Search Documents

The Sydney Coalfield, Nova Scotia contains extensive undersea longwall mining operations which are expected to continue well into the 21st Century. A long term research program has been initiated by the Cape Breton Coal Research Laboratory to investigate the full spectrum of problems associated with undersea mining and develop specific guidelines for use by the mine operator. At present, research is centred on the detailed evaluation of existing undersea sub- sidence guidelines, the identification and development of instrumentation capable of moni- toring seafloor subsidence profiles and the effective sealing of offshore exploration boreholes. In addition, work is also planned to examine in situ strata permeability changes occurring between the mining horizon and seabed and the feasibility of using artificial islands.

Jan 1, 1986

SINCE 1900, five underground fires of consequence have beenrecorded in the Broken Hill mines. These occurred at the Junction(1906), Proprietary (1906 and 1916), Block 14 (1906), and Centralmines (1923). All have been extinguished, but at an enormouscost; e.g., in the eleven months following on the 1923 Central mine fire the sum of £187,123 was expended in fire-fighting operations.To this series may be added others, as the South (1925) and British mine (1918) fires, which were extinguished before serious damage had resulted. All, however, have occurred within a period of 28 years, and in a district where spontaneous combustion, a prolific source of fire in the U.S.A., has been practically nonexistent. Therefore, definite fire risks exist in the underground workings of the Broken Hill mines, and, as a consequence, an active fire prevention policy is a necessity...

Jan 1, 1929

By Muto S, Okada S

At Tamano Smelter, part of the furnace settler is electrically heated by electrodes placed internally. This practice provides good control of the settler conditions. The authors have been investigating improvements in furnace operations, especially to decrease the copper content in the slag discarded from the settler. The important operational points on the control of magnetite in liquid matte and slag are discussed on the basis of the thermodynamic calculation method developed by Prof. S. Goto. The behaviour of magnetite in the practical furnace has been studied by using a torsion magnetometer and a solid electrolyte oxygen-sensing cell.

Jan 1, 1980

The major greenhouse gas emissions from coal combustion are leading certain people to argue for uranium mining and nuclear power to meet these challenges. Although there is considerable rhetoric around promoting nuclear power as 'green' due to its relatively lower greenhouse intensity, a careful study of the data is required to properly underst and the sustainability of uranium mining and nuclear power and whether it can or should have a role in future energy supply scenarios. This paper presents detailed research and analysis on uranium mining, focusing on known economic resources, production, solid waste and water management, pollution issues as well as energy and greenhouse aspects. A particular focus will be on Australia and its operating and prospective uranium mines. Overall, the paper raises fundamental issues concerning the long-term sustainability of uranium mining and nuclear power and documents the greenhouse intensity of uranium production and the nuclear fuel chain.

Jun 1, 2010

By Forster I, Thilo A, Dean AK

A prototype production tool capable of operation in the hole sizes (

Jan 1, 1988

By LaBrooy S. R, Ritchie I. M

Problems with the cyanidation of copper-gold ores Copper-rich gold ores are becoming increasingly important both within Australia and overseas (Dayton, 1982; Deng and Muir, 1994; Muir et al, 1993; Sceresini and Staunton, 1991; Solis, Hefter and May, 1995; Wall, Hornby and Sethi, 1987). In Australasia alone over 30 copper-gold deposits have been reported (Muir et al, 1993). Table 1 lists several of the deposits that have been processed. TABLE 1 Examples of copper-gold deposits in Australasia. Name

Jan 1, 1997

The tankhouse of the electrolytic zinc plant at Nordenham is operating with a very high operating efficiency of 99 per cent. This has been achieved not only by strict control of the quality of the zinc sulphate cell feed solution but also by all the improvements in housekeeping in the tankhouse developed during the past years: aluminium cathode specification, cathode stripping cycle, edge strips, copper contacts, anode isolators, cell cleaning, fittings and washing devices. During 1987 to 1992 the casting department was completely remodelled in order to improve the quality of the zinc products, the safety of the operations and the flexibility. The remodelling includes the enlargement of the area for the casting shop, the storage buildings and the five casting lines on the same ground level. New lines for alloying products and for SHG25 kg zinc ingots have been constructed. The line for galvanising products has new equipment in some parts and the other lines have been modified.

Jan 1, 1993

By Watsford RMS, Wickham P

In October 1980 the two existing flotation circuits were combined into a single new circuit. This circuit used modern 11.3 m3 flotation cells which replaced 1.4 m3 units. Sometime after this change, a significant deterioration in metallurgical performance occurred. This paper describes the work done to discover the causes of deterioration in performance and actions taken. The program implemented to prevent a future occurrence is also presented. The work included analysis of routine plant data, analysis of surveys to obtain element and mineral flows on both a sized and unsized basis, some quantitative mineralogy, and analysis of some external factors.

