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The Framework Convention on Climate Change (FCCC) places serious obligations on New Zealand as a signatory nation. This paper examines the nature of the FCCC, New Zealand 's proposed policy response, and the.implications for the minerals industry.

Jan 1, 1994

By B. H. Clemmons, B. G. Saunders, R. H. Stacy

"INTRODUCTION This investigation was undertaken to determine the response of Birmingham (Alabama) red-iron ore to heavy-medium concentration. Specifically, the work involved a study of the efficiency of the process in separating coarse gangue diluents from the ore and an endeavor to evaluate the potential economic results. The investigative work was not intended, nor is it to be construed, to be adequately exhaustive in scope to enable immediate plant construction. Rather, the primary objective was to determine the grade of ore that could be produced by heavy-medium treatment and the resulting indicative or tentative benefits to be derived from such treatment. The latter, in turn, would determine the merits of the more exhaustive study that would be required for an ultimate decision on the heavy-medium treatment of the ores.The problem of avoiding excessive contamination of red-iron ores by shale and/or ferruginous sandstone has been before the operators of the iron mining industry of the Birmingham, Alabama, district for many years. Within the last two decades, increased mechanization of mining methods has increased this contamination to a considerable degree. In fact, general utilization of scraper loading and other mechanical methods of mining, in conjunction with small increases in the natural insoluble content of the ores, in some cases has actually resulted in the production of ""acid"" or excessively insoluble ore, where ""basic"" or excessively lime ores were produced formerly.The contaminating materials are derived largely from roof spells and natural parting seams in the ore, a condition that to some extent has been aggravated by the irregularity of the ore beds. The latter have been subjected to both primary and secondary folding in many places. Considerable faulting has taken place, also. In many localities these conditions render virtually impossible complete avoidance of ore contamination from the over and underlying sandstones and shales. However, in a few localities, where the ore beds are less disturbed and shale partings are absent, mining can and is being accomplished with relatively little dilution."

May 1, 1948

By W. M. Shaver, R. Letourneau, W. R. Dengler

Dynatec Mining Ltd. contracted to sink a 1500-m (4920 ft) concrete-lined shaft for Falconbridge Nickel Mines in Sudbury, Ontario, Canada. The shaft has an inside diameter of 6.3 m (20.5 ft) and is equipped with steel furnishings. Dynatec used the owner-supplied, 4.6-m (15.1 ft) diam, double-drum hoist to sink the shaft. For muck removal, 12.5¬t (13.8-st) buckets were used. The capacity of the concrete-¬placement buckets was 4.6 m3 (162.4 ft3). One of the unique features of the shaft sinking operation was the use of a two-¬boom, electric-hydraulic drill jumbo permanently mounted in the shaft sinking stage. An in-the-hole (ITH) drill was used to drill a 200-mm (8-in.) cut hole for the 4.8-m (16 ft), full face rounds. This paper describes the performance obtained with the electric-hydraulic drilling equipment and the high-capacity muck removal and concreting equipment.

Jan 1, 1994

By Robert T. Langland

The Bureau of Mines, at its Denver, Colo., research center, has developed a computer program to solve nonlinear regression problems. The program is written in a general form so that, regardless of the functional relationship assumed, the unknown parameters may be evaluated by the Newton-Raphson method of iteration. Variances and covariances of the parameters are derived, based on the propagation of errors. A creep function is established from shale test data as an example of program utility. Program accuracy is compared to the accuracies of other programs in present day use.

Jan 1, 1974

By THOMAS J. CLIFFORD

IN 1926, finer grinding began to be a feature of the milling practice of the Southeast Missouri lead district. Nothing since the adoption of flotation has caused greater changes and greater improvement in results. The trend toward finer grinding, with the consequent discarding of tailing at finer sizes, and consequent lower assays in lead, continued to progress until 1931, when the abnormally low price of lead brought a halt: that is, the better metallurgical results obtained would not offset the increased costs due to higher power and necessary maintenance. Since 1931 a slight tendency toward the discard of coarser tailing has taken place. , In 1926, larger rod mills i.12 ft. 1 in. by 6 ft. 6 in.) than any previously used in the district were installed in cue plant, and a new primary crushing plant, of greater capacity was built. This combination demonstrated immediately the better metallurgical results obtainable by finer grinding and all the mills now running have adopted the practice.

