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The New South Wales coal industry is a highly mechanised well organised industry which has developed from an annual production of slightly less than 13 million tons in 1950 to over 33 million tons in 1969. Although continuous miners were not introduced into the mines until 1950, by Jillle 1969 the percentage of coal won by these units was 87.3. The paper describes mining conditions in the various coalfields of the State, their complexities and problems and how these have been dealt with. The introduction of fully mechanised long wall faces has presented a challenge which has been accepted and descriptions of systems in use are discussed. Major expansion of the industry is anticipated to meet the requirements of the growing Australian steel industry, for local power generation and to meet the increasing demands of overseas markets.

Jan 1, 1971

By D Sinclair

Sustainability will become a more stringent issue in mine planning over the next 40 years. The evidence of this is apparent in State and Commonwealth government policies now emerging in respect to water, green house gases, waste and other process emissions. The mining industry has developed policies such as æEnduring ValueÆ, which go some way towards establishing a framework within which mining can continue to be an underpinning strength within the Australian economy. However, the demands of new policies are directed at extending sustainability in ways that will change the way in which projects are implemented. This paper examines the nature of new policies aimed at water, energy and emissions, considering examples of where mining practices have or may change in order to meet new objectives in resource efficiency. Important issues will, as always, be the international price competitiveness of the mineral resources being produced but, where this is now devolved around mining and processing costs, these costs may in the future be strongly correlated to the nature and cost of local energy resources compared with those in Australia, the ability to mitigate and minimise water resource use and environmental impacts deriving from emissions and the veracity of competitor nations in meeting the same standards of performance in resource efficiency usage and in emissions control. As these systems bed down internationally mining in Australia will need to concentrate, amongst other things, on finding higher grade orebodies and on better technologies to release the value of lower grade ores. For our mining industry to remain strong, greater expenditure will need to be focused on these objectives. Finally, it will be important for the industry to remain vigilant and proactive in directing government policy development to ensure that practical objectives in mining are not curtailed unnecessarily through ignorance of mining market precepts developed over the centuries of mining operations.

Jan 1, 2008

The richer, shallower sapphire deposits of the New England region of New South Wales which have been traditionally mined by the small miner are almost worked out. Larger mining and exploration companies are replacing the small miner and exploring for the primary source of sapphire or lower grade alluvial deposits.   Although in recent years considerable exploration effort has been directed at locating the primary source, commercial exploitation of sapphire is still restricted to the working of alluvial deposits.   If the Australian industry is to compete against Asian and African producers it must use cost effective exploration, mining) processing and marketing methods.

Jan 1, 1990

By R Edwards

Greater efficiency of capture of minus 6 mm to fine micron size particles of free gold is achieved with the Knelson Concentrator. The development, principles of operation and recent innovations relating to this enhanced gravity concentrating device are described by the inventor, followed by a description of application and consequent economic benefits in low grade alluvial gold deposits by a large scale user of Knelson Concentrators in the Northern Territory of Australia.

Jan 1, 1990

When the HSE Act was introduced in New Zealand in April 1993, one of the prime aims of the Government was to signal to the industry. The Government's recognition of the employer as the key person responsible for safety and health in the workplace and to actively encourage employers to self manage the health and safety function. Because of the significant change in the philosophy behind the new legislation, and because of the inherently conservative nature of the mining industry, it has taken some years for both the industry and the regulators to reach the stage of considering the framework in which a controlled degree of self management can proceed.   In this paper, some of the issues relating to the legitimacy of the process are considered, some of the questions raised in the minds of those charged with implementing the legislation are discussed, and the views of some eminent authors are examined.   The latter part of the paper focuses on a programme called the Reduced Site Surveillance Programme, which grew out of Goal 2 of the New Zealand Mining Inspection Group's 5-Year Strategic Plan. The programme is described in some detail, and the criteria applied at each stage of the programme is discussed. The paper concludes with the author's expectations of the longer term outcomes of the programme.

