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By Hedley TP

Success for underground coal mine operators in the 1990's and beyond will be dependent upon better understanding of the dynamics of their operating environment, and extension of emerging technologies to reach new levels of output and productivity. The Collieries Division of B.H.P. Steel International Group clearly identifies with the concept of business/product life cycles - and the need to adopt strategies that can drive the business successfully into the future. Three main thrusts within BHP Collieries Division relate to: 1) Detailed assessment of current mines to determine: a) The real output potential of the current facilities. b) What factors now inhibit the full potential from being realised. c) Opportunities that exist to enhance overall mine performance. 2) Based upon the findings of these studies, putting into place cost effective strategies and systems for the ongoing "tuning" of the mine. 3) of new/improved technology primarily in areas of: a) Coal cutting and underground coal clearance. b) Controlling the overall mine gas Regime.

Jan 1, 1987

By A Baker

Hail Creek Mine is an open cut coal operation owned by Rio Tinto. It is located 120 km south west of Mackay in the Bowen Basin region of central Queensland. Opened in late 2003, the mine produces two high quality coking coal products that are used in the production of steel in various overseas markets. Hail Creek is a dragline and truck/shovel operation with a capacity to mine eight million tonnes per annum. In 2010, the production was more than seven million tonnes.Traditionally, coal seam edge loss had been minimised on site by the practice of coal edge buffering. Importing buffer material can be quite expensive as it requires a large involvement from the truck and shovel or dozer fleet. In order to minimise this expense, a program of front splitting was introduced on site. Front splitting however involves an additional blast interaction which places added pressure on mining schedules. Both these methods of coal protection demonstrated a significant benefit with coal loss being reduced by approximately seven per cent (absolute) compared to traditional cast blasting.With the application of electronic detonators at Hail Creek the new blasting practice of dynamic buffering is able to be performed on site. Dynamic buffering refers to a blasting practice where two or three separate blasts are initiated during the same blasting event (front-split, cast and at times presplit). The process involves firing a front-split and allowing it to have time to settle and buffer the coal edge prior to the cast blast initiating. This practice is only made possible with the use of electronic detonators and the effective absence of a surface burning front. Current practice at site involves the front-split being fired (occasionally at the same time as the presplit) and the main cast blast being initiated several seconds later. Dynamic buffering is now used for all cast blasts to coal at Hail Creek. Electronic detonators have allowed Hail Creek to achieve reduced coal losses by buffering the coal edge without compromising the mining schedule.

Nov 8, 2011

The patterns of occupational health pro- grammes in mining and metallurgy are discussed in relation to the impact of chemical and phy- sical hazards on the health of workers in these fields. Mining and metallurgy are quite unique in that their history and practice embrace virtually the total spectrum of occupational health problems and hazards as understood today. A panoramic concept of the possibilities would comprise the following fields: 1. The Pneumoconioses or Dust Diseases. 2. Physical stress due to exertion, and exposure to heat and humidity in deep mines. 3. The toxic effects of various metals in the mining of ore. The most obvious are lead, mercury, arsenic and manganese. 4. Diseases associated with mining. These include leptospirosis, ankylostomiasis and mycotic infections of the skin. 5. The Beat Diseases of coal miners working in narrow seams. 6. Illumination problems and miners nystagmus. 7. Geographical and climatic problems

Jan 1, 1975

By Lewis IE

Copper-lead dross is a by-product of the refining of lead bullion produced by the Imper- ial Smelting Process. This dross contains some 27 percent copper, 50 percent lead, four percent zinc and one percent sulphur. An ammonium carb- onate leach at atmospheric temperature and pressure removed the copper from the dross while the lead zinc and precious metals remained in the leach residue for return to the smelter. The leach solution containing the copper was then purified by liquid-liquid ion exchange using LIX64N in a kerosene diluent. ("LIX" is the registered trade mark of a range of hydroxy oximes marketed by General Mills Inc.) The pilot plant had a capacity of 0.7 kg/h of CuSO4,5H20 and was operated for some fifty days on a two shift basis. Copper sulphate of excellent purity was produced, and the results obtained indicated that a copper recovery of ninety percent from the dross could be expected from a commercial installation.