Jan 1, 1978

By Wang S

Fragmentation is the basic concern in rock blasting and serves as the main measure of blasting effectiveness. A good estimation of fragment size distribution before blasting is very useful and helpful for selecting the proper equipment for loading, transporting, and crushing rocks. A fragmentation model is presented that is based on a hole by hole analysis and correlates the rock properties, burden, spacing, and explosive column with the blasted volume and fragmentation obtained. The drill bench is divided into three separate areas corresponding to different breakage mechanisms. They are: 1) a main breakage or casting area, 2) a secondary breaking area, and 3) an overbreak area. The boundary of the main breakage area is found from the magnitudes of strains in the stress waves and the tensile strength of the rock. The secondary breaking area is determined by stress wave reflections at discontinuities and interactions between colliding stress waves from adjacent boreholes. The overbreak area is that beyond the main breakage area "where the reflected tensile waves no longer break the rock. This analysis is applied on a hole by hole basis to locate the breaking points. Then connecting the breaking points on each side of a borehole forms the triangle of the main breakage area. This is repeated for the next hole and the remaining area is the secondary breakage area. After the angle and area for each hole are found the Kuz-Ram model is used to predict the fragmentation size distribution for each hole. Then summing up the size distribution for each hole gives the total fragmentation distribution. This analysis has been successfully applied to field tests performed in a limestone bench where the entire spoil pile was screened to determine the fragment size distribution. Knowing the explosive and rock properties the breaking area was found for each hole, the strain and stress values, the breaking point, and angle of breakage (104 degrees). The fragmentation size distribution was then calculated and compared to the field data with excellent agreement.

Jan 1, 1990

By Hendrix J. L, Nelson J. H

A study was conducted to examine how pretreatment of carbon-bearing gold ores with chlorine enhances gold recovery by cyanidation. It is hypothesized that metal species (including iron and copper) dissolved during chlorination adsorb on the carbon surface hindering the adsorption of dissolved gold. To test the hypothesis, samples of several sulfide minerals were subjected to reaction with sparged chlorine gas to determine which, if any, dissolve faster than gold under these conditions. Then, a synthetic carbonaceous refractory gold ore containing pyrite, chalcocite, activated carbon, and gold was subjected to gas sparging. The results of these experiments showed that chalcocite and arsenopyrite dissolve so that metal (copper and iron) is put into solution slightly faster than gold under the same chlorination conditions. Also, it was observed from the experiments that gold adsorbs on activated carbon during chlorination, but is replaced by copper and iron as the chlorination process dissolves more of the chalcocite and pyrite. The study concluded by investigating ferric chloride addition prior to chlorination to hinder gold adsorption on activated carbon.

Jan 1, 1991

By Lockhart D. A, Gleeson P, Lang S. C

The Glenrock Group forms the uppermost part of the Early Devonian to Early Carboniferous Burdekin Basin sequence in the Townsville hinterland, north Queensland. As redefined, three formations make up the Glenrock Group. The Percy Creek Volcanics (base), the dominantly epiclastic Mount Douglas Formation, and the Horse Pocket Volcanics (top). The Ellenvale beds unconformably overlie the Mount Douglas Formation and Percy Creek Volcanics and have been excluded from the Glenrock Group as defined by Wyatt and Jell (1980). Three facies associations are recognised in the Mount Douglas Formation: Alluvial Plain facies, Alluvial Fan facies and Lacustrine facies.Deposition of the Glenrock Group, began with the eruption of massive basalt and basaltic andesite lavas, probably in a volcanic arc setting. With time, the volcanism evolved to become more dacitic to rhyolitic in composition. Waning of the volcanic activity appeared to coincide with uplift of source areas (probably to the west). Deposition on an alluvial plain during this waning volcanic cycle, gave way to alluvial fans at the margins of the uplifted terrain. As the uplift ceased and the system became more mature, the alluvial fans gave way to widespread lakes. Rhyolitic ignimbrite and airfall tuff, interbedded with the alluvial plain, alluvial fan and lacustrine facies, indicate that some volcanism continued, probably vented in the uplifted terrain to the west.