Jan 1, 1997

The process of hydraulic transport through pipelines, worldwide well known for the transport of fine-grain solids is also being used to a greater extent in mining for the handling of primarily coarse-grain solid û water mixtures for the removal of, for instance û coal and waste mixtures after coal winning using hydraulic monitors, tailings for backfilling underground and washer tailings and flotation waste to the dump. A large-scale test unit was taken into service at the Bergbauforschung GmbH (Mining Research Company) in Essen-Kray, GFR, to further improve this technology. The unit was planned and built by Krupp Industrie- und Stahlbau of Duisburg in cooperation with Bergbauforschung GmbH. The paper deals in detail with the demands made on this test unit and the technical results obtained on it and with the planned experimental research work.

Jan 1, 1980

The profitability of gold placer mining operations is determined by more factors than many placer miners recognise until too late. This study is based upon field trips to examine the efficiency of mining and transportation of gravels to a wash plant by bulldozer and truck. At the examined open pit mining operations gravels were washed using water canons, derockers or scrubber trommels. The objective of this study was to determine the relationship between unit costs and power requirements for gravel mining and processing. The author conducted a number of time and motion studies at four open pit gold mines, including the Maly Patom Creek, the Nizhny Patom, the Taimendra Creek and the Kadali-Makit in the Bodaibo District, Irkutsk Region and collected and processed field data. As a part of the study significant correlations were determined and empiric regression equations derived between: power requirements (Ep) and unit cost (Cp) for gravel processing; and total power requirements (Et) and total unit cost (Ct) for gravel mining, transportation and processing. Based on the results of the study it was proposed to modify the current mining procedure methods and to replace water cannons at the Maly Patom Creek with a PPM-5 derocker. Introduction of the proposed technology resulted in 2004 in US$385 000 mining cost reduction at the Maly Patom Creek over a short-time Siberian mining season.

Jan 1, 2007

Quartz, adularia and clay minerals from low-sulfidation epithermal veins at Hishikari were analyzed for their oxygen and hydrogen stable isotope compositions to establish the source of paleohydrothermal waters. Positive correlation between Au-Ag and adularia: quartz ratio, the presence of quartz pseudomorphs of bladed calcite, and Au-bearing smectite and vermiculite is indicative, but not definitive, evidence for the control of boiling on ore mineralization. Oxygen isotope equilibrium temperatures between quartz and adularia are about 220¦C and average homogenization temperatures of fluid inclusions vary between 190 to 210¦C. The calculated d18OH2O and dDH2O values (from quartz, adularia and early smectite) are consistent with paleohydrothermal fluids that were a mixture of magmatic and meteoric waters, or alternatively, the values could derive from heated meteoric water which had undergone isotope exchange during circulation through basement rock. Overall, d18Oqtz values in veins increase toward the north, most likely reflecting palaeo-fluid flow (source).

Jan 1, 2001

By P Maillet, A J. Crawford, S M. Eggins

TheFiji Islands are remnants of a once continuous Solomon-Vanuatu-Fiji-Tonga volcanic arc (the Vitiaz arc), located at the boundary between the Indian-Australian and Pacific plates. They record a history of: (i)                  arc volcanism the late Eocene to late Miocene, (ii)                an extensive magmatic response to arc rifting (5.5 - 3.0 Ma) during which volcanism was dominated by shoshonitic to tholeiitic basalts, and as rifting continued, (iii)               a transition from arc to intraplate volcanism.   The Hunter Ridge-Hunter Fracture Zone separates the inactive South Fiji Basin from the actively spreading North Fiji Basin, and has been considered to be a transform zone, almost parallel to the motion vector of the Australian plate. However rocks dredged during the 1993 æAlizeÆ cruise, from along the northern part of the Hunter Ridge are typical arc tholeiites, and therefore demand that subduction has occurred beneath the Hunter Ridge sometime during the last ~5 Ma. The Kadavu Island group, south westernmost Fiji, lies at the north-eastern end of the Hunter Ridge-Hunter Fracture Zone, and possibly results from oblique subduction of South Fiji Basin oceanic crust, which may have accompanied the anticlockwise rotation of Fiji during opening of the North Fiji Basin. These islands consist dominantly of 3.4 - 0.5 Ma old medium-high K andesites and dacites, with many traits typical of subduction-related volcanics, ie predominance of intermediate members (55 - 65% SiO2) no Fe enrichment, TiO2<1%, and negative Nb-Ta anomalies. These features contrast strongly with volcanics from elsewhere in Fiji around this time, where volcanic centres produced Om-like intraplate olivine basalts. The Kadavu Islands become gradually younger to the southwest, and show a significant decrease in K2O with time. The north easternmost islands (Astrolabe islands) containing the oldest rocks (~3 Ma) have shoshonitic affinities and are considered to be of similar age and composition to the youngest shoshonites found elsewhere in Fiji.

