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By Connor Meinke, Shaihroz Khan, Kevin Erwin, Rajiv Chandramohan, Muhammad Usman Siddiqui

A geometallurgy study aims to link metallurgy and geology to reduce technical risk and enhance the economic performance of a mineral-processing plant. It does so by accounting for variability in a deposit to develop cash-flow models with variable throughput rates. High-quality sample selection for metallurgical test work that is representative of the deposit is an essential component of a geometallurgy study, but the large multidimensional data set makes sample selection a daunting task, as classifying the data set while respecting its heterogeneity is difficult. This paper presents a streamlined approach for sample selection, using statistical analysis techniques in Python. It cuts down time to select samples from around 1,200 s per drillhole to about 60 s for data classification and from 12 h to 8 h for handpicking samples from the classified data set, translating to cost savings. The cumulative sum method and k-means clustering method are used in the methodology to elegantly classify the data and select representative samples. The effectiveness of the methodology is demonstrated by presenting data from a prefeasibility study of a copper-iron mine in which 40 samples were selected for flotation test work.

Dec 1, 2024

By Robert N. Morris

Ladies and Gentlemen: It is a distinct pleasure and honor to appear before you representing the railway industry as I do, but there is a much closer personal relationship. I am a graduate Mining Engineer and worked in the coal industry for 15 years prior to becoming a railroader only 4 ½ years ago. I have been a member of AIME most of my adult working life and am currently active in the Washington, D. C. Section. While having been in the railway industry only a short time, I have become involved during the recent period of innovation and development of the new railroad technique known as unit train service. I have had the privilege of helping to work out a number of unit train movements to both electric utility companies and to a major steel concern, handling coal from mines on the Southern Railway to the consuming plants. On Southern, our unit trains are all of what I shall describe as shuttle train operations whereas within the railroad industry today several types of service are characterized as unit train service and many don't offer comparable efficiencies.

Jan 1, 1968

By Amy Gartman

"Seafloor hydrothermal systems result in the emission of abundant particles and nanoparticles into seawater1. Many of the elements in these particles settle locally, although some are transported distally to the global ocean2. Although broad similarities exist, the mineralogy, size and therefore reactivity of particles emitted varies between sites in the global ocean, and even within sites at the same vent field. The particle geochemistry of these vent fields is a critical but little understood component both from a perspective of baseline characterization and potential environmental impacts.The mining of seafloor massive sulfides formed from hydrothermal venting will generate a new class of particulates in the deep ocean. Broadly, black smoke and SMS tailings exhibit similarities including abundant Cu, Fe and Zn sulfides, and a large number of submicron particles. In addition to the major minerals, minor minerals including As, Bi, and Pb are present, especially in back arc settings. However despite broad similarities, natural “black smoke” and crushed sulfides created during mining operations differ significantly in size class, morphology, abundance, and reactivity. A comparison of these two classes of particulates will be presented, including chemical composition and reactivity to dissolution and oxidation."

Jan 1, 2017

By Joel F. Flurnerfelt

Molten Al and Al alloys containing si, Mn, Ti, and y have been lanced with nitrogen-bearing gases. These lancing experiments provided the means for observing what phases form during exposure to nitrogen-bearing gases for finite periods of time, <2 minutes, at high temperatures, >1290oC. The experiments were conducted in sn induction heated drop tube furnace apparatus. The overall premise of these experiments was to select those Al alloys and gas compositions that show promise of forming secondary dispersoid phases, particularly AIN, in the Al matrix. The alloys selected will be atomized using gas atomization reaction synthesis (GARS) using the most favorable conditions. In this case, the chosen Al alloy will be atomized with a nitrogen-bearing gas, such that the Al and gaseous nitrogen species react to form a dispersoid phase within each powder particle. The powder particles that result from this "aggressive" GARS-process would be essentially Al metal-matrix composites within a uniform distribution of dispersoids. To date, only high-purity Al has been atomized using a mild GARS reaction. This work is funded by the Materials Science Division of DOE-BES under contract number W-7405-Eng-82.

Jan 1, 1996

By O. Celep, T. Uslu, Savas

This study investigates the enrichment of a low-grade colemanite concentrate (-3 mm) using a Knelson centrifugal gravity concentrator. Due to its low boron content, the concentrate is unsaleable and has to be stored under appropriate conditions to avoid potential environmental problems. The low-grade colemanite concentrate was comminuted to size fractions of-1 mm, -0.5 mm, and -0.15 mm before treatment in the Knelson Concentrator. The effects of particle size, fluidizing water velocity, and bowl speed on the enrichment process were examined. The B2O3content of the concentrate was increased from 33.96% to a maximum of 45.52%. B2O3recovery increased with increasing bowl speed and particle size, and decreased with increasing fluidizing water velocity. The enrichment process also rejected arsenic and iron to some extent, with a maximum reduction of arsenic from 1360 g/t to 765 g/t and iron from 0.88% to0.33%.