Jan 1, 1990

The Permian rocks at Gympie were first studied as far back as 1868 in conjunction with the discovery of gold. The relationship of the Gympie Group to other sequences in the Gympie Composite Terrane is an important subject of investigations in a new mapping project of the Geological Survey Program of the Department of Resource Industries.In two areas the Gympie Group has been divided into four defined formations. They are the Highbury Volcanics (base), Ram mutt Formation, South Curra Limestone and Tamaree Formation (top) in the Gympie area, and the Mant basalt (base), Kolbar Formation, Gigoomgan Limestone and Teebar Formation (top) in the Gigoomgan area. Geochemical and lithological evidence from the basal volcanics of the Gympie Group (Highbury Volcanics, Mant basalt) indicate that they developed in an intraoceanic island arc setting. The overlying volcaniclastic sediments (Rammutt Formation, Kolbar Formation), which contain some continentally-derived material, are mainly of local derivation and shallow-water marine. A hiatus is present at the top of the Early Permian Rammutt Formation and Kolbar Formation. Following the hiatus, limestone sedimentation characteristic of a basin of restricted circulation developed in the Late Permian. There is some evidence of a hiatus between the limestone deposition of the Gigoomgan and South Curra Limestones and the overlying probable turbidite deposits of the Teebar and Tamaree Pnrmatinnc

Jan 1, 1990

By Daziel M, Corke P

Unit cycles in mining have not changed for many years. Productivity increases over the past three decades have mainly been achieved by using larger and heavier machines. This investment in size has probably reached the point of diminishing returns and increased productivity in the future will have to be generated by other means. One way of achieving this is through automation of selected unit operations, eg dragline overburden removal, truck haulage, ground support installation and secondary breakage. Although, in the past few years, there has been significant progress in this direction, we are still a long way away from even partial automation - especially in hard rock mines. This paper addresses the technical obstacles facing mining automation; suggests ways by which these obstacles may be overcome and identifies the role of industry groups and research providers in this process.

Jan 1, 1997

The BHP Billiton Cannington mine uses sequential flotation to treat a silver, lead and zinc ore supplied from an underground mine. The final products from the process plant are a silver rich lead concentrate and a zinc concentrate. Operational history of plant performance highlighted that the majority of valuable metal losses to final tailing occurred in the -5 ¦m fraction. Research completed on the flotation characteristics of this size fraction in plant feed resulted in the development of a split flotation process to improve the silver and lead mineral recoveries. Construction of a $A 9.5 million brownfield project to install the new split flotation circuit at Cannington was completed in July 2002. The circuit consists of three stages of cyclone classification to recover the ultra fine material to a final cyclone overflow stream, conditioning of this pulp to achieve optimal process conditions, and conventional rougher and three stage cleaner flotation to produce a silver rich lead concentrate. The rougher tail from the new circuit is recombined with the cyclone underflow streams and processed through the original lead-zinc flotation circuit. This paper discusses the circuit design, material properties, material selection for components of the circuit, operational practices and requirements to ensure the circuit succeeded in meeting production targets. The technology is subject of a number of patent applications including international application No PCT/AU02/00400.

Jan 1, 2003

Having provided basic data in the main paper I would now like to move on to discuss these areas in broader terms and to examine the various coalfields in terms of their tectonic setting and depositional environment and ultimately to make some brief comments on the factors which may have controlled deposition.

Jan 1, 1975

By J R. Manuel, M J. Peterson

Selected drill core samples from a Ferrobamba-limestone-hosted, magnetite-haematite skarn deposit, located in the Apurimac department of the Andahuaylas-Yauri skarn/porphyry belt of south-eastern Peru, were mineralogically and texturally characterised to gain a preliminary indication of the deposit's potential as an iron ore resource. Optical microscopy, X-ray diffraction (XRD) and scanning electron microscopy/electron probe microanalysis (SEM/EPMA) techniques were utilised to determine the characteristics of magnetite, haematite and/or goethite dominated ore types, including variations in the relative proportions and textural relationships of the ore and gangue minerals. The deportment of elements deleterious to processing performance (eg copper, sulfur and potassium) was determined and the beneficiation potential of the samples was briefly assessed. In drill core sections, the ores are grey to reddish in colour, massive and 'metallic' to dark brown and earthy in character, moderately hard and porous (macro and microporous), with variable gangue infill. Ores often appear weathered, typified by ochreous goethite staining and common minor goethite (except in dense core fragments), occasionally exhibiting a more friable texture with coarse magnetite/martite grains. Silicates and lesser carbonate gangue are visible as blue-green to beige to white scaly and/or shaly surface coatings, and finely particulate infill, often goethite stained. Sulfide-rich ore types also occur in part of the deposit, but are restricted to specific drill holes. Magnetite grain size is relatively coarse, compared with magnetite from typical banded iron formations, whereas discrete silicate gangue is mainly bladed/fibrous and/or layered and micaceous in form. XRD analysis indicates the presence of vermiculite, serpentine, stilpnomelane, chlorite, actinolite and clays. There is a spectrum of ore types representing the gradation from 'fresh' (magnetite-dominated) to oxidised and weathered (martite/goethite-dominated). Martite-dominated samples are generally higher in grade, due to leaching and removal of silicate gangue, resulting in higher macroporosity. Where gangue has been leached out, partial replacement by vitreous goethite and/or hydrohaematite is typical, often preserving the fibrous/layered characteristics of the original silicates.

