining engineers.

Jan 2, 2010

By Brian Reid

"This paper studies the progress made by hydraulic shovel manufacturers over the last few years, particularly in the areas of productivity increase and operating cost reductions.Five years ago, it was widely considered that the unit production cost for a hydraulic shovel in a mining application was double that of a cable shovel in the same application. The hydraulic machine manufacturers have taken up this challenge, and modern improvements in design, coupled with changes in maintenance techniques, have narrowed the gap to the point where it is valid to ask the question ""will the cable shovel exist in ten years&apos; time?"".Historical BackgroundThe history of the cable shovel goes back to the early 19th century and the industrial revolution. Early machines were steam-powered and ran on rails.The ""power shovel"" and the ""dragline"" were the only mechanical means of mass excavation until the early 1950s. Rail-mounted units gave way to crawlers, which increased flexibility considerably. Some shovels were redesigned as backhoes, and some became extremely large when designed as stripping shovels primarily used in North American coal mines.In the early 1950s growth in hydraulic technology spawned the introduction of the hydraulic excavator, which soon began to replace the smaller cable shovels and backhoes used in the construction industry. They were completely self-contained with either a gasoline or diesel engine and, being much lighter, were more readily transportable.As the excavators grew in size from its early models of 0.5 m3 or less, many of the cable shovel models were discontinued. This was not surprising for several reasons, but the most obvious is that both were often made by the same manufacturer."

Jan 1, 1988

Mine drainage and mine reclamation are topics of major interest to the mining industry, federal and local governments, and the general public. This publication and its companion three volumes are the proceedings of a conference held in Pittsburgh, Pennsylvania, April 24-29, 1994. There were twelve sessions (69 papers) that dealt with mine drainage, including modeling, geochemistry, prediction, treatment, control strategies, characterization, hydrology, and case studies. These sessions comprise volumes 1 and 2. The six sessions (34 papers) that dealt with reclamation and revegetation of disturbed lands are included in volume 3. Volume 4 includes the six sessions (34 papers) that dealt with such topical issues as fires at abandoned mine sites, subsidence, hydrology, mine wastes, and policy. Poster session presentations are represented by 49 papers and 92 abstracts that have been placed in the back of volumes 2, 3, and 4, consistent with the subject of that volume.

Jan 1, 1994

By B. Denby

Paper presented at a meeting on: Artificial intelligence in the minerals sector, held in Nottingham, UK, 20 April 1993. The design and scheduling of open pit operations are consistent problems encountered by the surface mining industry. Numerous techniques and algorithms have been developed to assist the mining engineer in the creation of optimum development strategies. Virtually all the practical techniques that have been produced have concentrated on one of the aspects (limit definition or scheduling) at the expense of the other. It has long been recognised, however, that the two activities are intrinsically linked and thus solving either problem independently of the other can only ever produce sub-optimal results as a whole. This has been termed the "circular reasoning problem". It has also been recognised that, for all practical-sized situations, solving both problems simultaneously is virtually impossible using conventional techniques due to the massive size of the search space involved. A technique is presented which is based on a self-learning genetic algorithm, which provides a combined pit limit and extraction schedule simultaneously in order to maximise the NPV (net present value) of the extraction. The theory is developed in two-dimensions and a number of examples of its application are presented. It is proposed that this approach is a highly efficient, heuristic technique offering the potential to transcend the circular reasoning difficulties of separate pit limit and extraction scheduling systems. Extension of the technique into three-dimensions and its application to realistic problem sizes are discussed