Jan 1, 1934

By Kumar Vikram

Rich reserve of prime quality limestone in east khasi hills of India and abundant quantity of low-cost fuel (Natural Gas) in Bangladesh made Lafarge Surma cement limited a joint venture company of Lafarge France and Cementos Molins Spain to envisage an integrated cement plant at Chatak District-Sylhet) a bordering town of Bangladesh. Since April 2006 the single flight 17 km Long Belt Conveyor (LBC) built by M/S Larsen & Toubro Ltd. (L&T), ECC Division an engineering and construction company of India, is feeding limestone/shale to the Lafarge Surma cement plant. This engineering marvel was created on a turnkey basis with technology support of M/S Aumund France

Jan 1, 2008

By Robert D. Thomson

Sheet mica is an important material in the manufacture of electronic and electrical equipment. Large quantities are consumed each year as an essential component in generators, transformers, radios, television sets, radar, electric lighting equipment, and electrical appliances. The nature, structural imperfections, and impurities determine to a great degree the usefulness of sheet mica. Proper processing and classification add greatly to its market value. This report is designed to assist producers in understanding the complexities of marketing muscovite sheet mica. ACKNOWLEDGMENTS Special acknowledgment is due S. A. Montague, of Spruce Pine Mica Co. and G. A. Purcell, mica consultant, General Services Administration, for their critical review and many helpful suggestions in the preparation of thin report. Assistance from other industry and Government representatives is acknowledged with thanks.

Jan 1, 1955

By C. H. Ash

"The Red Chris Cu-Au deposit (522.7 Mt at 0.35% Cu and 0.27 g/t Au), northwestern British Columbia, is one of several pre-accretionary porphyry systems in the Cordillera of westernCanada. It is hosted by an Early Jurassic hornblende monzonite to quartz monzodiorite porphyry which forms part of a suite of dikes and stocks that intrude Late Triassic volcanic strata. Major and trace element chemical data suggest that these Early Jurassic intrusions have compositions which fall on the boundary between alkalic and calc-alkalic compositions. Alteration and mineralization in the Red Chris deposit are more typical of calc-alkaline porphyry systems with abundant potassic, sericitic and argillic assemblages and quartz-rich stockworks. It lacks Na- and Ca-bearing silicate assemblages which characterize the alkalic porphyry deposits of British Columbia. One of the more unusual features of the deposit is the abundance of carbonate alteration and veins which occur throughout the hydrothermal history of the deposit. This type of alteration and veining is more typical of alkalic porphyry deposits.The composition of the carbonates vary both temporally and spatially with different alteration zones. Potassic zones, which are characterized by orthoclase±albite±quartz±chalcopyrite±bor-nite±magnetite±hematite and Au/Cu ratios of 1:1 (g/t Au:% Cu), contain minor siderite veins and alteration. Quartz-sericite-carbonate (QSC) zones overprint earlier potassic alteration and comprisequartz+ankerite+sericite+pyrite+chalcopyrite with Au/Cu ratios of 0.5:1 (g/t Au:% Cu). Ankerite isthe main carbonate in this stage but has a variable composition with a more Fe-rich variety associated with mineralized veins. Localized chlorite-carbonate alteration zones, characterized by chlorite+carbonate+quartz±kaolinite±pyrite±gypsum and high Au/Cu ratios [2 to 3.5:1; (g/t Au:% Cu)],contain predominantly calcite. Late stage carbonate-gypsum veins have an ankerite to dolomite com-position which is very similar to the regional carbonate alteration and veins."