Jan 1, 2015

Bauxite Resources Limited is grade drilling in its Western Australian Darling Range tenements to firm up resource definition and to develop mine plans. The Darling Range bauxite is generally in shallow deposits with minimum overburden. In the northern tenements, the ore is characterised by a higher silica layer which may extend from 0.5 to 1.5 m below, which high grade bauxite is found to a depth of four to 7 m. When grade drilling samples are taken, every 0.5 m and the recovered sample is weighed, logged and bagged. To eliminate splitting errors, the whole sample over the short interval is pulverised. Twinning holes variations are observed when using various drill rigs. Diamond core has been shown to give close to 100 per cent recovery and grades have been verified by digging bulk samples. As such, diamond core is used as the reference. It is intended to include sonic drilling as an alternative to diamond cores. This presentation details and attempts to explain the reasons for the observed variations in the various drilling methods used by Bauxite Resources Limited. This is an ABSTRACT ONLY no paper was prepared for this presentation.

Mar 1, 2010

By A Dix

Fire suppression systems are but one of the many technologies currently available to manage operational tunnel risks. However, the actual reasons for their use are often shrouded in mischievous discussions of the marketing variety.The international tunnelling community still stands divided on the merits (or otherwise) of fire suppression systems. For some the debate focuses on their cost compared to the theoretical benefits they bring to human safety.Long standing concerns about their potential adverse effects in an emergency are often at odds with the experience from tunnels which use them. High installation and operational costs are cited as reasons not to use them, yet toll road operators and insurers increasingly use them as a risk mitigation strategy for toll revenue protection.Fact or fiction, myth or reality, should such systems be seriously entertained or are they just another expensive gadget in the escalating array of expensive toys for modern tunnels? Ultimately this presentation argues that they have their place as a risk mitigation measure to achieve a range of objectives. The exact circumstances for their use ultimately fashioning their design and operational characteristics. This is an abstract only.&nbsp;No&nbsp;paper was prepared for this abstract.

Mar 8, 2011

By T. Shariff

Titanium alloys have found increasingly wide range of applications in aerospace, chemical, medical, sporting, power generation, oil and gas extraction industries mainly due to the low density, high mechanical property characteristics, biocompatibility, and excellent corrosion resistance. In the manufacturing routes of their finished products, welding has been a key technique used and always been a main concern requiring the stringent compliance to the well defined process. Conventionally, gas tungstenarc (TIG), gas metal-arc (MG), plasma arc, and electron beam welding processes have been used to weld titanium alloys. Nowadays, laser beam welding has provided great challenging applications for titanium alloys due to the low and precise heat input, deep and narrow fusion zone, small heataffected zone, low thermal distortion and high productivity. At the NRC Institute for Aerospace Research, some R&D work has been undertaken for titanium alloys using laser beam welding process. These investigations have mainly concentrated on optimizing the welding process as well as understanding the fundamental process-structure-property relationships. In this invited keynote presentation, the research progresses obtained and the main issues encountered in laser welding of titanium alloys will be briefly summarized.

Jan 1, 2011

By D. E. Larson

The U.S. Bureau of Mines investigated Fe-base alloys containing 8 pet Crwith Ni, AI, and Si additions as substitutes for standard AISI Type 304 stainless steel (SS) in high-temperature oxidizing applications. The objective of this study was to reduce the amount of Cr required to make an austenitic stainless steel while retaining satisfactory workability, mechanical properties, and oxidation resistance. Alloys prepared in this investigation had a composition of Fe-8Cr-lMn-0.07C with varying amounts of Ni, AI, and Si. A minimum of 10 pet Ni was required to achieve an austenitic composition. The microstructures of the austenitic alloys were very susceptible to room-temperature, deformation-induced martensitic transformations. When the alloys were cold worked or stressed, the materials had far greater tensile strengths than Type 304 SS at room temperature. At higher temperatures, tensile strengths and workability of several of the alloys were comparable to that of Type 304 SS. Although martensitic transformation caused the room-temperature properties of the experimental alloys to be quite different than those of Type 304 SS, the superior oxidation resistance and similar hot workability of several alloys encourage their use as replacements for Type 304 SS.