Apr 1, 1994

By Frank van der Meer, Jorge Portocarrero, Alexandra Gruendken

"The number of High Pressure Grinding Rolls (“HPGRs”, also called Roller Press) installations instead of tertiary crushers is rapidly increasing. The technology has been largely accepted in the minerals industry and benefits, such as superior energy efficiency and a lower overall operating cost compared to alternative technologies, have been demonstrated at a number of operations throughout the world.This paper focuses on coarse hard ore operations and reviews the successful installation of the first Roller Press installed instead of a tertiary crusher at the Los Colorados Plant of CMH (Chile) in 1998. It details the experience obtained over the past ten years of operation from commissioning to the present day. It highlights examples of further developments made in the design to improve machine maintainability and availability as well as wear life of the grinding surfaces.A second focus lies on procedures to derive from small scale testing material properties such as wear life, flake formation and strength and their application to industrial size machines to optimize circuit design, especially when Roller Presses are used in closed circuit with screening.INTRODUCTIONRoller Presses (also known as HPGR, High Pressure Grinding Rolls) are considered today state of the art for the preparation of pellet feed. They are also gaining wide acceptance in coarse ore operations. One of the first successful operations in which a roller press was used to replace a conventional tertiary and quaternary crusher is the Los Colorados plant of CMH in Chile.When the Roller Press at Los Colorados was commissioned in 1988, there were 169 Humboldt Wedag roller presses in operation throughout the world. Of these, 14 were installed in the minerals industry. However, these were installed mainly for grinding pellet feed to increase the Blaine value. Up to that time, only three KHD roller presses had been applied for crushing coarse ore in specialized circuits. Moreover, the installation at Los Colorados was the first Roller Press ever to replace a conventional tertiary and quaternary crusher in a hard ore application."

Jan 1, 2009

By G. W. Harris, J. J. K. Daemen

Slightly shorter, modified version also published in CIM Bull., vol.94, no.1047, Feb. 2001, p.52-55. To minimise ore dilution induced by blast movement in surface mines it is necessary to quantify such movement. This will allow more accurate location of the grade boundaries on the surface of a blasted rock pile before excavation. A method has been developed and tested for measuring accurately the direction and magnitude of subsurface blast movement, using a caesium vapour gradiometer and a real-time, differentially corrected global positioning system to locate the pre- and post-blast positions of magnetically enhanced target objects placed in blastholes inside a bench. The procedure does not necessitate disturbance of the blasted rock and the movement information is available sufficiently quickly to allow for modification of the selective mining boundaries for each surveyed blast. It was found that the maximum depth of target detection was 18 m and the overall accuracy was plus or minus 1 m horizontally and 1.2 m vertically

Jun 21, 1905

Jan 1, 1996

By James D. Nickerson

Thee Brightwater water treatment facilities, currently scheduled to be completed in 2010 and begin operating in 2011, will serve the northern part of King County, WA. The facility includes a new treatment plant and extensive conveyance system consisting of more than 21 km (13 miles) of influent and effluent conveyance tunnels and five portals. The majority of the conveyance system tunnels are mined by tunnel boring machines (TBM) and microtunnel boring machines (MTBM). Tunnel and portal construction is divided into three main contracts. The Ballinger Way receiving portal, constructed under the central tunnel contract, is the terminus for the BT-3 leg of the central contract and the BT-4 terminus of the west contract. The shaft has a 7.3-m (24-ft) finished inside diameter (ID) to accommodate removal of the central project TBM and the west contract TBM and extends to a depth of 66 m (216 ft) below grade through a complex and challenging soil profile characterized by multiple ground water tables. Vinci Grand Projects/Parsons/Frontier-Kemper Constructors (VCFK) was the joint venture team for the Ballinger Way portal. Frontier-Kemper was responsible for the shaft sinking. VCFK evaluated either slurry wall techniques or ground freezing for earth support during excavation of the portal and liner installation. The selection process took into account the vertical depth, cost, past practice, geology, water tables and a 9-m- (30-ft-) thick zone of contaminated soil at the top of the shaft. Ground freezing, which would also act as a hydraulic barrier, was deemed the better option for this project. The contract was awarded to New Jersey-based geotechnical contractor Moretrench. Typically, frozen walls, by design, key into an underlying cutoff. At the Ballinger Way portal, however, the [ ] freeze bottomed out in a substantially thick stratum consisting of predominantly clay, but with some inclusions of permeable soil that indicated significant ground water pressures. To ensure stable conditions at the bottom of the shaft, Moretrench, which also specializes in dewatering, designed and installed a perimeter array of deep wells to temporarily depressurize the permeable soils. The movement of ground water generated by pressure

Jan 1, 2009

New Bio-Adsorber with Activated Carbon and Nano Tube Carbon for Separation of Nickel and Cadmium