Jan 1, 1997

By Herbert Clark Hoover, Lou Henry Hoover

GEORGIUS AGRICOLA was not only the author of works on Mining and allied subjects, usually asso ciated with his name, but he also interested himself to some extent in political and religious subjects. For convenience in discussion we may, therefore, divide his writings on the broad lines of (1) works on mining, geology, mineralogy, and allied subjects; (2) works on other subjects, medical, religious, critical, political, and historical. In respect especially to the first division, and partially with regard to the others, we find three principal cases : (a) Works which can be authenticated in European libraries today ; (b) references to editions of these in bibliographies, catalogues, etc., which we have been unable to authenticate ; and (c) references to works either unpublished or lost. The following are the short titles of all of the published works which we have been able to find on the subjects allied to mining, arranged according to their present importance :-De Re Metallica, first edition, 1556; De Natura Fossilium, first edition, 15,46 ; De Ortu et Causis Subterraneorum, first edition, 1546; Bermannus, first edition, 1530 ; Rerum Metallicarum Interpretatio, first edition, 1546; De Mensuris et Ponderibus, first edition, 1533; De Precio Metallorum et Monetis, first edition, 1550 ; De Veteribus et Novis Metallis, first edition, 1546; De Natura eorum quae Effluunt ex Terra, first edition, 1546 ; De Animantibus Subterraneis, first edition, 1549. Of the " lost " or unpublished works, on which there is some evidence, the following are the most important:-De Metallicis et Machinis, De Ortu Metallorum Defensio ad Jacobum Scheckium, De Jure et Legibus Metallicis, De Varia Temperie sive Constitutione Aeris, De Terrae Motu, and Commentariorum, Libri VI. The known published works upon other subjects are as follows:-Latin Grammar, first edition, 1520; Two Religious Tracts, first edition, 1522; Galen (Joint Revision of Greek Text), first edition, 1525 ; De Bello adversus Turcam, first edition, 1528 ; De Peste, first edition, 1554. The lost or partially completed works on subjects unrelated to mining, of which some trace has been found, are:-De Medicatis Fontibus, De Putre¬dine solidas Partes, etc., Castigationes in Hippocratem, Typographia Mysnae et Toringiae, De Traditionibus Apostolicis, Oratio de rebus gestis Ernesti et Alberti, Ducum Saxoniae.

Jan 1, 1950

By Richard D. Short

The Pseudo Static Pile Load Test, PLT, is a rapid method for determining pile capacity. Pile design is usually based on theoretical calculations of ultimate load capacity using soil data from a field investigation. The pile capacity is confirmed during construction by analysis of blow counts using dynamic formulae, dynamic pile monitoring, and load testing. Load testing is the most direct and reliable method of determining the actual capacity of a pile. Conventional load testing procedures, however, are time consuming and expensive. A typical load test requires installation of two to four reaction piles, construction of a high-capacity steel test frame, hydraulic jacks, and dial gauges, and will typically take one to three days per pile. Costs for load tests range from $10,000 to $20,000 per test. The Pile Load Test machine features a 25-tonne weight mounted on a mobile test frame. PLT load tests can be performed in a matter of minutes once the equipment has been mobilized to the site. This paper examines three test sites where the PLT test method was used and compares the results to conventional load test results and theoretical capacity calculations.

Jan 1, 2000

By G. M. Potter, J. B. Rosenbaum, Masami Hayashi

Most Japanese copper smelters are located in areas of concentrated industrial activity and high levels of atmospheric pollution. A review of unofficial sulfur dioxide emission control data from major Japanese smelters shows capture of 91 to 99.7 percent of the sulfur in the smelter feed. The bulk of Japanese smel ting capacity was constructed in the last 10 years. Six of the major sme lters use flash furnaces, and two use reverberatory furnaces. A prototype three-furnace continuous system is in use as a parallel train with reverberatory furnaces at one smelter. Most of the sulfur dioxide is manufactured into sulfuric acid. The remainder is captured by gas scrubbers that yield gypsum and sodium salts. Ready markets exist in Japan for the acid and other su lfur byproduc ts.

Jan 1, 1967

By Lulie H. Crump

Salient information on reserves, production, and consumption of fuels and energy by State is summarized in this Bureau of Mines publication. Reserve and production data are shown for each of the fossil fuels (coal, crude oil, natural gas liquids, and natural gas) and for uranium. The consumption data of each of the major consuming sectors (household-commercial, industrial, transportation, electric power, and miscellaneous) are broken down by energy source (coal, petroleum, natural gas, hydropower, and nuclear). In addition, total energy consumption in the Nation in 1974 is compared with consumption in 1973 and 1975 (preliminary data).