Jan 1, 1989

By R. D. Short

Environmental regulations for noise and air pollution are directly affecting the type of equipment and construction techniques being utilized for pile driving construction using diesel hammers in California and elsewhere. Consequently, the cost of construction is increasing and in some cases, the use of diesel pile hammers has been prohibited. Based on the trend in California and elsewhere in the world, environmental constraints are spreading and becoming more restrictive. The City of Tokyo, Japan, for example has banned the use of diesel hammers. Environmental restrictions on diesel hammers can be satisfied by using modern hammers, clean burning fuels, synthetic lubricants and pre-excavation techniques.

Jan 1, 1989

In any earth-moving operation, more profit may be earned or lost by equipment scheduling than by any other single facet of the project. Many now-defunct earth movers would have survived the cost-profit squeeze had they followed an efficient, cost saving, equipment scheduling program. The ideal program would have every item of the equipment fleet working all of the time. In practice this ideal situation is not possible. Several basic methods of equipment scheduling, with an infinite number of minor variations, are used. The first approach is the use of a "minimum equipment fleet," of which all items or equipment are scheduled each working shift.

Jan 10, 1967

By William E. Ford, Edward Salisbury Dana

Secondary Twinning. - When there is reason to believe that the twinning has been produced subsequently to the original formation of the crystal, or crystalline mass, as, for example, by pressure, it is said to be secondary. Thus the calcite grains of a crystalline limestone often show such secondary twinning lamella?. The same are occasionally observed (Ilc, 001) in pyroxene crystals. Further, the polysynthetic twinning of the triclinic feldspars is often secondary in origin. This subject is further discussed on a later page, where it is also explained that in certain cases twinning may be produced artificially in a crystal individual - e.g., in calcite (see Art. 282).

Jan 1, 1922

This bibliography lists publications issued by the Bureau of Mines concerned with investigations on petroleum and natural gas. The items included are chosen for their continuing interest and value. It was recognized early that a list of petroleum and natural gas publications was needed for the Bureau&apos;s work, and unofficial publication of a ?straight forward? listing was begun. It was at first a chronological list; however, suggestions submitted by its users prompted a format change to show publications under broad, general topics. Author and subject indexes were developed, becoming more detailed with each new edition. This present list supersedes the ones compiled in 1949, 1952, and 1957, and several supplements, which were aside available to the public by the Library Of the Bureau?s Bartlesville Petroleum Research Center. The unofficial field publication came to be widely known nail in considerable demand by those who are primarily interested in the Bureau&apos;s publications on petroleum and natural gas so that it became, desirable to have it published as an Information Circular. It is hoped drat, this official publications will result in a wider and more effective use of the Bureau&apos;s research results which are reported in its publications.

Jan 1, 1964

[THIS bibliography lists publications issued by the Bureau of Mines concerned with investigations on petroleum and natural gas. The items included are chosen for their continuing interest and value. It was recognized early that a list of petroleum and natural gas publications was needed for the Bureau&apos;s work, and unofficial publication of a ?straight forward listing? was begun. It was at first a chronological list; however, suggestions submitted by its users prompted a formed change to show publications under broad, general topics. Author and subject indexes were developed, becoming more detailed with each new edition. This present list supersedes the ones compiled in 1949, 1952, and 1957, and several supplements, which were aside available to the public by the Library Of the Bureau?s Bartlesville Petroleum Research Center. The unofficial field publication came to be widely known and in considerable demand by those who are primarily interested in the Bureau&apos;s publications on petroleum and natural gas so that it became, desirable to have it published as an Information Circular. It is hoped that this official publication will result in a wider and more effective use of the Bureau&apos;s research results which are reported in its publications.]

Jan 1, 1964

The past decade has seen revolutionary advances in communications and information-handling techniques which have been stimulated by &quot;cold war&quot; military requirements and by current programmes for probing into outer space. The tools used in exploration for petroleum and minerals have been improved significantly as a result of this new space age technology and even greater improvements are on the way.Two areas of technical activity have been particularly fruitful in enhancing the effectiveness of exploration methods. These are1. the development of new approaches, based on information theory,for extracting signal from noise more efficiently than before, and2. the use of high-speed digital computers for storing and processing all kinds of exploration information, not only geophysical but geological as well.In seismic prospecting, use of information theory has led to new techniques such as time-domain filtering, wave-number filtering and correlation methods which have made it possible to obtain usable reflection data from areas which were previously considered non reflective. Complex playback and other data processing facilities have been developed to apply these approaches.Digitization of geophysical data for handling by high-speed electronic computers facilitates many of these techniques for signal-to-noise improvement. Direct digital recording of seismic data in the field is now being d&apos;one on an experimental basis in the United States, and this should become a standard procedure, at least for problem areas.The increased dynamic range, flexibility of filtering and other data processing, and convenience of information storage and retrieval make digital recording attractive in spite of its high cost compared to conventional analogue methods. Digital computers are being programmed to carry out many operations in data reduction and interpretation with substantial savings in time and cost over conventional procedures.INTROPUCTIONIn the years that have passed since the end of the Second World War, the western world has witnessed a technological revolution which may be as far reaching in its ultimate impqct as the Industrial Revolution of the last century.

