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By R A. Bearman

Recent demand pressures for iron ore should not distract from the longer term view that intense competition in the industry has demanded technological innovation of a high order. There is a long track record of successful innovation underpinned by a solid base of scientific research and knowledge. By comment on recent developments in trucks, comminution and direct smelting, this paper suggests that innovation is still a key attribute of the industry. The spending of the minerals industry on underlying science, however, is not particularly high. By looking at other industries we can ascertain that for step change technologies, it is particularly advantageous to have a solid base of science and technology underpinning developments.

Jan 1, 2005

At the LKAB, Iron Ore Mine, Kiruna, Sweden a preliminary investigation into the reliability characteristics of a fleet of load-haul-dump machines has shown that the hydraulic system is one of the most critical parts. Therefore, hydraulic system was selected for study and analysis through condition monitoring devices so that failure can be controlled or at least the failure consequences can be minimized.The hydraulic system has two different problems; one is that the contamination level is too high and the other is high temperature during operation. At high temperature, seals and tubes are a problem, because they stiffen due to carbonization, which leads to increasing leakage. The pumps and restrictions were responsible for the main temperature increase.

Jan 1, 1991

By Gomm SA

The Mount Tom Price Concentrator, which contains a heavy medium cyclone plant for beneficiation of the -6+0.5mm fraction of low grade iron ore, is described. Testwork was carried out on an opportune basis over a period exceeding twelve months, to evaluate the separation performance of the heavy medium cyclones. Plastic density tracers were used and ore samples were taken and analysed. The effect of operating medium specific gravity (S.G.) on the separation parameters, the iron grade of the sinks product, and the mass and iron recoveries were investigated. Also examined were the differences in perform- ance between particles of different size. The implications of the findings for plant oper- ation are discussed.

Jan 1, 1987

By Mandzic E. H

The Dome Mine of Timmins Mining company is located in South Porcupine, N.W. Ontario. The orebody being mined partially lies in the No. 3 shaft pillar. Stability analysis has been carried out to establish the influence of nearby mining on ground movement in the shaft vicinity. Mathematical modelling of shaft displacement has been done for stope layout at depths from 180-210 m and distances of 10-50 m from the shaft. Analysis indicated that ground displacement around the shaft is below 1 mm/m and one third less for cut and fill than in the case of open stope mining. The result of the investigation was later confirmed by cut and fill mining of this orebody.

Jan 1, 1986

Taxation is a major factor in evaluating mining project developments. The availability or otherwise of effective tax relief for project expenditures can have a crucial bearing on the decision to proceed with a project. The special position of the mining industry is recognised within the Income Tax Assessment Act (the "Tax Act") by special legislation, namely Divisions 10, 1OAAA and 10AA. The legislation both extends the scope of items which are eligible for deduction and affects the timing of deductions. Generally, the legislation separates expenditure into 3 categories: 1. Expenditure on exploration 2. Capital expenditure on the development and the running of the mine; and 3. Facilities used in the transport of minerals. Companies evaluating a project should carefully analyse their proposed expenditures, allocating them between these categories so as to identify potentially non-deductible expenditures and to determine the period over which tax relief will be Obtained.

Jan 1, 1983

Carbonation of reinforced concrete is a potential durability issue for vehicular tunnels. This is particularly the case where elevated carbon dioxide concentrations exist and when the design life is 100 years or more. The process of carbonation can result in loss of passive protection to embedded steel reinforcement and initiation of corrosion. Therefore, tunnel design needs to consider the potential for carbonation on internal surfaces and how design life can be achieved in severe environments. This paper examines methods for predicting carbonation and how deterioration can be mitigated through appropriate concrete mix design and construction practices.

Jan 1, 2008

The mathematical modelling of rock fragmentation by blasting is one of the most difficult and challenging problems of applied mathematics. Not only is complex mathematics required but there is incomplete understanding of the basic physics and chemistry involved. The possibility of getting the physical basis of a model correct by simple mathematical and experimental procedures is demonstrated for the novel process of fragmenting rock by high-pressure arc discharges. While the importance of obtaining the correct physical basis for a model is emphasised, high-pressure arc induced fragmentation of rock is shown to be a powerful laboratory tool for the study of blasting.

