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This talk was delivered in Kalgoorlie in April this year, to the Kalgoorlie Branch of The Institution of Engineers, Australia. We believe it is of such interest to members of our Institute and readers of this publication we believe it important to extend the audience who have the opportunity to read it. An edited version follows:"Why should we be so concerned about Mining Related Education; after all is said and done, the mining industry is not a great employer of persons?"The mining industry is capital rather than labour intensive. It employs only 2.7 per cent of the national workforce. However; the minerals industry is Australia's major exporter accounting for over 40 per cent of the nation's total export of goods.In Western Australia the value of minerals production in 1985 was about $5,000 million and consequently mineral exports accounted for about 53 per cent of the total value of overseas exports from the State. The diversity of the mining industry is also worthy of mention and produces iron ore, alumina, gold, nickel and mineral sands. That apart, our potential to become a major producer of diamonds, rare earths and petroleum products is considerable, not to mention base metals (copper, lead and zinc) and uranium.Our mining industry is of national importance and contributes in excess of 30 per cent of the total value of Australian overseas trade. Although the mining ind ustry does not employ many people, the people it employs contribute very much more, per capita, to the wealth of the nation than do employees in any other sector of our economy.No-one would deny that during the 20th century Australians have depended on the export earnings from the sale of relatively unprocessed agricultural products and more recently the sale of relatively unprocessed minerals for their standard of living.Not surprisingly, therefore, our economy is highly vulnerable to unstable world commodity market prices.The slump in trade we are currently experiencing (in first quarter 1987-Edition) was brought about by the over supply of the raw materials we produce. However, the recent downturn in world market prices is more serious than previous slumps because in part it is due to technological advances 'in other countries which could have a permanent effect on the world trade of primary products.

Jan 1, 1987

By Jephcott S

The McArthur lead-zinc-silver deposit is of the stratiform type. It consists of a mineralized bituminous shale sequence containing some tuffites, numerous graded beds and isolated slump breccia horizons. The principal sulphides; pyrite, sphalerite and galena, are essentially restricted to the shales and the genetically unrelated turbidites contain only minor mineralization. The geochemistry of the deposit has been investigated with respect to the stratigraphio column and mineralogy of the sediments.

Jan 1, 1980

Following the preparation of tantalum oxide and carbide (1) an investigation of the details relating to the production of tantalum metal powder was planned. From the literature (2) it was evident that tantalum could be produced either by reduction of potassium tantalum fluoride with an alkali metal or by electrolysis of a fused salt mixture containing a tantalum compound. The latter method appeared to be the more suitable and, as there was considerable divergence of opinion in the literature as to the nature of the reactions involved, it was decided to study the electrolytic process. The ultimate aim in any case was to produce tantalum pOWder for use in an investigation of the problems relating to the preparation of consolidated tantalum.FACTORS GOVERNING ELECTROLYSISAfter a few preliminary exploratory electrolyses several factors which needed amplification were revealed. These will be mentioned before the details of the electrolysis experiments are given.COMPOSITION OF THE BATHWithout the knowledge gained in the preliminary experiments it would be thought that the best material for the bath would be that one which underwent electrolytic decomposition. Consider what at first appeared the most likely - namely - potassium tantalum fluoride. The melting point of K2TaF7 was determined to be 630°C with volatilization and decomposition taking place at that temperature so that it would not have been very satisfactory.

Jan 1, 1946

The treatment of mixed lead carbonate and lead sulphide concentrates at Mount Isa presents a problem which is unique ,in the lead smelting world; a problem whose solution is far from simple, and is not yet complete. Two years of study under plant conditions have definitely proved, however, that a most satisfactory sinter can be made in a single-pass roast.The object of this paper is to present a brief record of the development of the single-pass roast and a resume of current practice in the smelting plant. The sintering operation is discussed in greater detail, as it is upon this phase of the work that every item in the smelter operating programme depends.The smelter, to-day, presents a very much simplified layout, equipped for economical, straightforward operation, requiring, however, very careful and constant supervision, due to the extreme delicacy of the sintering operation and to the rapid and wide variati9n in the nature of the concentrates which are to be handled.

Jan 1, 1933

The preamble to the mining Act sets out that such Act is to provide for the encouragement and regulation of mining within the State of Queensland. This paper will attempt to follow the legislative path of such aim and in particular to show what part Mining Wardens play in the administration of the Mining Act.The Mining Act empowers the Governor in Council to constitute Mining Districts and Mining Fields and to appoint any duly qualified officer of the Public Service of Queensland to be a Warden or a Mining Registrar. As a matter of practice Stipendiary Magistrates who hold office in the major centre within a Mining District are appointed Wardens and Clerks of the Court are appointed Mining Registrars. In some districts where there is no Stipendiary Magistrate the Clerk of the Court is appointed an Acting Warden with all the powers of a Warden. Every Warden so appointed is a Warden for the whole State.To achieve impartiality Section 74 of the Mining Act provides that a Warden shall not hold or be entitled (directly or indirectly) to the benefits of any share or interest in a mining tenement or mining venture and provides a penalty of $1000 or imprisonment for six months or both, for contravention of such section.

