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IN all wet concentration processes it is of primary importance to determine to what degree the crushing must be carried in order to obtain the maximum profit per ton of ore milled.To effect a clean separation, either by gravity or flotation treatment, between either one valuable sulphide from another, or a sUlphide from the gangue, the ore must have been subjected to grinding to such an extent that the particles to be separated are completely liberated from each other.Insufficient crushing will result in either an incomplete separation of the sulphides from each other, and thus a loss of the one sulphide in the other, or else a loss of the valuable sulphide in the gangue.This being so, the question arises whether the added cost of extra crushing would be economically warranted by the increased recovery consequent on such a step.

Jan 1, 1927

By B A. Tapp

The minerals industry in Australia is currently regarded as the country's economic saviour; the bastion of economic security. As Fitzgerald (1974) stated, 'Australia's natural endowments in minerals are the envy of most countries of the world'. As a result the proposed new mineral developments are on a scale that hitherto in the sixties would have been completely un-envisaged. It is reported that Australia is poised on the verge of a 16 billion dollar mining-based investment boom: a boom that will see Australia dominate the energy export field, the mineral processing field, and create the 'coal dollar'. This growth scenario has many inherent dangers, and it is the authors' contention that these should be carefully considered before further development proceeds. Two of the major problems related to the mineral industry growth scenario are the predictability of the future metal market, and the energy cost of mining. The latter problem is the one discussed here. The mining-mineral processing industries in Australia currently use about 36 per cent of Australia's primary energy budget. This large energy input is dominated by two major industries, iron and steel and the rapidly developing a1uminium industry. These two combined use over 20 per cent of the total Australian energy budget. In an industry which is export oriented about 96 per cent as expressed in ex-mine value terms û much of the energy input is exported along with the product. The authors therefore urge that serious consideration by the mineral industry be given to the relatively high energy intensiveness of process operations, especially in respect of the aluminium industry.

Jan 1, 1980

The physical setting and background to mining operations on Misima Island and the overall plant lay-out are outlined. Developments and changes made to each section of the plant are described as they were encountered during commissioning and initial operation.

Jan 1, 1991

By J D. St George

Flyrock is the unexpected and undesirable projection of rock fragments during detonation of a blast and managing this risk is becoming an increasing challenge as urban development encroach toward mineral extraction sites. The basic factors associated with flyrock are discussed in relation to geology, blast design and management. Published data of historical flyrock events are investigated and compared with local information on incidents. Good agreement was found between the data sets. A computer program of flyrock was developed using projectile motion based on launch velocity and angle, rock size, shape and density. This deterministic model was coupled with a probability model to simulate blast events. The impulse time ?t of the explosive pressure was taken as the stochastic variable to replace launch velocity. The variables were calibrated to replicate field data. A simulation was executed to demonstrate the capability of the approach to defining flyrock danger zones. For a simplistic situation it was identified that an appropriate distance to be cordoned off for the blast danger zone is a radius of 120 m in front of the blast and 65 m behind.

Jan 1, 2001

The main orebody of the Bodangora mine is a metalliferous quartz reef within a major fault plane in the strongly folded and faulted volcanic rocks of the Ordovician-Silurian Oakdale Formation. The similarity of the type of mineralization to that of other pyrometasomatic deposits in this area suggests that the mineralizing fluids originated in the nearby Wuuluman Granite.The associated Mitchell's Creek West or Dick's reef is discussed briefly.

