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By J H. J Holtzhausen

Never has there been more focus on the health, safety, and well-being of our employees at the workplace. Ever evolving expectations of individuals, companies and clients are shaping regulatory reviews and advancing standards across the world in the drive to zero harm. The technology is advancing at a rapid pace, which is now allowing continuous real-time monitoring of contaminants to take place in the harshest of environments.

Oct 12, 2022

The need to schedule ore production to make maximum use of the strength gained by cem- ented fill during curing is discussed, to show how cement content and hence fill cost can be kept down for any particular operation. Results from laboratory testwork on Isa Mine fill conducted by the author while employed by Mount Isa Mines Limited form the basis of the Discussion

Jan 1, 1973

By Clements R. J, Davey J. M

Development of the process from the pilot stage to the current operation of the Capel, W.A. plant is briefly described. The design criteria for a larger sized plant are discussed together with factors that relate suitable feedstocks and coal types to the capital cost, capacity and product grade of future plants at locations other than Capel. The application of the process to the direct reduction of iron ores is briefly discussed including its commercial application at Rockwood, Tennessee.

Jan 1, 1979

By DiStefano AB, Dale SG

This paper describes the laboratory study implemented to investigate the application of the subaerial technique to tailings disposal for the proposed Olympic Dam Mine. The results of the study and the resulting design parameters are presented. The subaerial technique of tailings disposal is described and the advantages of the method for disposal in arid climates highlighted.

Jan 1, 1984

By Maloszewski J, Kidybinski A, Sawka B

A forecast of mining conditions in Upper Silesia collieries for the beginning of the 21st century has special focus on average depth of mining, energy of seismic tremors induced by mining and energy of dynamic loads on roadway supports. A method of dynamic loads calculation is based on volume of failed rock surrounding an opening and the seismic energy of tremors anticipated. New types of yielding steel arch supports have been designed to resist massive static and dynamic loads and a system of supports has been tested both on 1 : 10 scale models and in natural size. The support sections used are 29, 36 and 44 kg/m.

Jan 1, 1988

By Myers PA, Noble MR, Lawrence JS, Cannings WR

The Perseverance orebody presents the Agnew Mine with a wide variety of geological settings, necessitating the application of several mining methods within the limited strike length being extracted.Mining methods have been introduced and modified during the six years' production history of the property and that evolutionary process remains very active.The methods used, in use or planned, are:Hand held scraper cut and fill Hand held mechanical cut and fill Post pillar cut and fillOpen Stoping (uphole benching) Modified vertical crater retreat Sub-level caving

Jan 1, 1985

By Reeves T. J, Hansen J. Y

Dense medium cyclone theory, supported by extensive experimental and plant-scale evidence, demonstrates that medium rheology (stability and viscosity) substantially affects cyclone performance in mineral applications.Two instruments have therefore been developed to allow medium stability and viscosity to be-monitored in the plant environment. The instruments are described, and examples are given of their application in full-scale plants.

Jan 1, 1989

Joint ventures exist as a means of sharing risks and obeying regulations. An unincorporated joint venture allows a company to take a share only of a project yet allows that company to treat such share as though it were an integral part of the company. The nature of the risks inherent in many ventures is described and comparisons made with alternative corporate vehicles. Different procedures for managing joint ventures are also reviewed and the types of problem encountered in establishing and operating joint ventures are discussed. The basic characteristics of successful joint ventures, in Australia, are listed and a conclusion reached that, despite its difficulties, the joint venture will continue to proliferate as a corporate vehicle for project development.

Jan 1, 1983

By Callinan AN

Broken Hill Proprietary Company Limited have recently commissioned a 14 Megawatt power station adjacent to its underground coal mining operation at Appin NSW. The power station is fuelled by methane gas extracted from the coal seams 500 metres below the surface. The methane is compressed and cooled prior to its injection into the combustor of a single shaft gas turbine. The turbine is coupled through a reduction gearbox to an alternator. There is sufficient power generated to cover colliery load, with any excess being exported to Prospect County Council, which is the supply authority for the south western region of Sydney.

Jan 1, 1987

The economic significance of a fundamental understanding of the mineral pyrrhotite is dis- cussed. Particular emphasis is placed on the relationship of other sulphide minerals to the pyrrhotite when it is the major sulphide mineral present in an ore body. Studies of the Kambalda nickel deposit are used to give a better under- standing of (a) the genesis and other character- istics of a particular ore body (b) the textural relationships between pyrrhotite and other sul- phide minerals (c) magnetic properties of natural pyrrhotite, and (e) the oxidation and supergene processes that take place in a sulphide ore body.

Jan 1, 1972

By Haskard R. W

A method of raising has been developed at Cobar Mines Pty Ltd's CSA Mine which has achieved advance of up to 6 m in a single blast and raises are now developed which have averaged 4.2 m per blast. The method is a form of Long Hole Raising and is applicable to short raises of less than 50 m length. Blast holes are column charged and initiated sequentially with short delay detonators (millisecond). The equipment used to drill the raising blast holes consists of normal production drilling rigs and accessories and no other special equipment is required. The method has significant advantages in rates of performance and fits neatly into production drilling and blasting schedules. The method is also far safer than any non-mechanical or conventional means of Raising.