Jan 1, 1986

The reduction in the number and duration of machinery and equipment failures is an important source of economical efficiency enhancement in the Polish coal mining industry.Non-dismantling methods have been thus developed to evaluate the technical state of machines. Among these viroacoustical methods are the most effectively employed. Two-directional organisation of the testing can be chosen, such as periodical and continuous inspection. The monitoring methods for ball bearing, rope tension uniformity, longwall shearers, main fans and shafts installations etc. Instrumentation for monitoring measurements are either of intrinsically - safe or explosion - proof construction, which enables using them in a gas-hazard atmosphere. The development of these procedures has led to the trials to insert the diagnostic methods into the organisational scheme of a coal mine.

Jan 1, 1991

Diamonds occur in N.S.W., Victoria and north west Tasmania. Diamonds from different areas appear to have their own characteristics, lending weight to the suggestion that three or four different sources (different in location and age) have produced the diamonds found in alluvials at quite a number of locations in Eastern Australia. Explorers for kimberlites in Victoria must overcome a number of field difficulties. The writer's approach attempted to find exploration targets by literature search, noting unusual garnet occurrences, and by relating records of diamond occurrences to described mining activity. While the records are biased towards gold, the study did lead to a pipe, located well away from known diamond-bearing alluvials. Core from one test hole has shown this intrusive to include an alkaline ultramafic breccia with many kimberlitic affinities - a breccia containing mantle-derived minerals, but not a true kimberlite. (A detailed rock description is appended to this paper, but is not the purpose of the paper.) This result enhances the possibility that kimberlites may occur in Victoria, on or near large scale faults or grabens. The depth of fracture penetration may have been different

Jan 1, 1979

By S Brochot

During the development of a mining project, samples are taken for metallurgical tests. The sample can be a composite sample made of material coming from a selection of various drilling products or a sample coming from a mining test. This sample can represent several tonnes of material which are analysed and split to be used in various tests.In the current case, a composite sample is dedicated to semi-autogenous grinding (SAG) pilot plant tests. The property of interest is then the size distribution of the material. The sample is mixed and a subsample is taken to measure the size distribution which is considered as the feed size distribution. Then the remaining material of the sample is divided in several subsamples for batch grinding tests at different operating conditions. The product of each grinding test is then analysed to measure its size distribution.The grinding performances are analysed at the light of the measured size distributions for feed and product. But what is the accuracy of the measurement of these size distributions? What is the variability of the feed knowing each feed is just a subsample of the initial sample?The Pierre Gy theory of sampling answers these questions.The current paper presents, through a real example, the calculation of the measurement error of the size distributions and the variability of the feed between the different tests. The uncertainties of the grinding performances are then calculated and their impact on the results interpretation is then analysed.CITATION:Brochot, S, 2012. Sampling for grinding pilot plant test - the effect of size distribution variability, in Proceedings Sampling 2012 , pp 127-134 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 21, 2012

It is a sad commentary on human nature that for every successful, unscrupulous entrepreneur you need a multitude of incautious, greedy investors. One wonders whether is will be ever possible to completely protect investors from their reckless gambling instincts, which are so widely encouraged elsewhere in society.

Jan 1, 1989

By L Köresaar, J Moilanen

With lower and increasingly variable Fe grades in iron ore resources, the monitoring of Si, Al, Mg and other light elements to meet quality requirements is gaining importance in the iron ore beneficiation industry. The high cost per manual assay and associated manpower requirements often limit the frequency of shift composite samples and laboratory assays. Furthermore, the shift composite assays represent past performance of a plant but are not useful for immediate reactions to feed variations, detection of equipment malfunctions or process control. Automated online analysis of light elements radically reduces the cost per assay and provides repeatable, timely data for process analysis, control and optimisation.A light element online slurry analyser, based on laser-induced breakdown spectroscopy (LIBS) optical emission technique, will be presented. This paper discusses the analyser design for the iron ore industry and also reviews the performance of the analyser against the manual laboratory. Additionally operator safety, user friendliness and maintenance requirements are discussed.A case study will also be discussed in this paper. The sophisticated measurement technique has been implemented in an industrial automated analyser and sampling system to allow for slurry measurement for up to 12 sampling points. However, careful selection of the sampling points and implementation of the sampling system is required for smooth operation.CITATION:Köresaar, L, Timperi, J and Moilanen, J, 2015. Optimised process control in iron ore via online analysis of light elements, in Proceedings Iron Ore 2015, pp 511–518 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By M A. Rhamdhani, R Z. Mukhlis