Sep 13, 2010

Vein swarms in metamorphic terranes such as the Otago Schist Belt, New Zealand provide evidence of past hydrothermal flow systems leading to fault initiation and reactivation. A major episode of hydrofracturing and fluid redistribution occurred during early Cretaceous exhumation of the schist belt. As a result, presently exposed lower greenschist facies greyschists in NW Otago are pervaded by abundant quartz-filled hydraulic extension fractures with associated normal faults hosting quartz¦scheelite¦gold mineralisation. Once the effects of Cenozoic folding have been removed, a regional subhorizontal schist foliation contains an aligned array of subvertical hydrofractures striking NNW, striking parallel to a set of low-slip conjugate normal faults; the array extends over an area >1500 km2 and over a depth interval >5 km. The hydrofracture array comprises a mesh of interlinked extensional-shear and pure extension veins. These veins show mutually cross-cutting relations. Extensional hydrofracturing apparently preceded the development of major throughgoing normal faults. Low-displacement normal faults are infilled with laminated quartz (¦ scheelite) veins (

Jan 1, 2002

By Mehmet Canbazoglu, Kaarlo Haavanlammi, Hannu Laitala

Cobalt is currently a critical metal because of the increasing number of electrical vehicles forecast for production. Copper and zinc are base metals that are used in many everyday applications, including vehicle production. Eti Bakir Co. Mazidagi Phosphate Plants in the Mazidagi district of Mardin, Turkey is a multi-product facility that produces cobalt, copper, and zinc, as well as fertilizers, from the roaster calcine. Roaster off gas is treated in a sulfuric acid plant (SAP) and the acid itself is utilized in fertilizer production. The comminution circuit, roaster, SAP, and calcine leaching process were developed by Outotec and integrated with the fertilizer production process implemented by Eti Bakir A.Ş. This paper describes the hydrometallurgical calcine leaching process used at the plant, with a focus on the oxidative pressure leaching of the cobalt, zinc, and copper-containing calcine. The cold and hot commissioning phases of the pressure leaching autoclave start-up are discussed together with experiences from the ramp-up period. The production processes of the copper cathode and cobalt and zinc-containing salts are also presented together with some of the plant’s operating parameters. INTRODUCTION The ETI Bakir A.S. fertilizer plant, Turkey, is located in Mardin Province near the border with Syria, (Figure 1). The leaching plant project was started in 2012. The purpose of the plant is to separate the valuable metals from the calcine produced by the pyrite roasters, which are used to produce a SO2 containing gas for the new sulfuric acid plant. Fertilizer production requires sulfuric acid, and for this reason a sulfuric acid plant was built; customer already had access to pyrite concentrate, which is used as the roaster feed. During the engineering phase of the roaster and acid plants it was noticed that the roasted calcine contained considerable amounts of valuable metals like cobalt, copper, and zinc. To recover these metals, a calcine leaching process was developed at the Outotec Research Center in Pori, Finland. The main process connections of the Mazidagi site are shown in Figure 2.

Jan 1, 2019

By F. W. Wood

The Bureau of Mines has sought clarification of the Ti-TiN system by studying the phases formed by diffusion reactions between titanium and titanium nitride. Reaction couples were prepared by embedding pockets of TiN powder in arc-melted buttons of titanium. Specimens were vacuum annealed at nominal temperatures of 800°, 950°, 1,200°, and 1,500° C. Metallographically mounted cross sections from reacted specimens and from some that were not annealed were examined optically, with an electron microprobe, with an election microscope, and by X-ray diffraction. Each annealed specimen contained a segregated core primarily of d-phase material, an ?-phase diffusion layer, an a-phase diffusion layer, and host metal. On the basis of corresponding microprobe analyses, and considering results of certain other research, a new phase diagram is proposed. It contains no qualitative innovations, only quantitative adjustments. Results were also analyzed from the viewpoint of diffusion behavior. Diffusion coefficients calculated for the ? phase were sufficiently scattered that the parameters are very tentative. Nevertheless, the diffusion behavior reported is in reasonable agreement with one of two prior studies if it is assumed that the earlier investigators were mistaken in their identification of the nitride phase in which the diffusion occurred.

