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By John Floyd, Larry Wardrip

A series of tests were conducted to evaluate the performance of a high density, high velocity cartridged explosive. The tests included two production blasts in a limestone quarry and two production blasts in a granite quarry. To quantify blast and product performance, each blast was monitored with the following equipment: l Two (16mm (Lo Cam) high speed cameras (500 images per second) l Velocity of detonation recorder (I million samples per second) l Four face motion accelerometers (1 million samples per second) l Digital seismograph The fragmentation distribution produced by each blast was quantified with digital image analysis The benefits of the use of high velocity, high density toe loading was quantified in terms of: l Vibration reduction l Fragmentation improvement l Excavator performance In addition to the field tests, a comprehensive evaluation was performed to determine the cost/benefit relationship of the use of the toe load. This paper will include the findings of the study along with guidelines for use in other quarry operations.

Jan 1, 2002

By R F. Johnston, I D. Sommerville

This paper presents an overview of the researches carried out in our laboratory on the application of plasma in recovery of alloy elements from waste slags and the treatment of lean ores, which are examples of advanced materials processing. After briefly reviewing the early work on the reduction of nickel, chromium, manganese, vanadium and titanium oxides, and a short investigation of the reduction of titanium oxide from the slag resulting from the blast furnace smelting of a titanomagnetite ore, the paper concentrates on the more recent studies on the reduction of an Australian scheelite. In some of these experiments, aluminium was used in addition to carbon as a reductant, in virtually all cases complete reduction was achieved within a relatively few minutes even with carbon alone during plasma processing. It therefore appears that this technique provides a possible processing route to facilitate the recovery of valuable alloying elements from non-traditional sources, or to permit process step elimination.

Jan 1, 2000

By OÆBrien D, Priddle D

In order to avoid costly moisture penalties on coal shipments and to minimise rail freight costs, screen bowl centrifuges were selected and installed in the Mount Thorley Coal Preparation Plant for dewatering fine coal product. The Mount Thorley fine coal circuit consists of desliming the -0.5 mm (ww) fine coal in two stages of classifying cyclones prior to recovery by froth flotation. Provision has been made to bypass the flotation circuit with the classified flotation feed reporting directly to product and the centrifuge dewatering circuit has been designed to handle either flotation feed or flotation product. Major mechanical failures of the gearboxes and the ceramic tiling occurred early in the operation life of the machines which led to design changes being made to achieve satisfactory operation. This paper discusses the operating experience at Mount Thorley with respect to both mechanical and metallurgical performance of the screen bowl centrifuges since their installation in 1985.

Jan 1, 1989

By W. F. Carew, F. A. Crossley

Tensile, creep-rupture, and stability tests were employed to evaluate the effect of a-strengthening and ß-complexing additions on the base composition Ti-6Al-3Mo. The ultimate objective was to produce an alloy of greater strength than the Ti-7A1-3Mo alloy. Strengthening of a was accomplished by additions of 2 and 4 pct Ge, 4 pct Sn, 4 pct Zr, and 2 pct Sn-2 pct Zr. Making the ß more complex while keeping the total of ß-stabilizing additions constant at 3 pct resulted in higher tensile strengths but lower creep and rwpture strengths, especially at 1000°F. None of the more complex versions of the base alloy offers greater promise than the Ti-7A1-3Mo alloy. However, some improvement in the strength of the latter may follow from additions of zirconium perhaps up to 4 pct. PREVIOUS work directed at the development of titanium-base alloys with: 1) minimum room-temperature tensile elongation of 10 pct in 1 in., 2) high creep resistance at elevated temperature, and 3) the ability to retain original room temperature tensile ductility following exposure to creep conditions at elevated temperatures, demonstrated Ti-Al-Mo ternary compositions in the range 5 to 7 pct Al-3 to 6 pct Mo to be the most promising. Of this group the Ti-7Al-3Mo alloy was the strongest.'-= The objective of the present work was to determine if alloys of this type could be further strengthened by making additions which dissolve preferentially in the a-phase and by making the ß-phase more complex. For this study the base composition Ti-6Al-3Mo was selected rather than Ti-7Al-3Mo in order to minimize the possibility that in a more complex alloy with a-strengthening additions, low ductility might obscure the strength contribution. The metals

Jan 1, 1959

In June 1992, the High Court of Australia recognised native title of the Meriam people over parts of the Mer Island in the Torres Strait as a form of common law. The Court also indicated that native title may have survived European settlement of the mainland Australia where it had not been extinguished by Governments and Aboriginal people have maintained their traditional connection with the land. The decision meant that two systems of land law were seen as existing side by side in Australia: ò one which derived from grants from the Crown under laws passed by Parliament; ò another which derived from the diverse laws and customs of the many Aboriginal groups in Australia.