Jan 1, 1995

A combination of the needs of business, employee desires and safety and health considerations is stimulating increasing attention to the time spent by people at work and the timing of that work. Particularly we are seeing: - innovative work schedules for 24-hour mining businesses; and - response from industry to accommodate the needs, even the desires, of employees in return for systems which are more productive and more capital efficient. There appears to be an evolutionary trend for business management to become more sophisticated and responsive to the need for achieving close to best cost work schedules to sustain continuous improvement. The underlying motivating forces driving this trend for improved techniques in organising attendance at, and time spent at work, is the seemingly inseparable combination of technological advance and ever-increasing accumulation of capital. The mining industry has not remained untouched by this thrust for ever-increasing need for best use of labour, to adopt advances in technology and to provide attractive opportunities for putting accumulated capital to work. An essential component of this on-going thrust is a substantial effort by the mining industry to improve the performance of labour by providing most-productive work schedules.

Jan 1, 1996

Slime Flotation Using Ethoxylated Surfactants in Solutions of the Electrolytes

Sep 13, 2010

By R J. Holmes

An accurate knowledge of the chemical, mineralogical and physical characteristics of ores and mineral products that are mined, processed and traded is crucial to effective resource utilisation, plant design, process optimisation and finally quality control to ensure that contract specifications are met. However, all too often the responsibility for sampling is entrusted to managers and personnel who do not fully appreciate the significance and importance of collecting representative samples for analysis, and everyone seems satisfied as long as some material is collected and returned to the laboratory for analysis. Furthermore, sample stations incorporated into the design of new plants are often the first casualties when cost cutting exercises commence. This needs to change, because there is little point in accurately analysing samples if they are not representative in the first place. The resultant analyses can be next to meaningless and the effort taken to analyse such samples is to a large extent a waste of time and resources.Ultimately, a poor knowledge of the characteristics of ores and mineral products limits the ability of mining companies to optimise the life of ore resources and plant performance, and failure to meet final product specifications can have disastrous consequences, including price penalties and more seriously loss of sales contracts. It is high time that sampling is given the attention it deserves as the first critical step in the quality measurement chain.CITATION:Holmes, R J, 2013. The importance of sampling in the mineral industry, in Proceedings MetPlant 2013 , pp 34-49 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 15, 2013

Hindered settling devices (teeter bed, up-current) are widely used in the mining industry to classify mineral streams into various size fractions and to separate minerals. In the coal industry these devices are extremely successful in separating coal of low densities from shale and pyrite. In the beach sand and in the iron ore industry, this equipment is used to beneficiate minerals either as stand alone units or lately as classifiers in spiral circuits. The challenge that these applications give to metallurgists is to be able to simulate the equipment by using mathematical models with or without the aid of small bench scale tests. In any green fields and many brownfields projects, limited amounts of samples make pilot plant tests difficult. Although there are mathematical approaches available, the accuracy is of such a nature that it can not be used for design purposes. This refers to the use of StrokeÆs law, NewtonÆs and the so called intermediate law as is widely published. Research done by the author indicates that in most applications none of the above laws apply. Using the original data as published by Perry and Chilton (Chemical Engineering Handbook, pp 5-64, 1973) and re-plotting it indicates that the settling velocity of particles is a function of (particle diameter)n where n varies between 1.2 and 1.6 which is different from that predicted by the intermediate law that suggests that n = 1.18. Another way of describing the relationship between the drag force and the Reynolds number is done by iterating between settling velocity and the Reynolds number. This needs more computer time but the accuracy obtained from this does add value to simulations. A small but simple test is suggested to determine the settling velocity of particles to enable metallurgists to determine variations from the theoretical calculations to determine the influence of viscosity and particle shape.