Jan 1, 1974

By L. T. Stanley

A method is described whereby the behavior of the front is approximated when gas is injected into a thick reservoir having reasonably homogeneous properties. The method is applied to the Abqaiq field of Saudi Arabia. The producing member is the Arab-D, a high-permeability calcarenite which has no continuous betlding planes. Field performance indicates the injected gas to be partially miscible with the reservoir oil because gas volume factors experienced are lower than those predicted by the gas law. Eqlrilibril~m calculations confirnz ihis and also show that the volume factor may vary appreciably, depending on the relative quantities of oil and gas in contact in the reservoir; consequently, volutnetric balances are made for the purpose of determining the behavior of the gas volume factor during injection history. The effect of gravity segregation on position and shape of the gas front is approximated by dividing the producing section into three zones vertically and tracing the movement of the average interface in each zone, with counterflow of oil and gas taking place betweell zones behind the front. This results in a gas front that advances more rapidly along the top of [he formation than along the base, producing an "umbrella" effect in cross section that becomes more pronounced as the front progresses. The calculations cover the gas-injection period of Abqaiq field history through 1958, and the position of the gas front is plotted at one-year intervals. Finally, some comparisotls between the calcrlated fronial position and the gas-oil contact as Measured by neutron logs are made. INTRODUCTION Fig. 1 is a structure contour map of the Abqaiq field. For analytical purpcses, the field has been divided into two areas designated A and B, as shown on the map. Gas injection into Area A was begun in early 1954 into two wells located near the crest of the structure on the north-south axis of the anticline. During the period covered by this paper, the average injection rate has been 122 MMscf/D with a maximum sustained rate of 160 MMscf/D. The reservoir pressure has been maintained at 2,450 psig since start of gas injection. The reservoir originally was undersaturated but, prior to pressure maintenance, the pressure was drawn below the bubble point in most of the Area A section, creating an in-place free-gas saturation of 8 per cent at the crest of the structure. The average critical gas saturation is 13 per cent established by laboratcry core tests. That the entire reservoir remained below critical gas saturation prior to gas injection is borne out by the fact that none of the crestal wells have exhibited high gas-oil ratios during production history. The Area A reservoir is a carbonate section about 200-ft thick having average porosity and permeability of the order of 22 per cent and 500 md, respectively. The productive horizon is the Arab-D member of Jurassic age and is encountered at an average depth of

Drilling at Ipswich during the last twelve years by the Queensland Department of Mines has proved large quantities of reserves which have assured the security of the field for many years to come. This is perhaps the greatest contribution to the development of the field since its discovery in 1827.The drilling campaign commenced in 1950 and by the end of 1961 comprised 242 holes totalling 180,220 ft.Intersections of formations and seams, accompanied by detailed surface mapping, led to more precise knowledge of the geology of the field than was previously possible, and clarified many problems of correlation. Productive formations are part of the Middle Triassic Ipswich Coal Measures, a 4,300 ft sequence of fresh-water sediments with some interbedded volcanics. They are overlain by the Upper Triassic Bundamba Group and the Lower Tertiary Booval Group.Reserves disclosed by drilling amount to 171,487,000 tons, comprising 109,407,000 tons &quot;measured&quot; and 62,080,000 tons &quot;indicated&quot;. The security of these reserves encouraged many collieries to instal modern efficient mining machinery and washing plants.The climax of recent development of the resources of the field will be the commissioning in 1966 of a &#163;33 million 360 MW power station in the Swanbank district which will consume 14 million tons of coal during its 30 year life and will have a peak demand of some 20,000 tons per week.Drilling is continuing and is expected to prove additional reserves which will justify further development of the field.INTRODUCTIONUntil 1949 there had been no concerted effort to test systematically the resources of the whole Ipswich field. Fifty two known holes totalling 30,500 ft had been drilled, eight of them by the Department of Mines, but because of poor core recovery and inadequate records most of them were of little use in a comprehensive assessment.Development of the field was being retarded by uncertainty regarding reserves and by the general state of the coal mining industry. Numbers of comparatively small independent companies and owner groups were operating coal...