Jan 1, 1970

By A Kindred

The Bogong Hydropower Development is a 140 MW high head power project currently under construction in Northern Victoria. The project is the final link in the Kiewa hydroelectricity scheme, which was originally constructed in the 1950s. Due to its location in the Alpine National Park, the waterway for the Bogong project must be located entirely underground. A series of shafts and tunnels is being constructed to transfer the water from the headworks at McKay Creek to the new power station located on the shores of Lake Guy in Bogong village. The difference in elevation between the headworks and the power station is greater than 420 m, which poses particular issues for the design and construction of the waterway. The purpose of this paper is to describe the design and construction planning aspects of the tunnelling and shaft excavation and lining works for the waterway. The tunnelling works includes 5.7 km of hard rock tunnel boring machine (TBM) driven tunnel, 1.1 km of drill and blast tunnel and two deep shafts. The tunnels and shafts are lined with a mixture of permanent rock bolts and shotcrete, concrete lining and steel lining. The viability of the Bogong Hydropower Development relies heavily on the ability of the TBM to excavate at high speed through the East Kiewa Grandiorites. Particular attention was given during the construction planning stage to understanding the excavation characteristics of this material, and designing a suitable hard rock TBM that would be capable of meeting the program requirements of the project.

Jan 1, 2008

In sizing of wet coal by the horizontal vibrating screen, screen openings to be used is much restricted, because coal is sticky and its bulk density is little. The electrically heated screen and other various types of screen had been tried to screen raw coal and coal as raw materials at a few mm. However, they failed to realize satisfactory results. On the other hand, fine sizing of coal is requested by many fields. For example, raw coal is desired to be screened at the fine rate, before being fed to the coal preparation control system in order to transport undersizes as unprepared coal particles and to reduce load in coal preparation waste water treatment system.1) Coals fed to the fluidized bed boiler also should be sized at a few mm. Regardless of many requests on fine sizing of coal, it seems that there are many cases to omit the basic screening process, because the screening is very difficult on a industrial scale. Size control as pretreatment of coal as raw materials is presented as one of the basic screening processes. In 1979, Kinki Industrial Co., Ltd. and Nippon Steel Corporation jointly succeeded in developing the vertical centrifugal screen. Closed -circuit crushing system by the use of this screen has operated actually at N.S.C, Hirbhata .Works, and realized the anticipated result. Consequently, this system has established the position as the most basic technology in the coal preparation. 2), 3), 4) This system has been also introduced to Nakayama Steel Works, Ltd. in 1982. This system termed the CPC (Coal Preparation Control) Process has been operated smoothly in both N.S.C. and Nakayama. Reported herein is the practical application of the vertical centrifugal screen termed V3-Separator. (V3 means vertical, versatile and vibration.)

Jan 1, 1984

By F Mavroudis, M Gaastra

Due to the increasing demand for resources worldwide, efficient utilisation of raw material deposits and recycling technologies become more and more important. Growing industrial nations and increased living standards require a large raw material supply. Hereby responsible handling of existent primary and secondary raw materials is indispensable. By utilising state-of-the-art technologies resources are extracted, recovered and recycled more efficiently which increases sustainability. Hereby sensor technologies combined with intelligent data processing systems in particular provide a considerable research area. Innovative sensor technologies are already implemented during recognition of material-specific characteristics, during elemental recognition as well as during machine control. They are applied to attain increased automation levels of mining machineries, higher recoveries during mining and processing as well as higher recoveries. To be able to face the increased demand for sensor technologies and the integration into raw material industries, an interdisciplinary association of three RWTH Aachen University Institutes has been founded. The association has expertise on increasing productivity and capacity utilisations by automating mining and recovering processes by sensor technologies. Due to the utilisation of sensor systems, materials and structures can now be detected and elementary analysed on a real-time scale. The developed and enhanced techniques are the key for any ambition of autonomous plants and machineries. This paper gives an overview on the regarded sensor technologies for material recognition, machine automation and mineral processing. The authors present concepts based on extensive laboratory and field studies of successful implementation and application the technologies considering special mining conditions. Overall three applications are described to demonstrate the potential of sensor technologies for autonomous and sustainable mining: real-time analysis: recognition of elementary compounds during extraction processes; multi-sensor system EiControlPlus: designed for automation of longwall shearers by complete detection of the machineÆs environment; and sensor-based sorting: applied in recycling and mineralÆs industries.