Jan 1, 1990

By E Villaescusa

This paper summarises research work carried out at the Western Australian School of Mines on mine backfill properties in the last few years. The fill properties presented relate to cemented aggregate fill and cemented tailings fill. Emphasis of these studies has been placed on the composition of backfill materials including aggregate particle size distribution, cement dosage and influence of cement admixtures. The unique features of the backfill research carried out at WASM during the last few years are the accomplishment of a study into the properties of large cemented rockfill samples by triaxial testing and the investigation of the properties of fill material made from highly saline ground water prevailing in the Goldfields region of Western Australia. Exploring different cost-effective binding agents for mine backfill was also carried out at WASM. Special effort has been put on the development of fill materials compatible with hydraulic and paste fills. During the process, specific methods and procedures for laboratory testing of backfill material have been formalised. The on-going backfill research on sample scaling is summarised and the future direction of WASMÆs backfill research focus is outlined.

Jan 1, 2000

By Peng S. S

Measurement of pressure distribution under the base plate of the Hemscheidt 2-leg 800-ton shield was performed underground for two shifts using 12 pressure cells installed in two rows, one each under each split base plate. Pressure distribution was uneven depending on contact condition. In general the highest base pressure occurred at 1/3 of the base plate contact length from the rear edge. The resultant was near vertical, and the pressure under the tail side split base plate was always higher than the head side. For comparison, pressure distribution on the canopy and under the base plate was also measured under controlled conditions at the USBM's Mine Simulator Testing Facilities in Pittsburgh, PA. A total of 45 tests were conducted under several simulated contact conditions. The results showed that the actual contact area is highly dependent on the compliance of the immediate roof and floor due to the sloped canopy tip and a base lifting device under the base tip. The loading distribution tends to change in magnitude and profile as the leg pressure increases. The base lifting device exaggerates the high toe loading on the base plate characteristics of this type of shield support.

Jan 1, 1992

By Piga P, Sammarco O

Ventilation and the environmental climate in the Campiano mine is the subject of this re- search. The mine is located in Southern Tuscany (Central Italy), a region where geothermal gra- dients are very high (three times the average gradient of the earth). The research produced interesting indications as to the influence of surface climatic conditions on the environmental parameters inside the mine. A close correlation has been found between dry-bulb temperature and humidity ratio of the air in the mine for dif- ferent metereological conditions and for differ- ent mass flow rate values. Variations in air enthalpy, caused only by the heat exchange with the rock walls during the flowing of the air through the mine, depends on the surface temperature values. Statistical analyses have been used to ex- press air enthalpy variations on surface tempe- ratures, on the variations of the humidity ratio that the air undergoes inside the mine and on the mass flora rate. The application in practice of the results will permit the identification of correct mea- sures to be adopted so that optimal microcli- matic conditions are produced in the mine.

Jan 1, 1986

By A Turichshev

The synthetic rock mass (SRM) approach for modelling jointed and veined rock has been at the forefront of caving geomechanics research for years. A well-constructed and calibrated SRM model can capture the full rock behaviour at a macroscopic scale. Traditionally, SRM technology employed bonded particle models (BPM) due to their ability to model rock’s response to loading without prior specification of behaviour. The SRM modelling process requires the BPM to simulate intact rock and the subsequent introduction of fractures or veins by changing bonding characteristics between the particles. However, bonded particle materials have difficulty reproducing both the compressive and tensile strengths of intact rock. This and other limitations of BPM have been the driving force in exploring the potential of grain-based (2D) and bonded block (3D) models (BBM).This paper reports on recent work exploring the applicability of both BPMs and BBMs in 3D to the modelling of intact rock. The advantages and limitations of both BPMs and BBMs are addressed based on the results of numerical simulations using the PFC3D and 3DEC distinct element codes. The preliminary results suggest that BBMs are better suited for simulating intact rock behaviour than BPMs. Ongoing work aims to better qualify the applicability of BBMs under different conditions. This has significant implications for our understanding of rock mass behaviour in a caving environment.CITATION:Turichshev, A and Hadjigeorgiou, J, 2016. Simulating intact rock behaviour using bonded particle and bonded block models, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 453–460 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