Jan 1, 1996

By Harold H. Goe, Louis V. Bender

The recovery of arsenic was started at the Washoe Reduction Works (later called the Anaconda Reduction Works) in 1904, when an arsenic plant was constructed adjacent to the lower end of the 60-ft. main flue.' This plant originally consisted of a Brunton roasting furnace for treatment of flue dust and a small reverberatory furnace for treating the crude arsenic produced in the roasting operations, together with the necessary kitchens for condensation of the fumes and grinding and barreling apparatus for preparing the refined white arsenic for market. The Brunton furnace was fired with wood. It was 14 ft. 6 in. in diameter with two outside fireboxes. The hearth revolved upon a central shaft. The charge was fed through a dust-tight hopper on to the center of the hearth and slowly moved to the outer edge of three rows of stationary rabbles fastened in the roof of the furnace. There was a 3-ft. space between the hearth and roof. A crude arsenic was condensed from this furnace. The hot flame from the fireboxes passed directly over the charge, vaporizing the As203 that was carried through brick flues to the condensing chamber. This chamber was 8 ft. high, 16 ft. wide and 240 ft. long, divided into small kitchens by partitions spaced every 7 ft. It was connected with the main flue system to provide draft and to receive any losses from the chamber. The small kitchens were connected by openings in such a way that the fumes took a zigzag course, causing them to come in contact with the cold walls and ceiling and condense the arsenic. There was an opening from the outside into each kitchen, for the removal of the deposited arsenic, which was closed by a wooden door. The refining furnace was a small coke-fired reverberatory having a hearth 10 by 20 ft. in dimensions. It had three hoppers through which the crude charge was introduced, and one firebox placed at one end. The hot gas from the burning coke passed over the charge, volatilizing the arsenic and carrying it to the kitchens.

Jan 1, 1934

By James Paul

BEGINNING in December, 1933, and continuing to the close of April, 1934, large sums of money were expended in the states of Pennsylvania, Ohio and West Virginia through the conduct of Federal and State Civil Works Administration, financed by the Government as a part of the President's recovery program to furnish employment to mine employees idle as a result of the economic depression. PURPOSE OF THE PROJECT The protection of the public health against the pollution of public water supply by acid mine drainage was the incentive that prompted the request that the sealing of abandoned bituminous coal mines be made a Federal project. A paper before the Central Section of the American Water Works Association, Wheeling, W. Va., on Aug. 24, by E. S. Tisdale, Chief Engineer of the West Virginia Department of Health, tersely says: In October, 1933, the combined experience of the U. S. Bureau of Mines and the U. S. Public Health Service and the States of Pennsylvania, Ohio, West Virginia and Kentucky resulted in a report being filed in Washington, first with the Public Works Administration and later with the Civil Works Administration, where it was favorably acted upon, calling for these governmental agencies under the direction of the U. S. Public Health Service to expend $1,500,000 in a unified effort to seal abandoned coal mines in Pennsylvania, Ohio, West Virginia, Kentucky and six other states farther down along the Ohio river. The report referred to was embodied in a petition that was signed by the chief engineers of the State Departments of Health of the several states contiguous to the drainage area of the Ohio River. The project as established under Federal supervision became interstate with respect to the several states involved, and upon the termination of the Federal project on Feb. 15, it was authorized as a State C.W.A. project, effective Feb. 20, under the supervision of the State Departments of Health and the State C.W.A. Administration, which continued to March 29, and was succeeded by the S.E.R.B. of the R.W.D. from April 2 to April