Jan 1, 1975

Hong Kong continues to display a remarkable enthusiasm for undertaking ambitious tunnelling schemes despite apparent recessions in the Asian economy. This paper provides an outline of tunnel projects currently under construction, those recently tendered and a glimpse of the extent of forthcoming projects which, according to Government sources, carry a price tag of HK$ 200B. Committed works will cost about HK$ 15B and involve a variety of TBM and drill and blast tunnels. These include the recently tendered works for KCRCÆs West Rail and MTRCÆs Tseung Kwan O railway extension, together with five no retendered TBM drives for the Strategic Sewage Disposal Scheme (SSDS) following forfeiture of the works by the Campenon Bernard-Maeda JV in mid-1997. The JV claimed unreasonable specifications leading to unacceptable levels of water inflow and dangerous working conditions. Key technical issues that are now arising in Hong Kong are:the general use of design and build contracts for bored tunnel contracts;a trend to accept TBM options for relatively short drives in urban areas;the use of æfixed-priceÆ contracts which in the current competitive market, can encourage tenderers to take contractors to take very high risks; andthe difficulty of predicting and managing water inflows in rock tunnels.This paper also includes a new empirical method of predicting water inflows in rock tunnels, and makes recommendations for managing these on-site.

Jan 1, 1999

Most people are familiar with Euclidean dimensions: zero for a point; one for a line; two for a plane; and three for a volume. Howeverbobjects are not actually Euclidean, but lie somewhere between Euclidean æend-membersÆ with a non-integer fractal (or æfractionalÆ) dimension. The fractal dimension D is a measure of the relative importance of large versus small. Consider the trace of a coastline on a map. It has a fractal dimension (1 =D =2) somewhere between a line (dimension = 1) and a plane (dimension = 2). The more tortuous the coastline, the higher the fractal dimension, and the closer it becomes towards a plane. The concepts of fractals and spatial geometry can be applied to a wide range of geologicaVmining problems as well as than those dealing with space. One commonly quoted fractal relation is the log-log relationship of ore-grade and tonnage. Until recently, we have never been able to define or measure spatial-geometry, but new developments in mathematics have provided a means by which to quantity and apply it to our problems.

Jan 1, 1992

By Short KC

The Hunter Region, with a major part of the coal resources of New South Wales and a long history of coal mining, has experienced a rapid expansion of coal resource development in recent years. While there are inevitable conflicts between mining, urban development and related infrastructure, and between mining and other resources, the application of sound planning practices, and improved co-operation and co-ordination among the various parties, helps to reduce such conflicts. The planning process involves consideration of factors such as transport- ation (including port facilities), mine subsidence, provision for surface facilities, a,iC the need for buffer 'ones. In addition, provision must be made for urban expansion, often co-existing or in close proximity to present or future coal mining development. Approval of coal mining developments takes place within the legislative framework of the Environmental Planning and Assessment Act, 1979 (EPA Act), the Coal Mining Act, 1973 (CM Act) and the Mining Act, 1973. Considerable effort has gone into stream- lining and co-ordinating the procedures under these Acts. The EPA Act provides for regional and local environmental plans, as well as a linked process of development control and environmental impact assessment. The CM Act provides for the grant of exploration and coal mining titles and mechanisms for the responsible management of Mining.

Jan 1, 1987

By Kelly GD

Prior to 1986, users of satellite based remotely sensed data were almost exclusively reliant on the United States Landsat series of satellites to monitor our Earth's resources. This situation changed when France, Belgium and Sweden launched SPOT-1 in 1986. The year of 1988 saw the Japanese also enter into the earth resource satellite business. The Japanese launched an earth resource monitoring satellite with an emphasis on marine resources, hence the name MOS-1 (Marine Observation Satellite). Many more remote sensing instruments are planned for launch by these nations and others in the next 10 years.

Jan 1, 1990

One major aim of the operation of Aberfoyle's matte fuming pilot plant was to assess refractories performance in the process working vessel, a SIROSMELT furnace. High wear rates were expected and whether these could be tolerated was an important question. During operations a range of refractory types was evaluated in both insulated and water cooled furnace designs. Furnace operations enabled lining wear measurements to be made. Results confirm that existing technology can solve any expected refractory problems. Design aspects that should be included in commercial furnaces are shown.