Jan 1, 2009

Economic conditions dictated the lead time from concept to commissioning of the Kambalda C.I.P. Plant. The high gold price prevailing at the time the Victory ore-body was discovered provided the impetus to establish a treatment plant with the utmost haste. Consequently only limited metallurgical testing was possible. Fortunately the Kambalda Metallurgical Department had experienced gold metallurgists among its' staff. This enabled a rapid assessment to be made of the ore types to be treated. Flexibility was the keynote in the plant design. Overseas practice and experience was drawn upon extensively, but it was known that problems uniquE to the Kambalda Plant would be encountered due to the high nickel content of the C.I.P. Plant feed and the difficult clays in some of the areas. These fears were well founded and problems have been experienced. However the plant design has enabled these problems to be absorbed, if not overcome, and design production rates were achieved and maintained within three month; of start-up.

Jan 1, 1982

By Black LP, Law SR, Oversby BS, Mackenzie DE, Wyborn D

Three volcanic sequences of different ages occur close together in the Burdekin Falls area, southeast of Charters Towers in northeastern Queensland. The oldest is equated with the Cambro-Ordovician Mt Windsor Volcanics, and consists mostly of strongly deformed, regionally metamorphosed rhyolitic lava and minor feldspathic to quartzose sandstone. This unit is overlain by folded but unmetamorphosed Upper Devonian-Lower Carboniferous volcanics (DCv) of the lowermost Drummond Basin sequence. The primary volcanic facies of (DCv) principally comprises andesitic and rhyolitic lavas, and dacitic ignimbrites. Similar volcanics are widespread in the lowest formations of the Drummond Basin sequence elsewhere, and dominate that sequence east of the Anakie Inlier. The youngest volcanic sequence is Late Carboniferous and composed of lower, more deformed, compositionally diverse ignimbrites, lavas and conglomerates, overlain by generally less deformed rhyolitic ignimbrite sheets. The upper part is equated with the Bulgonunna Volcanics which extend 90km south to the Mt Coolon area. The Burdekin Falls area contains an ignimbrite stratigraphy different from that in the south. However, one of the most voluminous ignimbrites (Locharwood Rhyolite) in the southern stratigraphy is also present in the north, enabling the two to be correlated.Each of the three volcanic sequences reflects proximity to eruptive sources. Both the volcanics at the base of the Drummond Basin sequence and the Late Carboniferous volcanics are largely the products of subaerial eruptions. The former were erupted from several intermediate-composition volcanoes, and the latter from multiple-vent silicic calderas. All three sequences are considered to be prospective for precious and/or base metal mineralisation. Polymetallic massive sulphide deposits occur in the Mt Windsor Volcanics farther west, and many epithermal gold prospects and mines are hosted by the volcanics at the base of the Drummond Basin, especially east of the Anakie Inlier. The Late Carboniferous volcanic sequence is deeply eroded, and co-magmatic high-level plutons are widely exposed; this sequence may therefore be more prospective for deeper-than-epithermal mineral deposits.

Jan 1, 1990

By Wilson J. R

The main mining method employed at Mt Lyell is sub-level open stoping with a typical extraction level interval of 100 m and sub-level intervals of 30 m. Currently, pillar blasts provide the major portion of broken ore and firings are in the order of 200 000 to 300 000 tonnes while future firings of 500 000 to 300 000 tonnes are planned. Improvement of blasting techniques in these mass firings has been necessary for the following reasons. 1. Extremely wet ground conditions have adversely affected ANFO performance and placed extreme pressure on the charging and priming phases. 2. As pillar blasts increase in size the problems of wet ground conditions are accentuated resulting in very slow loading of wet upholes with cartridged gelignite and unreliable charging of the remainder with ANFO. 3 Fragmentation in pillar blasts has suffered because of the above, result- ing in increased secondary breaking costs and difficulty of extraction.

Jan 1, 1977

By Hatherly P, Holt GE, McNally G

The current methodology for delineating and subsequently evaluating coal reserves is based on the use of vertical drill holes and surface based geophysics/geology. These techniques have three major problems, these being respectively:-a) Vertical drill holes can only provide a small sample of the coal seam and stratigraphy. Therefore the planar variation in coal reserve and environment parameters can only be approximated.b) Although surface based geophysics has had its fair share of success in recent years, there are still environments which have masked the finding of major structures.c) Access to drill sites is difficult at some locations due to mountaineous terrain, standing water and environmental impact.

Jan 1, 1985