Jan 1, 1935

Book review Burkin, A. R. (ed.) . Leaching and reduction in hydrometallurgy. London, Institution of Mining and Metallurgy, 1975. £10. hydroxide pyritearsenopyrite NIM reports Report no. 845 A n electron-microprobe study of the nickel distribution in a serpentinite from Volspruit, Potgietersrus. (22nd Oct., 1969; re-issued Dec. 1975). Report no. 1546 Pilot-plant smelting campaign on iron ores from Tete. (22nd May, 1973; re-issued Jun. 1976). Report no. 1557 Cost estimates for the production of pig iron in the Tete district of Mocambique. (18th Jun., 1973; re-issued Jun. 1976). Report no. 1600 Dilute-acid leaching of slag from Tete ore. (20th Nov., 1973; re-issued Jun. 1976). Report no. 1602 The roasting of Tete slag for the extraction of vanadium. (20th Nov., 1973; re-issued Jun. 1976). Report no. 1635 Magnetic separation tests on Tete slag and ore. (30th Apr., 1974; re-issued Jun. 1976). Report no. 1671 Pyrometallurgical retreatment of a slag for the recovery of vanadium. (11th Oct., 1974; re-issued Jun. 1976). Report no. 1785 Some thermodynamic aspects of systems relevant to the flotation of sphalerite. Report no. 1808 Spectrophotometric determination (with pyrocatechol violet as chromogenic agent) of aluminium in zirconium metal and in the residue from anodesludges. Report no. 1813 The economic potential of some pegmatites from the Kenhardt area in relation to the trace-element content of their border zones. Report no. 1817 The rapid determination by X -ray-fluorescence spectrometry of tungsten in tungsten ores and concentrates. Report no. 1820 The thermodynamics of the formation of chlorocomplexes of iron (III), cobalt (II), iron (II), manganese (II), and copper (II) in erchlorate medium.

Jan 8, 1976

Over the last thirty years production of heavy minerals from Australian deposits has dominated the world market. The main incentive has been to suoply the raw material for titanium dioxide based pigments. These ~ninerals include ilmenite, rutile, leticoxene and more recently, synthetic rutile. Inevitably the viabilit/ of developing placer type deposits has seen influenced by other heavy minerals present, such as zircon and monazite, but these have been of secondary importance. For most of the sixties and seventies, Australia supplied the 'najority of free world rutile and zircon, and a large proportion of the ilmenite. With the run-down of rutile- rich reserves in eastern Australia, the emphasis has s:iifted in several countries, including Australia, to fill }the gap with i l Wen i to and its derivatives, leucoxene, synthetic rutile and titanium rich slag. over the next 15 - 20 years, as high grade beach placers in Western Australia are mined out, less traditional sources for mineral sands products will be opened up. Low grade placers (particularly those dominated by ilmenite) will be reassessed in Australia, U.S.A., Africa and Asia, and exploration will shift from beach and dune environment, to heavy mineral concentrations in alluvials, lake deposits and continental shelf deposits. At the same time, production of anatase and bastnaesite will be expanded, as required, from the huge resources contained in carbonatites in 3razil, U.S.A. and China.

Jan 1, 1986

By D. Royston

Reducing SAG Mill feed size has been a major trend in recent years. ‘Mine to mill’ strategies have reduced blasted-rock size, and in a growing number of operations reducing the primary crusher CSS and/or adding additional crushing upstream of the SAG mill have reduced rock feed size. While reducing feed size will increase SAG mill throughput, issues arise in terms of retaining charge in the mill, exposing the shell lining to impact damage, and maintaining milling performance should the pre-crush system shut down. This paper reviews the past experience on pre-crushing for SAG mills and provides an analysis of liner design (in particular grates and shell liners) for pre-crushed feed.

Jan 1, 2012

Green policies have gained momentum since the 1972 Stockholm Environment Conference. The environmental movement has influenced political initiatives both in New Zealand and abroad. Governments and international institutions have addressed local, regional and global environmental issues with varying degrees of success. New Zealand so far has not supported the United Nations' call for sustainable development in a,consistent manner.New institutions and new rules for resource management mean there are opportunities to look after the land in different and more ecologically sensitive ways than has happened in the past.The increasing influence of regional councils in resource management planning will have important implications for mining and mineral exploration. These trends are discussed and possible future events outlined.

Jan 1, 1990

By Russell J

A sustained drop in the grade of Mount Isa lead-zinc-silver ore occurred in mid 1980. It was decided to increase concentrator throughput from 200 000 to 240 000 tonnes/four week period to maintain budget metal production. To achieve this increase whilst maintaining acceptable grinding and flotation performance, crushing plant final product size had to be reduced from 100%-13mm to 1000-11.2mm. The goal in the crushing plant was to achieve a 20% increase in throughput with a 20% decrease in the top size of the product. This was achieved by operational changes to improve plant availability and optimisation of the existing crushing and screening equipment Performance.

Jan 1, 1978

By J. M. Mutmansky

The objective of this study was to produce coal dusts for laboratory research that are similar to mine airborne dusts in chemical, mineral, and physical characteristics. In this investigation, dusts produced in laboratory comminution equipment were compared with continuous-miner-generated dust for similarity in physical characteristics. Mining-generated dust (MGD) and bulk coal samples were first collected from an underground mining operation. The bulk samples were then processed in the laboratory for size reduction in various comminution devices. These laboratory-generated dust (LGD) samples were subjected to size and microscopic analyses. Physical properties of the dust particles were studied on a scanning electron microscope (SEM). A numerical shape coordinate system (SCS) was also developed and applied to 300 particles from each sample. Statistical analysis was then performed on the collected data and characteristics of the MGD and LGD samples were compared.