Jan 1, 1984

The Newmont Waihi Operations mill has undergone significant growth over its life. Initially designed as a single SAG mill operation, the circuit has been progressively upgraded since 1988 from a nameplate capacity of 600 000 tonnes per annum to the current rate of 1.3 million tonnes per annum. With future mining potential there is renewed interest to increase the processing rate even further. Over the next twelve months five sustaining capital projects will be undertaken and two major eco-efficiency projects will be completed. With the exception of the large grinding mills, most equipment on a gold treatment plant is replaced after 10-15 years. Waihi Gold mine has been operating for 14 years and has just recently received approval to replace equipment in five main areas; carbon elution, carbon regeneration, scats crushing, intertank screens and variable speed drives. Each project has been justified on improved process efficiencies and operating/maintenance cost savings. The two eco-efficiency projects involve a water balance model and a cyanide optimisation project, both of which are Corporate key performance indicators (KPI).

Jan 1, 2002

The Paracale gold region had been known for hundreds of years, but the first professional attempts to work the lode and alluvial deposits were made only in the 1890s by the London-based Philippines Mineral Syndicate. Complex ores, transportation problems, and the Philippine Insurrection halted operations. Ultimate success went to American firms, though Frank Karuth's Philippines Mineral Syndicate had pioneered the field.

Jan 1, 1987

By M Zhu, G Tranell, N Simkhada, K Jakovljevic, M Wallin

Silicon is a vital element in many products today, such as electronic components, solar devices, high-quality alloys, and many others. The growing global demand highlights the need for the development of sustainable production methods to meet this demand as an alternative to the current carbothermic reduction, submerged arc furnace (SAF) based process. An alternative to this is the aluminothermic reduction of quartz in a CaO-SiO2 slag, which not only reduces direct carbon dioxide emissions but also promotes the utilisation of secondary raw materials such as quartz fines, aluminium dross and scrap as well as secondary alumina (SA) from dross recycling. In the current study, the effects of SA and CaF2 additions to slag on the resulting metal composition and metal yield were explored. Results were compared with thermodynamic simulations using FactSage™ 8.1. Experimental results show that, in agreement with thermodynamic simulations, the silicon content of the alloy is increased, while the Ca is decreased for starting slags where CaO-SiO2 is partly replaced by CaF2. Similarly, the addition of SA to the initial slag results in an alloy with a higher silicon content.

Jun 19, 2024

By Wyborn L, Giddings J. W, Plumb K. A

The McArthur, Balma (new name) and Habgood Groups are thick (up to 4.5 km) correlative sequences of shallow water evaporitic carbonates, mudstones and sandstones that are exposed largely within the Batten, and southern and northern Walker Fault Zones (Batten and Walker Troughs) of the McArthur Basin respectively. Recent re-mapping of the Walker Fault Zone has provided data for refined stratigraphic correlations between these groups. Two significant hiatuses are now recognised within the Balma Group (base of Vaughton Siltstone and base of Yarrawirrie Formation) and these may represent tectonically-generated sequence boundaries which may correlate with similar local hiatuses within the McArthur Group such as at the base of the Teena Dolomite and Lynott Formation respectively.

Jan 1, 1994

By Gottlieb P, Sutherland D, Jackson R

The QEM'SEM system for automated image analysis of mineral samples is described. Details of the equipment are given together with information on the methods of measurement. Finally some practical applications are described where QEM*SEM has been used for the solution of metallurgical Problems.

Jan 1, 1989

By D Craw

The Rise and Shine Shear Zone is a mineralised low angle deformation zone traceable for at least 7 km through biotite zone schist of the Dunstan Range, central Otago. Rocks from the shear zone obtained from recent drillholes are unweathered and facilitate paragenetic studies. There is a progression of mineral deposition from semiductile foliation-parallel shearing, to subsequent folding, and brittle fracturing. Sheared rocks are dominated by microshears containing fine grained hydrothermal muscovite and rutile that has recrystallised from metamorphic muscovite and titanite respectively. Euhedral pyrite occurs within segregations in the schist and is locally brecciated by the shears.   Arsenopyrite occurs within microshears and is intergrown with hyrothermal muscovite. Fractures within relatively undeformed schist are filled with ankerite, siderite, chalcopyrite, sphalerite and galena and these veinlets also crosscut the microshears. Locally the schist is folded and zones of brecciation, silicification and vein deposition overprint the rock. Vein quartz and albite predominate and arsenopyrite and gold infill breccia matrix and crosscutting veinlets. Sulphide deposition began in the later stages of metamorphism with pyrite deposited in quartz-albite segregations. Subsequent shearing caused brecciation of some grains and accompanied deposition of arsenopyrite ¦ gold and rare sulphides along foliation-parallel microshears. Minor amounts of chalcopyrite, sphalerite and galena were then remobilised in ankerite veins that crosscut the shears. In areas of high strain, arsenopyrite was then deposited as euhedral grains in veins and breccias. Synmineralisation deformation caused the brecciation of some grains and gold was deposited infilling fractures in the arsenopyrite. The paragenetic sequence shows gold mineralisation occurred in two distinct sets of structures (semiductile and brittle) that formed at different times in the formation of the shear zone.

