Search Documents

Comprehensive occupational health and safety legislation in Australia is comparatively recent. It follows the examples set in U.S.A. and U.K. a decade or more ago. In Western Australia the Occupational Health, Safety and Welfare Act was proclaimed in April 1985. It still has a long way to go before it achieves all its objectives. The mining industry has developed a substantial body of health and safety regulations under the Mines Regulation Act. Considerable practical expertise in such matters already exists, much of it developed from hard won experience. As a result it would prefer not to become engulfed in the new legislation. It would prefer to build upon the cooperatively developed policies and workable practices in the field of occupational health and safety with which it is familiar. Associated Minerals Consolidated Ltd. is a leading mineral sands producer in Western Australia and has continuously developed its occupational health and safety policy and practices. Under the banner of "Resource Control", AMC seeks to provide a safe and healthy working environment at all times. This is being achieved through a strategy of a policy, a defined organisational structure and a detailed programme, which together comprise the "Resource Control System". Some of the activities and achievements of AMC in the field of occupational health and safety are compared with the objectives of contemporary legislation, and details of some of the specialised areas of the Resource Control Programme are discussed. The paper will also highlight and discuss impractical areas of potential legislation.

Jan 1, 1986

Urban railway systems need high invest- ments, especially if their routes and stations have to be placed in the subsurface. In the FRG the construction and equipment cost of urban underground railway systems are in the range of 60 to 100 Mill DM per km tunnel. For this reason, track sections on the surface and on elevated structures are used as far as that is possible. Considering whole systems, the costs are in a range from to 45 Mill DM per km length for a metro system with about 80 % of its tracks and stations in tunnels and from 20 to 25 Mill DM per km for a light railway system with about 25 % subsurface infra= structure. The amount of route lengths in tunnels depends on the size of a city, the situation regarding above ground structure and free space on the surface, the level of service quality which has to be achieved with the railway system etc. Despite of the urgent needs to improve the transport conditions there very often arise doubts if an urban railway system is really necessary and can be justified in an economic sense. The experience from many cities around the world shows, that there arise a lot of benefits from urban railway systems, especially with larger sections placed under- ground. They are to be found in the interests of the operator (f.e. operating costs), the user (travel time, quality of service etc.) and regarding social aspects (environmental protection, accidents, consumption of energy Etc.).

Jan 1, 1987

By Kuzugundenli OE, Nagaraj DR

Organic complexing agents have received special attention over the past few decades in the search for reagents for improved flotation separation of minerals, especially non-sulphides. The majority of such reagents that have been proposed over the past few decades have remained largely a laboratory curiosity, except perhaps alkyl hydroxamates, because their selection is seldom based on commercial viability. In this regard, the choice of complexing agents such as oximes may be more realistic because of their widespread use in solvent extraction of copper. Our earlier studies have confirmed that they are also effective as collectors for copper oxide minerals, including chrysocolla which is the most difficult copper mineral to beneficiate. The flotation behaviour of chrysocolla for several structurally-related hydroxyoximes were studied as a function of pH and oxime concentration and the role of structural features examined. The structural changes studied included substitutions in both chelating and non-chelating parts of the molecule. The results indicated that, contrary to expectations, many of the structural changes in the basic molecule, salicylaldoxime, do not have a positive effect on collector efficiency. The reduction in collector efficiency is rationalised on the basis of possible steric factors affecting complexation and packing of the collector species on the mineral surface as well as effects due to changes in electron density brought about by substituents. Introduction of alkyl substituents on the oximic carbon of salicylaldoxime yielded the highest collector efficiency.

Jan 1, 1993

The reality is that in today's world almost half of nearly six billion people on the planet do not have access to commercial energy and the services it brings. Based on UN projections, in 30 years time there are likely to be nearly three billion more people in the world, over 90 per cent of them in countries which are already economically poor. The World Energy Council (WEC), through its 102 member countries, monitors trends and developments and projects future trends. WEC is a non-governmental international body representing all forms of energy and is committed to the sustainable use of energy for all mankind. This paper is based on WEC studies and papers presented at its many conferences and congresses worldwide. Primary energy demand growth is dominated by the developing countries over the next 30 years. The world energy mix is projected to change very little over the next 30 years. Fossil fuel supplies (ie coal, oil and gas) are likely to decline from 77 per cent to 73 per cent, nuclear energy may grow from five per cent to six per cent and renewable energy sources (eg hydro, solar, geothermal, wind, tidal and biomass) could increase from 18 per cent to 21 per cent. World energy consumption is expected to grow by over 50 per cent over the next 30 years. The paper reviews changes in energy demand in the world, particularly in the Asia/Pacific region. Environmental issues are covered, as are developments such as solar energy from space and the status of renewable energy forms. Agendas for action to achieve change are also reviewed.