Removing the ledge formation in the Hall-Heroult cell during the electrolysis process may significantly reduce the energy requirement of the aluminium production process. In the absence of the ledge, however, the sidewall-material types become heavily restricted since the cryolite is very corrosive at the electrolysis temperatures. This paper study the corrosion behaviour of sintered nickel ferrite, nickel aluminate, and magnesium aluminate refractories (as possible candidates for sidewall material) in molten aluminium and cryolite melts with various alumina content at 980°C. Immersion tests of refractories with various porosity were conducted to assess the suitability of the refractories in the corrosive environment of the electrolysis cells. Microstructural change of the refractory after immersion were analysed using secondary scanning electron microscopy (SEM). Sampling of the melts were taken at 0, 10 min, 30 min, and each hour up to 6 hrs, and subsequently analysed by Inductively Coupled Plasma (ICP) spectroscopy. Based on the projected concentration of the refractories constituents in the melts, it was predicted that the corrosion rate of NiFe2O4, NiAl2O4 and MgAl2O4 in cryolite with 11 wt per cent Al2O3 were 461 × 103, 1.03 × 103, and 798 × 103 cm/a, respectively. Much lower corrosion rate of 2.3 cm/a for NiFe2O4, 2.6 cm/a for NiAl2O4 and 0.3 cm/a for MgAl2O4 were predicted if the refractories in contact with aluminium melts. Erosion played an important role in the corrosion as the concentration of the refractory constituents in the melts were beyond its solubility limit. It is therefore crucial to increase the densities of the refractory and improve its wetting characteristics.

Aug 21, 2024

Process variables in flotation circuits are outlined with a view to producing mathematical models of circuits. The nature of the kinetics of flotation are discussed and the effect of process variables on the kinetics considered. An approach for a possible model is briefly outlined.

Jan 1, 1971

The development of present methods of pillar extraction has evolved from the very earliest of hand mining operations which were limited in scope by venti- lation and transport considerations. Conservation and safety considerations also have led to the current shortwall operations with conventional equipment and powered supports. The shortwall methods have had significant effects on safety, costs, con- servation, flexibility, and other aspects of pillar extraction. The present stage falls short of the ideal but is some guide to prediction in what direction may lie the ideal methods for the future.

Jan 1, 1974

The development of the Moura Coal Preparation Plant is described, commencing with the first'stage of the plant commissioned in 1963. The subsequent expansion stages are traced through to October, 1973. The plant has undergone frequent stages of expansion and modification and this process is continuing. The development programme for 1974 is described as proposed in late 1973. The characteristics of the Moura and Kianga field coal seams with respect to washability are summarised and some comment is made on the blending of these coals prior to washing, to ensure production of export grade coal within specification.

Jan 1, 1974

By Thompson IR, Solomons SS

Underground mining with the cut and fill method has been declining during the past decade or so, being replaced mostly by sublevel open stoping methods. During 1983 the Australian Mineral Industries Research Association Ltd. (AMIRA) commissioned a review of the method, with the aim of compiling the state-of-the-art, indicating future trends and recommending topics for research that would be needed to support this future mining. Mines using the cut and fill method in Australia and three other countries were visited to compile current practices and expected developments.Cut and fill is mostly used where geological and ground conditions are unsuitable for open or caving methods. These range from narrow, irregular orebodies to wide, massive orebodies where pillars are retained in ore. There is significant potential for improvement and further development of the method. It may then be used in a broader range of conditions and for orebodies that may not otherwise be viable to mine.

Jan 1, 1985

By Giles D, Wegmann D

The Mt Todd Gold Project is located 42 km northwest of the township of Katherine within the Northern Territory of Australia. It is situated in the southeastern portion of the Pine Creek Geosyncline. The Batman gold deposit, the largest of several deposits at Mt Todd, hosts an identified mineral resource of 92.9 million tonnes (Mt) grading 1.4 grams/tonne (g/t) as at 31 December 1993. Host rocks at Batman are assigned to the Early Proterozoic Burrell Creek Formation, comprising greywacke and siltstone interbedded with shale. Gold mineralisation is associated with a very broad zone of sheeted and stockwork quartz-sulphide veins that occupy a corridor of intense brittle fracture and faulting. A conceptual model of formation involves the dilation of joints and micro-faults within overlying sediments during sinistral movement along a basement shear zone. Synchronous granite intrusion generated convective circulation of crustal fluids through the sedimentary pile resulting in the formation of auriferous quartz veins within favourable structures. The Batman zone of mineralisation is not directly related to fold structures which typify several other major gold deposits within the Pine Creek Geosyncline.