In Australia a social impact assessment (SIA) is generally required prior to the approval of a mineral resource extraction or processing projects as a part of the Environmental Impact Assessment (EIA) process. In recent years there has been increased attention on the adequacy of the SIA process applied in major project assessment. Most applications have focused on the impact identification process with little attempt given to the community negotiating power over how impacts will be addressed. The impact assessment tends to occur at a single point in time, with no subsequent re-evaluation or ongoing social impact management and monitoring process. The assessments rarely specify how responsibilities for impacts on communities may be apportioned between project proponents and government, and have been inadequate in dealing with cumulative project impacts. In Queensland, concern about these shortfalls have led to the release of the Sustainable Resource Communities Policy 2008 and requirements for social impact management plans (SIMP) to be developed for each resource development in the State. In this paper a 'pressure-state-response' approach to impact assessment is used to develop an 'impact-response-monitoring-evaluation' (IRME) framework that can be applied to ongoing evaluation and monitoring of social impacts. The framework is applied to coal resource developments in the northern Bowen Basin in Queensland to identify core requirements in a SIMP. The IRME framework is flexible enough to be implemented at various spatial and time scales, for the wellbeing of the local and regional mining and non-mining communities in Australia. The framework can be further examined in other mine developments and could be integrated with the existing mining or environmental protection acts.

Jun 1, 2010

THERE are few industrial and metallurgieal processes which do not require the application of heat energy, and the modern demand for increased working efficiency has resulted in attention being paid to temperature control as a means of ensuring fuel economy and more efficient plant operation. In general, mill accuracy required is not very contant in laboratory work, and few industrial operations are controlled to within less than 5° while in many cases greater limits are allowable. Almost every thermal property of matter has been suggested as a basis for the construction of pyrometers, but the thermo-electric type finds by far the widest application, and hence this paper will deal only with the principles, construction, and uses of this type of instrument. THERMOELECTRIC PYROMETRY.In the year 1821 Seebeek discovered that if the ends of two dissimilar metal wires were joined and one junction heated, a current flowed in the circuit, and the KMF (electro-motion force) set up could be measured by inserting a galvanometer at the cold junction. The phenomenon was not thoroughly investigated for many years, but, as the demand for high-temperature thermometers increased, several investigators, of whom Le Chatelier was one of the pioneers, successfully endeavoured to utilize the principle in pnometric construction. The couples which gave the most satisfactory results were discovered, improvements were made in material and design and the present-day type of instrument gradually evolved. The apparatus consists of three main parts, viz. (1) The thermo-couple itself of two dissimilar metal or alloy wires together at one end. (2) The leads which connect the terminal of the thermo-couple with the measuring instrument.

Jan 1, 1923

By Doxford CI, Perry AJ

Mining Lease 908, situated on Gorge Creek near its confluence with the present Cape River system, has been subjected to intensive recent exploration for alluvial gold.The gold is hosted by a buried palaeochannel, the Gorge Creek Lead and by an overlying remnant meander of the Cape River. The principal, if not sole, sources of gold within the Gorge Creek Lead are the northwest trending Great Australian Reef and Green's Specimen Reef systems which are situated on adjacent high ground. Lower grade gold bearing eluvial ground separates the reefs from the Gorge Creek Lead. The sources for gold within the old Cape River system channel (Canton Lead) are thought to be situated some distance upstream, one source perhaps being the Lolworth Diggings located 30 kilometres to the northwest.Exploration of previously "heavily dug" ground on both leads consisted of detailed geological mapping followed by the collection and treatment of bulk samples from eight costeans. The wash samples varied in size from 120 to 396 cubic metres. Treatment was undertaken through a commercial sized conventional wet screen and jig plant.