Jan 1, 1997

The process of resource estimation of large precious metal deposits is illustrated by reference to major deposits now being mined or developed by Placer.The estimation procedure commences with building an appropriate model of the mineralization and proceeds through steps of data validation and geostatistical studies. It is important that the geologists most familiar with a deposit be involved with all stages of the estimate, and also prepare a manual estimate used to validate the kriged resource.Resource estimates are major exercises taking many man-months of work. The most time consuming part of this is usually construction of an appropriate three dimensional geological model. The data base for the resource calculations must be complete and checked for accuracy. The most appropriate estimation method must be selected.

Jan 1, 1990

By Wright S, Jorgensen F. R A

The reaction between lead sulphate and a number of base metal sulphides (galena, sphal- erite, chalcopyrite and synthetic pyrrhotite was studied as a means of desulphurizing lead sulphate containing fumes and residues to levels acceptable as ISF feed. The reactants were mixed with 50% zinc oxide to act as a "basket" to contain the molten products of the reaction and pressed into small briquettes 20 mm in diam. Factors such as temperature, time and the composition of the atmosphere were investigated. Using the PbS/PbS04 system as an example it was shown that the reaction became rapid above 800¦C and that both sulphur dioxide and oxygen in the atmosphere were detrimental to achieving low sulphur in the product. In an inert atmosphere all the sulphides when roasted for 1 h at 1000¦C gave results corresponding to the elimination of more than 95% of the sulphur in the reactants. Leach plant residues were considered for use as the "basket" material. It was shown that the residual sulphide and sulphate components of the residues underwent similar reactions to those experienced by the pure systems.

Jan 1, 1987

The cost-effectiveness of blasts involving radiating blastholes is cur- rently restricted in the following ways. (a) Significant percentages of potential explosion energy are not being liberated; the collar sections of some charges are being dislocated and/or desensitised by the detonations of adjacent earlier-firing charges. (b) If the minimum charge spacing is too small, detonation of an early- firing charge can initiate an adjacent charge sympathetically, thereby eliminating the benefit of any intended inter-charge delay. (c) The overall distribution of energy is poor. Appreciably better fragmentation would be achieved if current drill- ing patterns were to be replaced by staggered fans/rings having a toe spac- ing : burden ratio of about 4 : 1. This wide-spaced pattern would enable a higher percentage of the potential energy to be released, would reduce the incidence of sympathetic detonation and would provide a superior overall distribution of this liberated energy. If improved fragmentation is not required, the proposed fan/ring design should allow a significant expansion of the blasthole pattern with consequential cost savings in drill- ing, explosives and initiation.

Jan 1, 1988

By Sorokin M. L, Komkov A. A

Flash smelting of nickel sulphide concentrate has been practiced at WMC's Kalgoorlie Nickel Smelter for 20 years. The mineralogy of the concentrate from the original mines was particularly suited to this process. However, taking a strategic view, potential new processing routes should be fully evaluated as possible replacements for the current technology. The Vanyukov process has been under development in Russia for the past 40 years and has been successfully applied on a large scale to the smelting of copper concentrates, at two locations - Norilsk and Balkhash. The potential for the application of the Vanyukov process to the smelting of nickel concentrates offers a number of processing advantages, including smaller reactor and decreased dependence on fuel oil. This paper reports on preliminary investigations into the application of the Vanyukov process to the smelting of nickel concentrates. At this stage the investigations are limited to semi-quantitative comparisons and modelling studies.