Jan 1, 1963

By James H. Snyder

This final report presents results of a program to develop a new conveyor system, adaptable to existing miners or loaders, which reduces the noise level to 90 dBA without reducing machine performance. The trial conveyor design consists of a main conveyor and a swinging tail conveyor. The main conveyor incorporates a rubber-covered return guide roller, rubber mounting of pillow blocks, rubber cover of the return bed, and a rubber belt running between the flight chain and the conveyor bed plate. Testing took place in a surface coal pit and underground at the Peabody Spur Mines in Boonville, Indiana. Noise Levels as low as 90 dSA were observed on the surface and 93/94 dRA underground. Recommendations for further work are also presented.

Jan 1, 1976

By Jorj Osterberg

550 load tests of up to 150 MN have been completed on driven and bored piles using the Osterberg Load Cell. Because the test measures side shear and end bearing separately, much can be learned about the forces on the pile as it is loaded to ultimate capacity. At working loads side shear almost always far exceeds end bearing, with the distribution of shear and bearing greatly affected by disturbance occurring during drilling operations. Since much less movement is required to mobilize side shear than end bearing, most of the bearing develops after the working load is exceeded. Thus with insufficient bottom cleaning, safety against excessive settlement can be considerably reduced. Improved methods of drilling, hole cleaning, rebar cage installation and concrete placement are discussed. For rock socket piles it has been found that the ultimate test load far exceeds the working loads in most cases. This is almost always due to greater penetration into the rock than is required for adequate safety against excessive settlement. Factors affecting rock socket capacity are discussed. Increase of side shear and ultimate capacity with time is discussed. Case histories for driven and bored piles in soil and rock sockets are described.

Jan 1, 2001

By J. I. Paige

The Bureau of Mines studied methods for recovering unreacted titanium minerals and petroleum coke from titanium chlorination plant wastes prior to neutralization treatment with lime. The objective was to recover valuable raw materials and to reduce the amount of waste materials that must be treated for disposal. Samples of solid wastes were physically beneficiated by gravity concentration (tabling) to recover titanium minerals containing 69.0 to 92.4 wt-pct Ti02 and by selective carbon flotation to recover petroleum coke containing 94.0 to 96.8 wt-pct C. Laboratory data indicate that the recovered titanium mineral would decrease the amount of solid waste to be disposed of from 32.8 to 53.9 wt-pct. The recovery of coke would further decrease the amount by additional 32.9 wt-pct. Preliminary tests conducted on recovering vanadium, chromium, and columbium from liquors obtained by leaching chlorination residues also have shown that (1) 97 pct of the vanadium was extracted from leach liquors in a two-stage solvent ex-traction procedure and (2) 58 pct of the columbium and 40 pct of the chromium were separated from the leach liquors by an ion exchange technique using a strong acid resin.

Jan 1, 1982

By Motohisa Kanda

The time and amplitude statistics necessary to adequately describe electromagnetic (FM) noise in mines are illustrated through computer software techniques. They are 1) Allan Variance Analyses (AVA), 2) Interpulse Spacing Distributions (ISD), 3) Pulse Duration Distributions (PDD), 4) Average Crossing Rates (ACR), and S) Amplitude Probability Distributions (APD). These statistics are illustrated using data taken from a rather large store of raw analog data recorded in operational mines. The curves generated for the illustrations characterize the noise environment in the mines from which the corresponding data were taken, and should aid in the design of reliable communication systems for such mines.

Jan 1, 1974

Australia has historically been a world leader in mining innovations. This trend is reflected in the international patent records, which show that in recent years there has been some recovery in the number of patent filings arising from Australian research. These innovations occur across a wide cross-section of mining technologies and derive from both public and private sector research. Australian mining innovations are largely dominated by new processes and equipment, principally in the areas of rock drilling and coring, strata stabilisation, cutting tools, blasting, mine design and oil field exploitation. They include improvements in drill bits, rock bolts and accessories and wellbore systems. Another area that has received significant research attention has been the in situ thermal processing of coal deposits. High profile examples of Australian mining innovations include the æSORDMinerÆ, a remote-controlled mining machine for use in mining collapsing wet environments, and CSIROÆs SMART*CUT rock cutting pick that dramatically increases the rate of cutting hard rock. This paper will provide an overview of recent innovations in Australian mining, as reflected in the international patent records, including the organisations and individuals active in the field, and the technological nature of specific innovations.

Jan 1, 2008