Jan 1, 2008

By Scales PJ, Ralston J

Fine coal particles have been examined with respect to dustiness and its connection with various physical and chemical properties. It appears that a given coal will tend to be dusty ifthe moisture content is low and if the inert maceral content and overall rank are high. The hydrophobicity ofa coking coal (Young-Wallsend) and a steaming coal (Blair Athol) was examined in detail by a dynamic contact angle technique. The YoungWallsend coal had a higher contact angle, on average, than the Blair Athol sample. This result has important implications for dust suppression and associated processes.

Jan 1, 1986

The detailed work done by Stillwell and Edwards on the occurrence of cobaltite and safilorite-Iollingite at the South Mine, followed by its presentation as a paper to the Institute, calls for, a few notes on its occurrence elsewhere in the Broken Hill field. No massive cobaltite similar to that in the South Mine veinlet is known except from the Consols Mine (as mentioned in the paper). Fine grained cobaltite has, however, been found in low-grade ore from the North Mine. Microscopic grains occur in a mineralized green feldspar pegmatite. The feldspar has been replaced in part by graphite, and the cobaltite occurs in association with the graphite. In its hardness, pinkish-white colour, and resistance to the standard etchingqeagents it is similar to the South Mine cobaltite; it is etched by acid permanganate solution. An interesting feature of this occurrence is the way in- which some of the minerals (notably galena) have forced apart the graphite lamellae in crystallizing, forming lenses enclosed by the curved cleavage surlaces 0;[ the graphite.StillwelI and Edwards cite a note by G. Smitht for the statement that "cobaltite has been recorded from the Australian Broken Hill Consols Lode in the vicinity of the rich silver deposits, though not in contact with them."Smith, however, is here referring to the oxidized zone. Elsewhere in the same article he states "... a deposit of cobaltite in a very much altered condition was found. This was impregnated with silver, and assayed as high as 3,000 ounces," Of the cobaltite in the unoxidized zone, Smith simply states that it became rarer with depth.Cobaltite has also been recognized by Mr. H. F. Whitworth, M.SC., Curator of the Mining Museum, Sydney, in specimens from Burt's Copper Mine eight miles south of Broken Hill.

Jan 1, 1944

Triboelectric Charge and Separation Characteristics of Industrial Minerals The basic principles of triboelectric charge and separation of minerals and the factors affecting the entity of the charges developed on mineral surfaces are discussed and the surface pretreatment methods by which the electrophysical properties and thereby triboelectric charging and separation of minerals can be artificially altered/modified are reviewed. Furthermore, the triboelectricfication theory of materials is envisaged from the chemical concept of acid-base donor-acceptor and an attempt is made to correlate the physical concept of triboelectrification with the donor-acceptor properties. The triboelectric charge characteristics of the quartz, calcite and wollastonite mineral samples for different size classes were defined using different tribocharging medium. Based on the triboelectric charges acquired by mineral samples their energetic work function values are estimated. In addition, the main electrophysical properties, ie dielectric constant and electrical conductivity, of different size fractions of the mineral samples are measured and their donor-acceptor chemical properties were defined. A series of triboelectric separation tests were conducted to explore the possibilities for separation these mineral from each others. The results from the triboelectric charge and separation of the single mineral systems showed promising prospect in separating quartz, calcite, and wollastonite from each others. Finally, attempts were made to explore the possibilities to implement triboelectric charge and separation process to real ores. Promising results achieved when separation of calcite from silicate impurity was sought from a carbonate ore. A very high purity (99 per cent) calcite product was obtained at a recovery of 80 per cent. Interesting results were also achieved to concentrate wollastonite from a complex silicate ore containing quartz, different feldspars, wollastonite and other Mg-Fe silicates. In this case conditioning of the ore with salicylic acid at defined temperature and relative humidity was found to be essential to concentrate wollastonite. The outcomes indicate despite the fact that triboelectric charge and separation process has not been completely perceived, it pronounced to be an environmentally friendly and economically viable technique for minerals and wastes beneficiation. Being a dry beneficiation technique the process has special appeal, which must be explored further in particular for treating industrial minerals.