Jan 1, 1983

Perhaps the only thing certain about an address that purports to look into the future of any human endeavour is that time will prove it :.o be inaccurate. In undertaking the dubious, but oft-times necessary business of prediction, thr, historian will base his/her forecasts on tr-ands of the past, the speculator on current events, and the politician on what he/she would dearly like to see happen. The thoughts expressed in this address seem to have arisen through exercising a combination of all three of those philosophies but, hopefully, with a smat- tering of pragmatism.

Jan 1, 1988

The screening of iron ores, sinter and coke, and investigations undertaken to improve screening efficiency and cloth life are discussed. The major modifications to coke screening proposed with the construction of No. 7 coke ovens battery are briefly described. The major problem areas were identified as screen cloth blinding and pegging, feed presentation and screen overloading. Blinding and pegging have had a significant effect upon screening efficiency with the screening of sinter, coke breeze and wet iron ores in particular. Pegging can be reduced or eliminated by the correct selection of aperture size and shape, screen excitation and slope, and screening medium. Blinding encountered with wet coke breeze was a particular problem in which no significant progress was made.

Jan 1, 1984

By Treglown N

In any mining operation the curtailment of rising operating costs is of prime concern to management.One area of activity where costs are often disguised is that of longhole secondary breakage.This paper outlines sane operational techniques that have been considered and tested, resulting in improved fragmentation fran longhole stope blasts at New Broken Hill Consolidated Limited mine, Broken Hill, NSW.

Jan 1, 1985

HISTORIC SIGNIFICANCE OF EXPLOSIVES TO MINERAL PRODUCTION The ancient method of breaking rock was to build a wood fire against the face, heat the rock through and then pour water on the heated ore-bearing rock to cause it to break by tension. It was too slow and costly as the forests around the mines were cleared and transport of wood became difficult. Black powder had been used for 300 years as a gun propel- lant. ('Black' after Berthold Schwartz, a German monk, Figure 1, and the inventor of the gun who was given the epitaph `Here lies Berthold the Black, the most abominable of inhumans who by his invention has brought misery to the rest of humanity'). Only at the beginning of the 17th Century, black powder was introduced for loosening rock in European mines. In 1802 Dupont started black powder manufacture on the Brandywine Creek. The ignition train of powder was enclosed in goose quills, straws, rushes, paper or wooden tubes. The time interval between igni- tion and blast was pure speculation.

Jan 1, 1988

Gold at Renco occurs in association with pyrite, pyrrhotite, chalcopyrite and quartz and is confined to a series of brittle fractures and fault breccias (reefs) preferentially developed within an anastomosing ductile shear zone. During late Archaean crustal movements both the orebody and the enclosing host rocks were deformed within a series of east-north-east striking, southerly dipping, shear zones. The reefs within these shear zones are now texturally different to those away from the shear zones, and this difference is reflected by differences in the way the gold is distributed in the two reef types. These differences are not taken irto account by the software package currently being used to generate kriged plans of gold grade and reef thickness and this may explain some of the inaccuracies found in these plans.

Jan 1, 1990

By Merry N, Cocks T

The mineral exploration industry is increasingly aware of the importance of the relationship between mineralogical data and geochemical assay results. However, until recently, the cost and time constraints of most techniques for analysing alteration mineralogy have precluded detailed alteration studies. These impediments have been reduced by the development of the Portable Infrared Mineral Analyser (PIMA), a field portable infrared spectrometer that allows rapid (in field) and cost effective analysis of alteration minerals including subtle variations in mineral crystallinity and Composition.

Jan 1, 1995

By Dinuzzo P, Wychie J, Desoe C

The Selwyn Gold-Copper Mine is located 150 km southeast of Mount Isa within Proterozoic units of the Mount Isa inlier (Figure 1). Mineralization in the mine area is associated with strongly sheared ironstones and iron rich schists at the base of the mid- Proterozoic Staveley Formation. The ironstone horizons outcrop as a series of dominant ridges over a 10 km strike. Economic gold-copper mineralization has been defined in 4 separate zones within a 3.5 km length of the outcropping ridges. A current combined geological resource for the deposits is 5.3 million tonnes of 5.0 g/t Au and 2.02 Cu. Weathering of the deposits has resulted in a pronounced vertical zonation of mineralogy, especially copper, within the ore zones. This has produced 3 separate ore types which require different treatment techniques. The categorization is based on copper content and zones are termed leached (surface), oxide and sulfide. Ore removed from the pits will be mainly leached and oxidized with minor sulfide near the pits final depths, while the underground ore will be from the sulfide zone with minor oxide in some areas.

Jan 1, 1989

This problem is seen as being central to a number of peripheral problems. Of these, the following are considered to be of major importance: 1. Reserves. Changes in Quality. Depths at which they occur. The effects of catchment and water storage areas. The effects of urban development. 2. Environment and the compat- ibility of mining and preparation of coal. 3. Transportation of Coal. J. tabour.

Jan 1, 1976

By Pitkajarvi J

Waste rock dilution causes mill feed grade to be lower than mineral resource grade. In nickel mines relative grade decrease (dilution) may be tens of per cent because of irregular ore boundaries and weak wall rocks. Five per cent dilution costs millions of dollars annually in medium size underground mine. In Outokumpu Group selective bench and fill stoping, cable bolting/shotcrete-skin support and fast ore boundary definition (OMS-logg in-hole logging or sludge sampling) are the key tools in dilution control. Commitment of the whole organisation to keep dilution low is also needed. Dilution sources and effects are discussed with examples of the dilution control methods applied in Outokumpu mines.

Jan 1, 1996