Jan 1, 2006

The treatment meIhods selected for the concentrator at Cobar Mines Pty. Ltd. called for a high degree of automatic control of both the grinding and flotation sections.The resulting concentrator layout includes a central control room overlooking both grinding and flotation sections. The control room houses process recorders, controllers, and indicators. together with motor stopstart stations and alarms.Plant instrumentation includes load cells and variable speed hydraulic drive feeders for feed-rate control of autogenous mills, together with nuclear density gauges, differential flow transmitters, and pneumatic control valves for water and pulp density control.Flotation cell pulp levels are controlled by floats and pneumatic actuators; flotation reagent controls include magnetic flowmeters and time-operated solenoid valves.

Jan 1, 1969

By C Li, D O’Dea, R Moreno-Atanasio, T Honeyands

The behaviour of iron ore granules in the feeding process of sintering is significantly influenced by the material properties of the granulated mix. Therefore, the measurement of key material properties of the iron ore granulated mix is indispensable prior to the simulation of the sintering process based on the discrete element method (DEM). In this paper, three key property parameters of the iron ore granulated mix, apparent density, elastic modulus and rolling friction coefficient, were measured in laboratory-scale experiments. For different sintering processes, the moisture content of the granulated mix normally varies according to the specific requirements for granule size distribution and operating conditions. Therefore, understanding the effect of moisture content on the property parameters of iron ore granules is very helpful in accurately determining the property parameters for DEM simulation work. In this paper, six groups of iron ore granule samples with six levels of moisture contents were prepared through granulation and the trends in apparent density, elastic modulus and rolling friction coefficient with the increase of moisture content were plotted and analysed based on the measurement results. The results show that as moisture increases from 6.9 per cent to 9.1 per cent, the apparent density decreases from about 3000 to 2800 kg/m3. With moisture increasing within the same range, the elastic modulus first decreases from over 200 MPa to below 100 MPa and then reaches a relative constant value of about 40 MPa at higher moisture contents. Rolling friction coefficients are measured using two methods with both indicating a similar trend, with the rolling friction coefficient first decreasing and then rising as moisture increases from 6.9 per cent to 9.1 per cent. The relationship between µr and µ’r is assumed to be similar to that between static and dynamic friction coefficients.CITATION:Li, C, Moreno-Atanasio, R, O’Dea, D and Honeyands, T, 2017. Variation in property parameters of iron ore granulated mix with moisture content, in Proceedings Iron Ore 2017, pp 79–84 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

The areas of concern lay in the processing of, and the subsequent hearing into, Waihi Gold's resource consent applications to extend Martha Mine. The proposed amendments to the Resource Management Act 1991 might see the introduction of contestability in the processing of applications - which would have assisted Waihi Gold; and the use of commissioners to hear the applications, with a right of appeal to the Environment Court on points of law only. It is also proposed to have major applications heard directly by the Environment Court. If Waihi Gold's applications had been heard at first instance by the Court, the delays in time and associated costs would have been reduced. However a hearing by commissioners only would not have been satisfactory, there being no right of appeal against the conditions of consent, which if implemented as granted by the Councils would have had a significant impact on the costs associated with the extended project.

Jan 1, 1998

A saturated, metal-free solution of alum can be used as a fiocculant to speed up the sampling procedure during a geochemical survey of stream silts.

Jan 1, 1969

By Hughson B

The need to prevent the sterilisation of coal stems directly from the fact that it is a non-renewable resource. In N.S.W. a vast amount of coal resource is located under major public utilities such as freeways, railways, stored waters, pipelines carrying gas, water and sewage, and transmission lines. Total extraction has occurred under freeways, transmission lines and pipelines with little or no damage. Where damage has resulted, the cost of restoration was only a small fraction of the value of the coal recovered. However, coal at present is being sterilised and perhaps lost for ever under stored waters and railways. If engineering solutions are available for mining under these improvements economically and with maximum safety, then coal should be extracted and utilised to the benefit of the State.

Jan 1, 1986