Sep 13, 2010

By H M. Parker, G Verly, T Postolski

Assessing the uncertainty and risk in mineral resource estimation is required for best practice and is implied by the public reporting codes in the categorisation of mineral resources and reserves. One industry best practice is quantifying the risk on future production for a given period, which can be done using two geostatistical approaches: conditional simulation and drill hole spacing studies based on estimation variances. Conditional simulation can provide a more complete and flexible answer to the problem, but it takes a fair amount of time to complete. Drill hole spacing studies are simpler, faster and can provide reasonable assessments of mineral resource uncertainty.This paper is a presentation of the principles, theory and practice of drill hole spacing studies. Various types of risk assessment are considered. Difficulties encountered in practice are discussed, and solutions are proposed. The important parameters impacting the results are reviewed. Examples of results and sensitivities are shown.CITATION:Verly, G, Postolski, T and Parker, H M, 2014. Assessing uncertainty with drill hole spacing studies – applications to mineral resources, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014, pp 109–118 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 24, 2014

The cost of production from truck and loader fleets is influenced by management development of the culture of the organisation, work practices, systems and procedures of the production and maintenance teams. Establishing if the cost of production is the best that can be achieved then requires the measurement of results against established standards of performance. This paper provides a series of discussion points of the factors that influence the cost of production from men and machines for large scale open pit mining operation and provides some suggested performance standards in the form of Benchmarks. Most of the references have been drawn from established large scale deep pit mines in USA, Canada and Australia which have had to implement and constantly fine tune cost efficiencies in order to survive. The discussion provides:ò a review of priorities or the relative importance of the various cost elements for a mining system;ò suggestions of systems and procedures for the operation and maintenance of machines which are considered to yield the best overall results;ò examples of operations that have developed and implemented management systems and controls that are achieving good results in specific functions; andò suggested benchmarks of performance.

Jan 1, 1992

IT has often been stated in the past that the materials known as inert fillers were merely adulterants nsed in the manufacture of paint, and that their purpose was to cheapen paints made from more expensive pigments, such as zinc oxide or white lead. In recent years, however, practical tests in various parts of the world have proved that many of the inert fillers, when used with wisdom, possess very definite and advantageous properties.Another oft-repeated statement which had a far-reaching effect in the past, and which is not without influence to-day, is that the very best paint must always be made from a pure pigment, without admixture with either a fellow pigment or an inert filler. Both or either of these statements may be true in a few isolated instances, but for the vast majority of ordinary painting conditions there is an abundance of experimental evidence to prove that neither is true.With the desire to further investigate these points and po 'determine the best combination of pigments and fillers for use as an outside white paint on plant buildings, a number of panels were prepared in the laboratory of this company.

Jan 1, 1924

The corrosion of aluminosilicate refractories by soda from three different sources has been studied by microscopic methods. Sodium sulphate from oil ash, sodium chloride used in glazing structural clay products, and sodium borate from borax-impregnated wood ash have fundamentally the same effect on the refractories. The soda is the chief medium of reaction and fluxing, the sulphur, chlorine, and boron being volatized as sulphuric, hydrochloric, and boric acids.INTRODUCTIONBecause of their strong fluxing action, alkalis are one of the main causes of corrosion and slagging of refractories.The action of potash and soda on refractories follows somewhat similar lines, although it is common for one alkali to be greatly in excess of the other. The course of the reaction in a number of cases of alkali attack has been studied by microscopic and chemical methods. For example, the action of potash on blast furnace refractories was studied by Kraner (1942) and Rigby and Richardson (1947), who described the occurrence of various potassium aluminium silicates. Its action on cement kiln refractories was described by Brisbane, Segnit, and Weymouth (1957). The action of soda on glass tank refractories has been studied by many people, for example Bisby (1956) and Resch (1954). Clews, Hugill, and Green (1940) made a microscopic examination of the attack by soda on silica bricks from a gas retort.Some recent cases of corrosion of aluminosilicate refractories which were brought to the attention of the Division of Building Research, C.S.I.R.O., illustrate phenomena which occur under conditions different from those...

Jan 1, 1964