Jan 1, 1995

By Scherbatsky VB, zon BM, Babushkin NM, Kitaev BI, Shabel&apos

The structure and hydrodynamics of the raceway zone of a blast furnace was studied on a cold model representing a sector containing two tuyeres. The model differed from the usual in that it was prov- ided with continuous flow of the coke layer at pre- determined rates, had provision for changing the tuyere parameters (diameter, protrusion, inclinat- ion) and irrigation of the layer with liquid. A combination probe was developed which per- mitted simultaneous measurement of the pressure field both across the area and through the height of the layer as well as determining the topography of the raceway. The velocity fields in the layer were measured with a specially made impulse thermo- anemometer. The determining criteria of the model were taken as the relationships between the energy of the blast and the particles, the dimensions of the raceway and the cross-section of the tuyere. The model established the effects of the tuy- ere structural parameters, blast parameters and amount of liquid products of smelting on the con- figuration of the raceway, the structure of the layer, pressure and velocity fields in the vicinity of the tuyeres and in the vertical direction through the layer. The properties of the raceway formation and the structure of the layer in motion have been clarified.

Jan 1, 1981

By P. Dosmond

In ore mining technology, the loading and hauling operations are undoubtedly the area where the most spectacular progress has been made during the last twenty years. In the iron ore mines of Eastern France production of 62 million tons for 1962 and 19863 constitute a worthwhile experience worldwide. These deposits which are located in Lorraine are of sedimentary origin and they contain many mineralized horizons with workable seams varying in depth from 330 to 830 ft.

Jan 1, 1970

By D. O. Kennedy

THIS CHAPTER on minor nonmetals covers greensand, meerschaum, mineral wool, and wollastonite. Mineral wool was by far the most valuable material among these minor nonmetals reported in the United States in 1956. GREENSAND Output of greensand (glauconite) declined in 1956. The Kaylorite Corp., Dunkirk, Md., and the Inversand Co., Sewell, N. J., were the only firms that reported production of this commodity. Output came from open pits in Calvert County, Md., and Gloucester County, N.J.

Jan 1, 1958

[NOTE.-The following discussions of papers contained in this volume are printed without regard to order of succession. It has been impracticable to secure from the various parties, corrected reports of their contributions in time to effect any particular desired arrangement in this respect. The papers of Messrs. Pourcel, Osmond and Sauveur, were considered at Chicago together with others of cognate character ; and the whole discussion will be found in vol. xxiii., under the head, " Physics of Steel."]

Jan 1, 1894

Until the early 1960s the world aluminium industry was dominated by six principle pro- ducers with integrated activities from bauxite mining to aluminium production. The growth in consumption of aluminium since that time and the emergence of additional producers has broadened the market for bauxite. In addition the increase in the optimum size of alumina refin- eries has influenced competing metal producers to unite in large joint ventures to minimize alumina costs. From these bases the paper examines present and likely future markets for Australian bauxite; differing marketing phil- osophies for serving those markets; factors influencing successful marketing; and the sources and relative strength of competition which Australia faces.

Jan 1, 1974

By Charles L. Kimbell

The series summarizing the prices of the major nonferrous metals on the stock exchanges of the United States and the United Kingdom has been continued this year in tables 23 and 24. Time constraints have prohibited preparation of other price information that has appeared in this study in previous years. Users are urged to consult the 1993 USBM publication Metal Prices in the United States through 1991, which gives an analysis of historical price series and trends, or the 1993 edition of Mineral Commodity Summaries for current U.S. prices on non fuel commodities, and to utilize U.S. Department of Energy sources for information on fuel material costs.

Jan 1, 1993

By H. Tanner, T. Heikkinen

In1950 studies concerning mining and milling of the approximately 17 million tons of ore remaining at Outokumpu revealed the surface facilities for economical treatment were inadequate. The two shafts would soon be too far from the mine workings. Moreover, in spite of several extensions, mill capacity was insufficient and recoveries were not satisfactory. Therefore it was decided in 1951 to sink a new shaft and to build a new mill and auxiliary surface buildings around the shaft. The new shaft was sunk near the center of the remaining orebody, about 650 ft from the ore to the footwall side. This location placed the main part of the shaft as well as the crusher rooms and the ore bins around the lower end of the shaft in the firm and strong mica-schist.

Jul 1, 1955