Jan 1, 1977

By Luis W. Pommier

The wastes of the plating industry are generated in the process of rinsing the plated objects and during the cleaning of the plating shops. High volumes of hazardous waters are neutralized on site producing recyclable water, generating a metal rich, hazardous, filter cake. Occasionally, a complete plating bath has to be discarded which increases the metal content of the filter cakes. These filter cakes are discarded as hazardous at a cost of over $ 250 per ton. The metals found in the cakes are generally copper, nickel and chromium or zinc, lead and cadmium, assaying from 2% to 15% or even higher content of each metal The metals and their contents are highly variable. Some plating shops discard their products directly to hazardous waste sites, others, have them collected by companies which consolidate wastes from several producers prior to discarding. These wastes, richer in metal content than mine ores, need neither mining nor crushing and grinding for concentration. The commonly found impurities in the mine ores, i.e.: pyrites, arsenic, and valuable metals which are present in minute quantities, are absent in the filter cakes. The processes available to selectively recover the metals from the filter cakes, are discussed based on their technical and economic merits. The flow-sheets include leaching, solvent extraction when required, and electrolytic refining. Examples, showing the separation of copper, nickel and chromium and also of zinc and lead in pilot plants, show the technical and economic viability of the processes.

Jan 1, 1996

The closure of the only professional mining school in New Zealand will mean that the minerals industry will have to explore other options to fill their mining professional positions. Globally mining is not seen as an attractive career option for young people and recruitment into mining courses is at a low level. Yet industry demands ever increasing competencies with respect to technology, environmental issues and legislation. This paper addresses this issue by first discussing the attributes required of graduate mining professionals. It then looks at alternative ways on how these can be met internationally and on the home front.

Jan 1, 1997

By Kenneth B. Higbie

METALLURGICAL ACTIVITY in 1963 was again dominated by the insatiate demands of research and development conducted in conjunction with the nation's defense and aerospace programs. An increasing effort was noticeable throughout the year, however, to apply to the commercial field many of the processes and techniques that have been developed by government-sponsored research. Particularly effective has been the Industrial Applications Program of the National Aeronautic and Space Agency through which many of the technological advancements made during the course of NASA research and development have been published and released to the public. POWDER TECHNOLOGY Powder metallurgy techniques for fabricating metals, not long ago declared outmoded because of improved casting and shaping methods, have since made an astonishing comeback. Traditionally mechanical pressing of powder shapes has been employed when melting and casting was difficult or impossible, when phase relationships needed to be sidestepped, or when machining costs could be avoided. Hence, it has long been used for producing relatively small special shapes of high-melting metals and alloys. Small iron parts produced with a punch and die have been common for many years, but powder metallurgy techniques are now applicable to a wide range of materials and items. Hard-to-handle materials including refractory metals and their alloys are now rolled, forged, or extruded from billets made by sintering isostatically compacted powders. The major element of the powder metallurgy industry still comprises iron shapes, however, and two-thirds of the annual 100,000 tons of powder metallurgy products are made of iron. The largest single user of powder-forming techniques is the automobile industry which currently consumes 14,000 to 16,000 tons of iron powder per year. A typical 1963 model auto contained more than 100 pressed powder parts (e.g., transmission gears, timing gears, sprockets, ball joint suspensions) totaling 5 to 7 pounds per car. Some of these powders are used in self-lubricating parts of porous copper and copper alloys containing as much as 20 volume-percent lubricating oil. The expanded use of powder techniques, coupled with

Jan 1, 1964

By M. Bouchard, B. Cadieux et F. Goutier

Five phases of ice movement were r es pons ible f or glacial dispersion in t he study area. I ce fl ow directi on changed prog r es s ively from SE to SSW and then to the S. All observed glacial sed iments are associated with a south-southwest to south movement; t hey are grouped, on the basis of their texture, structure, morphology and composition, into four distinct lithofacies. A lithological study of the coarse-grained fraction (4-128 mm) of these lithofacies shows systematic compositional differences. These are: 1) variations in the proportions of local bed rock fragments; 2) variations in the horizontal displacement of the maximum abundance peak of a given lithology relative to its source area, and 3) variations in the length of dispersion trains associated with each lithofacies. Although dispersal trains can obviously be mapped without differentiating li thofacies, studies based on the consideration of lithofacies should give more reliable results than conventional methods.