Jan 1, 1986

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

By Conway KM

The traditional role of Australian Consultants in project development has been until recently restricted to the provision of discrete packages for survey and engineering services during the feasibility, design and construction phases of a project. Management of such projects was the province of the owner/developer or his agent. However, Australian Consultants are now being con- sidered for an expanded role on resources Projects.

Jan 1, 1983

By James D, Dawson N

The alternate mineral dressing tech-niques for the production of ilmenite roaster feed from heavy mineral concentrate and the reasons for the selection of wet high intensity magnetic separation (WHIMS) at Richards Bay Minerals are outlined.Initial flowsheet studies were under-taken using laboratory scale equipment followed by on site pilot testing. Flowsheet development culminated with an extensive test programme conducted at Readings of Lismore in 1975.

Jan 1, 1986

By Walter GW

Rock mass classification systems for stable excavation design have been studied. The parameters which are important in such a classification system and those which should be included in a classification system formulated to predict explosive fragmentation behaviour are briefly reviewed and compared. There is significant overlap in the data requirements for excavation design and explosive blast de- sign. Recently there has been a trend to ob- tain some of the data required for excavation design by the use of both field and laboratory seismic investigations. The theory of seismic techniques is summarised and the results of seismic investigations carried out for excava- tion design are reviewed. On this basis it is considered that seismic techniques have the potential to be used for data collection prior to blast design. A programme designed to de- velop such techniques and which includes both field and laboratory experimentation is Presented.

Jan 1, 1978

The methods used by the Anglo American Corporation for analysis of long-term metal markets and prices are described. The principal factors affecting the relationships between production costs and metal prices are analysed. These are firstly the type of market, - speculative or consumer commodity, free market or subject to price control; and secondly the rate of growth of demand for the metal. It is shown that virtually all metals will have relatively low rates of demand growth for the foreseeable future, due to market saturation, increased economisation, substitution and product obsolescence. Metal prices have a clear dependance on production costs, however forecasting future costs is by no means simple; amongst other things, account must be taken of changing exchange rates, inflation rates, and the potential for operating more efficiently. The paper concludes by giving brief assessments of the long-term future for aluminium, copper, zinc, nickel and tin.

Jan 1, 1986

By S Jeon, K Aikawa, M Ito, A Kusano, I Park, N Hiroyoshi

In mineral processing of complex sulfide ores containing copper (Cu), lead (Pb), and zinc (Zn), flotation has been commonly used. Typical Pb mineral in the ores is galena (PbS), while some types of the ores contain anglesite (PbSO4). This article reviews our recent studies on the effects of coexisting PbSO4 on the flotation of complex sulfide ores, and a method to suppress the floatability of sphalerite (ZnS) in the presence of PbSO4 was proposed. Comparison of flotation experiments for different types of model samples showed that PbSO4 makes the separation of Zn from Cu difficult; that is, for the model sample containing PbS without PbSO4, Zn could be separated from Cu, while when the model sample containing PbSO4, Zn was recovered together with Cu as froth. Solution analysis and thermodynamic calculation suggested that Pb2+ was released from PbSO4 and reacted with ZnS to form PbS, acting as an adsorption site for the flotation collector, xanthate. This would be the main reason for high floatability of ZnS in the presence of PbSO4. As a method to suppress ZnS floatability for the ores containing PbSO4, a pre-treatment of the ores to remove PbSO4 prior to flotation was proposed. The results of model experiments using mixture of ZnS and PbSO4 showed that ~97 per cent of PbSO4 was dissolved within 30 minutes of pretreatment using ethylenediaminetetraacetic acid (EDTA) as extractant, and thus ZnS floatability was markedly suppressed. Moreover, Pb2+ extracted from PbSO4 during the pre-treatment could be recovered as zero-valent Pb by the cementation using zero-valent Fe as a reductant. The details of ZnS flotation in the presence of PbSO4 and the effects of the pre-treatment are discussed based on the results of surface analysis like XPS.

Aug 24, 2022