Jan 1, 1992

The first geological maps of parts of Australia were produced in the 1830s and 1840s, many being for purely practical purposes, such as indicating the occurrence of coal, iron and other essential materials. Mineral location maps were also first made about the same time.More systematic geological mapping commenced in the 1850s when large parts of New South Wales and Victoria were studied in government-sponsored surveys by geologists such as Samuel Stutchbury, Alfred Selwyn and Reverend William B. Clarke. Their work coincided with the opening up of most of the major goldfields of eastern Australia, which led to the establishment of Departments of Mines in the separate Colonies (later States within the Commonwealth of Australia).A few companies employed consultant geologists at this time, and the mapping by Frederick Odernheimer is particularly notable. Geological study of Australian ore-deposits and mineralisedareas was influenced by the continental European geological ideas of men such as Odernheimer as well as by those from England. Both geological and mineral maps were a feature of Colonialdisplays presented at major international exhibitions during the second half of the nineteenth century. The maps accompanied rock and mineral collections which showed the known and potential mineral wealth of the Colonies. Such displays raised interest in the potential for development amongst government officials, entrepreneurs and investors in Australia and abroad.By the 1880s most of the Colonies had produced basic geological maps, and several maps of the whole continent had been published. Although systematic mapping of the continent become a reality only in the 1950s, the nineteenth century geological and mineral mapping formed the basis for the development of the major coal, artesian water, and metalliferous mining regions of Australia.

Jan 1, 1990

According to the temporal and spatial distribution of regional metallogenesis, the Pacific Rim can be divided into four global metallogenetic systems. The Asia-Australia W-Sn metallogenetic belt is the typical representative of intracontinen- tal metallogenetic systems. This belt resulted from Mesozoic and partly pre-Mesozoic tectonic magmatism, mainly re- lated to S-type granite of crustal source, that was generated by collisional orogeny combined with oceanic subduction in intracontinental and continental margin settings. Based on the concept of metallogenetic series, there is a group of min- eralised ore types showing a definite spatial and temporal distribution from endogenetic to exogenetic. These metalloge- netic series are widely distributed in the Asia-Australia W-Sn metallogenetic belt, and are well developed in Southeast China. Five metallogenetic series and two petro-minerogenesis evolution models have been established according to their tectonic settings, various types of granitoids and metallogenetic evolution.

Jan 1, 1995

By J Garritsen, P F. Wells, M Xu

IncoÆs Clarabelle mill currently processes ores from eight mines in the Sudbury basin area in Ontario, Canada. The ore from the Garson mine contains a much higher concentration of arsenic than the other ores. Adding this ore into the feed to the mill has resulted in an increase in arsenic content of the Cu-Ni bulk concentrate to a level that significantly affects the smelter operation, and more importantly the efficiency of Cu-Ni separation in the Matte separation plant. The arsenic occurs mainly as gersdorffite (NiAsS), with a small amount being in the form of cobaltite (CoAsS). Extensive laboratory tests on depressing arsenic in Garson ore flotation have been conducted and two reagent suites have been identified as effective arsenic depressants. One is the so called MAA depressant which is a mixture of magnesium chloride, ammonium chloride, and ammonium hydroxide. This reagent combination was reported to depress other arsenide minerals such as arsenopyrite (FeAsS) and enargite (Cu3AsS4). However, in this study for the first time it has been shown to have a depressing effect on gersdorffite. The other reagent suite, a mixture of triethylenetetramine (TETA) and sodium sulfite, that has been reported as an effective pyrrhotite (Fe1-xS) depressant in pentlandite ((NiFe)9S8) flotation, has not been reported as gersdorffite depressant before. The effectiveness of both reagent suites is more pronounced when the arsenic minerals are oxidised through pulp aeration or the addition of hydrogen peroxide. With a flow sheet consisting of a magnetic separation, rougher- scavenger flotation, followed by regrinding and cleaning of combined magnetic and scavenger concentrate, the arsenic recovery to the final Cu-Ni bulk concentrate was reduced from 73 per cent in baseline test to less than 30 per cent with either reagent suite at no decrease in nickel recovery. The TETA/sulfite reagent combination has the advantage over the MAA suite in that pyrrhotite is also depressed, rather than being activated, and the copper and nickel concentrate grades are therefore increased.

Jan 1, 2005

By Filmer AO

In contrast to the '50s and '60s, the period of the '80s and '90s seems likely to have low growth in demand but much greater levels of technological change. In such a climate there will be pressure on costs, productivity will continue to rise and competitiveness will be closely associated with maintenance of the most effective technology. The penalties for inappropriate investments, whether short sighted or mistakenly based on a particular view of the future, will be greatly enhanced. Accordingly, there will be a need for significantly improved anticipation of technical change and thus for better planning. Study of the funding and direction of the world's R&D effort can provide a useful input to the planning processes within industries and individual firms. Such a study also suggests some insights into the characteristics of those countries which have achieved substantial growth and high standards of living over the past two decades. These characteristics may offer significant reminders for our own development. The particular implications for the Australian minerals industry include the need for direction that is sensitive to changing market requirements and customer practice. This is not simply "more of the same." In particular it appears essential for both basic and applied R&D to provide a sound basis for the purchase and ongoing development of the new technology required to achieve international Competitiveness.