Jan 1, 1963

By Laura Bustemante, Bruce Vandenberg, Fred Huettig

Recent advances in solid-state, field portable, fast framing video camera systems and PC based frame capture hardware now allow blast imaging up to 1000 frames per second. Up to 8 seconds of data can be stored directly into the unit, downloaded to a PC or archived to a standard VCR without data compression. Since no film processing is involved, motion analysis can be performed instantly and on-site within a few minutes. This paper will describe the design features and applications of the KineView 1256P system and compare these with the analogous aspects of fii based cameras.

Jan 1, 1998

By Norman K. Olson

A geologic investigation of mineral resources in South Carolina first began in 1825 when the General Assembly authorized Lardner Vanuxen to conduct a "Geological and Mineralogical Survey of South Carolina." Vanuxen, South Carolina&apos;s first State Geologist, reported in 1826 on the limestones (marble) of the Piedmont which during those early years, were burned in many shall, scattered kilns in the region wherever suitable raw material was available. He also mentioned the possibility of using marl from the Atlantic Coastal Plain province for direct application and enrichment to the soil. Since before the year 1844 industrial minerals in South Carolina have been commercially produced literally from A to Z, asbestos to zircon. The first pub¬lished reports of actual commercial production, not just an occurrence, are referenced in Table 1 for 33 known industrial minerals and rocks in South Carolina. Known or suspected occurrences of undeveloped non-metallic mineral resources in South Carolina await future verification by geologic mapping, sampling (including coring), possible beneficiation, and market analysis. These industrial minerals and rocks include, but are not limited to, special, clay minerals (e.g. bentonitic clays, zeolites and others), sillimanite, argillite (lightweight aggregate), kaolin (alumina) and marl (underground storage and tunneling medium). In addition other non-metallic minerals, once mined but still worthy of reconsideration, include topaz (industrial), heavy minerals, barite, feldspar, and monazite. Finally, possibilities for new reserves, as an expansion of existing mine output, might develop for fuller&apos;s earth, limestone (lime), sericite (finely divided mica), vermiculite, kaolin (paper coating and filling, other filler), and metallurgical gravel. Official South Carolina data from the U. S. Bureau of Mines for 1974 indicated a total value of mineral production of $105.2 million. During 1974 production consisted of cam-on clays, (brick and tile), fuller&apos;s earth, kaolin and vermiculite

Jan 1, 1977

By B Leisemann, M Watkinson

Coal augering is an ideal method for recovering coal from the highwalls of open cut coalmines. Coal augering is a simple process whereby additional flights are added to the auger cutting head and auger holes are drilled at 1.9 m diameter up to 200 metres deep. Traditional monitoring was located at the mouth of the hole and if methane was encountered above two&#160;per&#160;cent, inert gas was delivered into the mouth of the hole to deplete the oxygen content at the auger cutting head below 12&#160;per&#160;cent. The auger operator was asked the question ‘how do you know that this is the case?’ Trials were undertaken to prove that the oxygen content at the cutting head did drop below 12&#160;per&#160;cent (the lowest limit for methane to ignite, also known as the oxygen nose point). Initial trials showed that the oxygen content in the mouth of the hole did not drop below 12&#160;per&#160;cent and modifications were made to hold the inert gases in the mouth of the hole so that the auger flights could take this inert gas into the hole. In-hole monitoring, after completion of mining and after extracting the auger flights, showed that the atmosphere quickly returned to fresh air. In-hole monitoring was also tried during the augering process and yielded valuable results. This paper will discuss the results of the monitoring, information on the gas results obtained and the methodologies used to optimise the oxygen content at the auger face.CITATION:Watkinson, M and Leisemann, B, 2017. Inertisation of coal augering holes, in Proceedings Australian Mine Vent Conference 2017, pp 293–298 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

The income of the Institute is derived mainly from dues, advertising in MINING AND METALLURGY and sale of publications. These sources are fortunately supplemented by the interest from invested funds now amounting to over $500,000, a considerable portion constituting endowments for especial purposes. Aside from the medal funds the principal endowments are the James Douglas Fund for support of the Library, the Rocky Mountain Fund and the Seeley W. Mudd Memorial Fund. The income from the two last named is available for the support of research and a variety of other purposes. It is allocated by the Board of Directors upon recommendation of standing committees in each case. An active effort is being made to increase the endowments of the Institute, it being felt that unusual opportunities exist for research and public and professional service through the organization.

Jan 1, 1939