Jan 1, 1984

By G. A. Christie

This paper presents a vision system capable of providing an accurate estimate for the volume of stockpiles using 2D images. By imaging a stockpile from multiple viewpoints with a two-camera system, a 3D point cloud of known scale is generated using image-based 3D reconstructions. With a small amount of user interaction, the points that correspond to the surface of the stockpile are extracted and used to measure the volume. The hardware required for the two-camera system is light enough to be carried by a small unmanned aircraft and is a cheaper alternative to LiDAR while still being competitive in terms of accuracy. When testing the volume measurement algorithm on a stockpile of known volume, the measured output was found to have less than a 3% error from the ground truth.

By D J. Black

The process of longwall coal extraction coal causes fractures in the overlying and underlying strata and these fractures become pathways for gas released from adjacent coal seams to flow into the mine workings and contaminate the ventilation air. If the rate of gas emission exceeds the diluting capacity of the ventilation air, the gas concentration will increase and exceed the statutory limit resulting in production delays.All potential gas sources within the planned mining area, including coal seams located above and below the working seam, should be identified and sufficient gas data collected and used to determine the specific gas emission from each gas source. Gas reservoir and emission modelling is recommended to determine specific gas emission and changes in gas emission from individual sources over the planned mining area. Accurate gas reservoir and emission modelling provides the information required to accurately design gas drainage programs to effectively manage gas emissions and minimise the risk of ‘gas-outs’.Given the increasing occurrence of incidents of gas concentration in ventilation air exceeding the 2.0 per cent statutory limit and changes to mine plans to avoid ‘difficult-to-drain’ areas, it is apparent that many operations are not effectively utilising gas reservoir and emission modelling to identify high gas emission areas and are not completing sufficient gas drainage in advance of planned mining.The process of gas reservoir and emission modelling to support gas drainage design to control tailgate gas concentration and fugitive emissions is presented and discussed.CITATION:Black, D J, 2017. Gas reservoir and emission modelling to evaluate gas drainage to control tailgate gas concentration and fugitive emissions, in Proceedings Australian Mine Vent Conference 2017, pp 65–72 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

By D. H. Platt

Bauxite, the principal source of aluminum, has been mined from deposits in Saline and Pulaski Counties, Ark., since 1899; war needs have greatly stimulated production. Many of the ore deposits are basin-shaped and either outcrop or are covered by a shallow-depth overburden at their peripheries; these are mined by stripping and open-pit methods. When stripping becomes economically impracticable, incline shafts or slopes are sunk on the dips of the deposits, and underground mining is done on the retreat, using a room-and-pillar method.

Jan 1, 1945

By Ewan Alexander

"As human beings, we have managed risk since the dawn of the ages and have been adept at doing so. In order to survive, we hunted or gathered. If we did not take enough risk, we died. If we took much risk, we died (Fig. 1). As individuals and tribes, risk had to be optimized to maximize our chances to thrive, as individuals and as tribes.In today’s world, the risks are vastly different, but in order to thrive, these must be managed. And no industry knows this as much as mining. In fact, the International Council of Mining & Metals (ICMM) has proposed the Critical Risk Model (Fig. 2) as a means of identifying critical risk, critical controls and associated performance standards. The ICMM focuses on sustainable development performance in the mining and metals industry. It has 23 members, representing some of the largest mining companies in the world.This approach is going to help the mining industry. But it must be applied effectively, with the acknowledgment that the system alone cannot be effective. We can say this confidently, as even companies known for the strength of their risk and safety management systems continue to experience significant incidents, and, in some cases, catastrophes. Why does that happen when all safety metrics, including injury rate, are pointing in the right direction? In the view of the author, it is only when leadership, culture and systems work in complete harmony that the resilience of an organization to manage its significant risk is at an optimal level. It remains an ongoing leadership challenge to maintain that balance and the optimal mindset in the organization. So how do you maintain that special balance?Let’s start with a basic premise. Leadership, supported by simple effective systems, creates culture which creates outcomes. Everyone going home safely is an outcome, as is cost effective operations, and to achieve those outcomes efficiently, the organization must focus on the inputs. And those inputs include effective leadership, effective systems (for the purposes of this article, risk and health, safety and environment (HSE) systems), good planning, stable operations and competent workers. This article will focus on gaining maximum performance from your risk management system."

Oct 1, 2016