Jan 1, 1986

The known coal resources of South Australia are either of poor quality, or expensive to extract, or both. Export quality coal occurs only at great depth in the remote north of the State; the balance of the State's coal resources are suitable only for local electricity generation. Currently there is only one coal mine in the State, at Leigh Creek. This provides fuel for approximately 34% of the State's electricity generation, the balance being fuelled by natural gas. In the near future, new fuel sources must be developed to augment diminishing supplies of natural gas, and to cater for increasing demands for electricity. The South Australian Government has determined that future electricity generation will be based on the combustion of local coals. The geological and geographical environment of the known coal deposits and the quality of these coals are such that the most up to date and innovative technology must be applied to both extraction and combustion processes. The Government, the Electricity Trust of South Australia, and several Australian and overseas companies have embarked on an extensive research and development programme to ensure that these otherwise useless resources can be developed to the benefit of the State.

Jan 1, 1987

IN carrying out experiments to determine the amount of metal taken away by fume or fine dust the apparatus used requires to be strong and compact, as it is generaIIy necessary to work on a staging fixed at considerable distance above the ground and against a smoke stack or flue. It is essential that the test be carried out at a part of the stack welI away from any bends, to prevent eddies. The method described below has been used for estimating the dust losses from Dwight & Lloyd sintering machines, antimony drossing furnaces, pot sintering trials, etc., and has been founc! satisfaetory. It is welI to bear in mind that the longer the period over which dust coIIection is extended, the more valuable the result is likely to be. The rateof aspiration of the gases through the apparatus is kept as regular as possible by changing the filter thimbles frequently, and the rate of flow should correspond closely with the rate of flow of the gases up the stack.The apparatus required for carrying out a test is as folIows :-{a) Thermometers : two are required, one for taking the temperature of the gas in the stack and one for giving the temperature of the gas in the aspirating drum. If the temperature in the stack is over 400° C., it is advisable to use a pyrometer such as the "Bristol" the couple being standardized before use at about the temperature of the stack.(b) Pilot Tube: The foIIowing sketch (Fig. 1) iIIustrates the principle of the pitot tube. The readings are to be taken in a straight flue, or stack, preferably 20 diam. away from any bend. A, which is open, faces the air current and...

Jan 1, 1922

By Rynn J. M W, Paynter A

Recent studies by the authors have concerned themselves with assessing the earthquake risk to north-eastern Australia, based on available historical earthquake data for the area. There have been several significant earthquakes (Richter local magnitudes of the order of 6) concentrated in the Wide Bay - Burnett region in central eastern Queensland, although none of these has occurred close to a significant centre of population or development. Using derived average acceleration attenuation relations and world-wide data on earthquake-induced damage as a basis, conditions under which earthquake-induced liquefaction may occur have been investigated and presented in graphical form. Historical earthquake data for north-eastern Australia have been overlain on this graphical presentation and it has been demonstrated that the Wide Bay - Burnett region, in particular, may in the past have been on the verge of earthquake-induced liquefaction, where ground conditions are susceptible. When this is viewed in the context of the rapid growth in population and development in this area over recent years, the risk can no longer be ignored with impunity.

Jan 1, 1990

The structure and tectonic setting has had a strong influence on gold mineralisation at the Porgera gold deposit. Here, the structural controls on the mineralisation at Porgera are discussed and placed in a regional tectonic context. The Porgera gold deposit is related to the emplacement of the Porgera Intrusive Complex. Prior to intrusive emplacement at Porgera, Papua New Guinea was affected by a major fold and thrust episode which occurred in response to arc-continent collision in the Late Miocene. After crustal shortening the region experienced a relaxation of compression which is expressed in the deformation accompanying mineralisation at Porgera. The first stage of mineralisation (stage I) is hosted by extension fractures, and is spatially associated with exposed intrusive stocks. A later episode of mineralisation (stage II) is hosted by the faults and fractures of the Roamane Fault Zone, which was active as a dip-slip normal fault during stage II mineralisation. Therefore a change in the tectonic environment from shortening to extensional tectonics can be seen at Porgera before and during mineralisation. Rapid fault-slip during stage II mineralisation may have aided high-grade gold mineralisation by subjecting hydrothermal fluids to changes in pressure, temperature, fluid-fluid and fluid-rock interaction. Uplift to form the highlands of Papua New Guinea occurred after mineralisation and was largely complete by 4.0 Ma.