Jan 1, 1994

Knowledge of the hydrogeological setting of a mine forms an integral part of a mining operation. Groundwater impacts, initially, on mine feasibility. Then, on commencement of mining, it interacts on the operational components of dewatering, water supply, tailings leachates, mine wall stability, stormwater run-off, water disposal, impact on regional environment and mine closure planning. The recording of hydrogeological information is frequently overlooked during resource and reserve definition as well as during the course of mining when prime opportunity exists for the collection and collation of this data. In recent times, the exclusion of hydrogeological data has been exacerbated by use of high air pressure drill rigs that exclude water inflow. The recording of water data has been further inhibited by the use of computer coded drill logs that do not include the site geologistÆs or drillerÆs comments on drilling problems and observations associated with groundwater intersections. Geologists now infrequently directly supervise drill rigs, but visit the rig only intermittently to evaluate drilling progress. They do not see first hand drill performance characteristics at water make zones. Drill cuttings, as drill chips and cores, are now mostly logged away from the drill site so that wet sample locations, visual water flow evidence and verbal comments from the driller are not recorded. As a result, mine geologists now do not direct adequate attention to the delineation of lithologies and structures that store and transmit water. This paper provides examples of water sighting and recording techniques applicable to a mining operation. Examples are also provided where hydrogeological conditions have been disregarded with serious impact on the progress of mining. The recording of hydrogeological data should be maintained and formatted by the site geologists into a useful database for review as and when required by specialists in hydrogeology, geotechnical and mining engineering and the environment. The information can be coded by the site geologist for inclusion into the mine database. A groundwater dataset, compiled during the progress of field investigations, will save the considerable cost of re-drilling and hole re-entry testing which would otherwise be required to provide base level hydrogeological information required for progress of mining. Apart from working mine use, a hydrogeological dataset is a necessary component for planning mining closure and mine legacy conditions.

Jan 1, 2003

By Hunter W. H, Wilson I. P, Craig R. W

In September 1988 the Imperial Smelting zinc - lead blast furnace at Avonmouth England, was uprated from its then 52 week annual rated capacity of 90 000 tonnes/year of furnace zinc to 110 000 tonnes. In order to provide sufficient extra feed the sinter plant was likewise uprated in April 1989 by increasing the blowing rate of the sinter/acid plants from 100 000 to 120 000 Nm3/h, effectively a 20 per cent increase. In the 12 months after the uprate zinc production was only 85 000 tonnes. Two years after the uprate zinc production had increased to 100 000 tonnes, but it was not until January 1992 that a rolling 12-month zinc production of 110 000 tonnes was consistently achieved. This paper describes the problems encountered with the uprate and how they have been or are being overcome. It deals chronologically with events starting with the restart of the ISF at the end of 1988 and covers the following issues and their resolution: 1. Initial shortages of sinter due to an offset in uprate timing. 2. Greater difficulties in operating the larger furnace particularly on start-up, the greater tendency for iron production and serious slagging problems. 3. Coincidental timing of deleterious trends in slag chemistry. 4. Refractory problems in the furnace shaft and condenser. 5. Shortages of sinter due to commissioning problems with the wet gas and sinter tip end fans, and difficulties in obtaining sufficient sinter hardness. 6. Unrealised full benefits of the sinter-acid uprate due to a late change in design to dispense with sinter gas recirculation, but offset by successful use of oxygen. In a planned maintenance stop in September 1992 further improvements to the furnace design were carried out to resolve the refractory problems, and with improvements to the sinter plant the furnace zinc output capacity is planned to rise to a rate of 120 000 tonnes/year within two years.

Jan 1, 1993

By Brown N. R

This paper attempts to highlight some of the problems encountered in the economic exploitation of the deeper coal seams by opencast mining methods. The major cost elements of three methods of overburden removal are examined in relation to the overall cost of winning coal from deeper-lying coal seams. The three overburden removal methods examined are dragline stripping and two systems combining dragline stripping with shovels and trucks at varying depths of overburden. A dragline is, undoubtedly, the most cost effective system of overburden removal for depths of up to 30 metres but it is suggested that, when dealing with incremental overburden depths in excess of 30 metres, engineers should consider carefully the possibility of using a shovel and truck operation, or other system, to augment the use of a dragline.

Jan 1, 1986

Australian continental crust has accreted and consolidated by thirds: 1/3 during Archean time, 1/3 during Early to mid- Proterozoic time, and 1/3 during latest Precambrian to mostly Paleozoic time. The progression of orogenic systems and the crustal consolidations they represent seem not fundamentally different in basic orogenic processes from better known Mesozoic-Cenozoic examples in that accretionary, continental margin, collisional, and intraplate intracratonic inverted and/or reactivated systems are all recognizable in the tectonic evolution of Australia.

Jan 1, 1995