Jan 1, 1995

The proportion of coal production from underground operations in Queensland, is likely to increase in the future. A portion of this increase will come from mines working under farming areas. The degree of compatibility between underground coal mining operations and farming is examined. Two case histories are considered in detail. These relate to farming areas in the Moura and Emerald districts. Mining the Moura, area has been undertaken for the last two and half decades, while in the Emerald area, large scale underground coal mining is currently being planned. Interference to watercourses and water harvesting programmes, damage to crops, and ponding in cultivated areas have been experienced in mining areas. With expansion of underground mining in farming areas, the principle areas of likely conflict are the effects of surface subsidence on irrigation and erosion control structures. Other potential problems that may arise in particular circumstances include reduction in availability of water for harvesting, pollution, surface cracking and damage to surface structures. Finely textured soils and erratic and violent rainfall patterns make farming in central Queensland particularly vulnerable to severe soil erosion unless strict precautions are taken. Soil erosion control is an essential part of farming. Contour banks are used to ensure that runoff velocities are suitably low. Where steep slopes are encountered, grassing is the most effective way to prevent erosion.

Jan 1, 1987

The object of this paper is not to describe any particular type of engine in close technical detail but rather to give a general picture of past and present practice in this important section of the industry. The subject involves the study of almost 600 years of coal mining history which has fluctuated from stagnation to extremely rapid progress.Up to the year 1300, coal was obtained from outcrops and exposed beds, but this easily worked source soon gave out, so by that time shafts had to be sunk to the coal seams, and coal mining proper commenced its career.These early shafts were very shallow, and winding equipment was not a matter for much concern. Raising coal was generally achieved by human labour, which was called "coal bearing." Coal was loaded into baskets. strapped to a man's back, and carried from the underground workings to the pit bottom. The unfortunate individual then climbed ladders to the top of the shaft, unloaded the basket, and descended the shaft for the next load. Men, women and even children, were employed as the mine expanded, and were generally bound to the colliery for life, performing daily work which would now be regarded as slavery. This primitive method of raising coal to the surface was slow, inefficient and highly dangerous, yet for want of a better method it continued until in 1602 it isrecorded as having been abolished in Wales, one of England's great coal districts. It was not until 100 years later, however, that it was abolished in the northern coalfields, and the colliers were freed forever from their dreadful life.WINDLASSThe first step towards winding coal was the introduction of the windlass. This was similar to the common windlass used over a well, and was operated by man power. The...

Jan 1, 1945

By Kuruppu M

Geotechnical design plays a key role in mine design. A proper geotechnical design provides a safe working environment and facilitates efficient mining operation. There are mainly three design approaches: (i) judgmental, based on observational and experiential facts, (ii) empirical, based on empirical design formulae; and (iii) analytical, incorporating numerical analysis. Most design applications are based on the design methods one and two as mentioned earlier. However, complexities arise in deep underground mining operations and deep open pit mines. These complexities and difficult geological environment introduce more uncertainties and simple empirical formulae would not be adequate as a design tool. These situations require numerical modelling and analysis of the design problems including interpretation of the results obtained from the analysis. There are several tools available for performing the numerical modelling and analysis. A brief review of the available tools is provided. The authors selected ANSYS (a general purpose finite element analysis tool) for use in mining geomechanics and geotechnical design. This paper includes several examples demonstrating the applicability of this software in designing mining structures. The authors hope that the design examples will demonstrate the use of the numerical modelling and analysis applications in excavation design.

Jan 1, 1995

The Mt Keith Operation, 90 kilometres north of Leinster in the north-eastern Goldfields of Western Australia, was commissioned in October 1994. Based on a large tonnage, low-grade nickel sulphide orebody the plant was designed to produce 28 000 tonnes of nickel in a high-grade 20 per cent nickel concentrate. Following a successful and rapid start-up the operation is currently expanding to a throughput of ten million tonnes per annum (mtpa) ore and an annual production of 42 000 tonnes of nickel. This paper provides an overview of the Mt Keith Operation from commissioning to its present operation and Expansion.

Jan 1, 1996