Sep 26, 2011

The provision of electrical power is an important consideration in project develop- ment. The first step to be taken in this area is to assess the power requirements of the project. The alternatives of taking a supply from a power authority or providing local generation can then be considered. This requires additional definition of the prob- able characteristics of the supply. The availability of authority power in Australia is limited by the extent of the state power grids. Recent developments now allow these grids to be extended and their load capacity increased to meet major load increases at less cost than was possible pre- viously. The options for local generation include diesel, gas turbine, steam, hydro, solar and wind, each having its particular performance characteristics and costs. The choice of fuel for diesel, gas turbine, and steam plant likewise involves consideration of a range of factors. The arrangements adopted for a number of development projects illustrate some of the aspects which influence the decisions on power supply.

Jan 1, 1986

The CSIRO acid alumina employs the essential steps of digestion, hydrolysis and calcination to produce pure alumina from ores too high in silica or too low in grade for the Bayer process. The two latter stages have been described in some detail previously but the digestion stage requires separate dis-cussion since ores vary widely in composition and reactivity. Kaolinitic clays require. roasting to 8000C to render the alumina soluble in the 11 per cent sulphuric acid used in the process while some ferruginous laterites require roasting to reduce the reactivity of iron minerals. The iron content of pregnant solutions is kept at a low figure by digesting at temperatures where the solubilities of ferric oxide or basic ferric sulphates are small. A.two-stage, counter-current digestion is necessary to extract a high percentage of alumina from the ores and to pro-duce a basic pregnant liquor, with an S03:Al203 ratio of 1. 9 suitable for high temperature hydrolysis. The second stage of digestion, called the modification stage, treats slightly acid liquors with exces's of ore in the temperature range 1200- 1400C. The first stage operates at 1700-190 C to extract further alumina from modification residues, using recycled acid obtained from later steps of the process. Both temperature ranges are critical for economic operation and for proper con-trol of the iron content of solutions. In batch experiments, thirty minutes is regarded as a suitable retention time for digestion and modification; ores which require much longer than this are less suitable for the process. Impurities. such assilica, titanium and vanadium oxides are discarded in the residue along with iron oxide and do not contaminate the final product. Bivalent metallic sulphates such as MgSO4 can build up in the circuit to a very considerable degree without affecting. product purity.Comparison with other processes shows that the C. S. I. R. O. process is superior for control of contamination by iron, which is the major problem in acid processes. The pure intermediate product (3 A1203. 4 S03. 9 H2O) is also more convenient for cal-cination to alumina than the hydrated aluminium sulphate usually recovered in other processes. Detailed cost comparisons must await pilot-plant evaluation of the C. S. I. R. O. process.

Jan 1, 1963

By Met M. E

In choosing the subject for my address to you this evening I was actuated by the knowledge that in the past Australian metallurgical problems have been solved by the introduction of extremely interesting processes. Frequently such processes originated in this country, or at least were first adopted here on a large scale.Chronologically there comes to mind the application of chlorination to the Mount Morgan ores from 1888 onwards.Then the application of pyritic smelting to the Mount Lyell ore body in 1896, followed closely by the successful flotation of zinc blendÇ! at Broken Hill, about 1900, and the treatment of the refractory Kalgoorlie gold ores by roasting and cyaniding. With the development of the differential flotation process at Broken Hill came the production of a slime lead concentrate carrying zinc which necessitated the use of a high zinc slag in the lead smelting process. Although previously considered impossible, the necessarytechnique was successfully evolved at Port Pirie resulting in the accumulation of large tonnages of zinc-bearing slag as potential sources of that metal. The past twenty years have witnessed:-(a) The establishment of a flourishing iron and steel industry, with its attendant coking and by-product plant at two centres in New South Wales, namely, Newcastle and Port Kembla.(b) The establishment of an electrolytic zinc process at Risdon in Tasmania.*Presidential Address, Melbourne, 20th August, 1936.

Jan 1, 1936

By Jancar T, de Guzman M M, Matthews B, Tu J. Y

The use of computational simulation to predict the performance of existing equipment or for the design of improved mineral processing equipment will be referred to as Computational Mineral Processing (CMP) in this paper. The emphasis will be on solving the governing equations for liquid solid flows in complex geometric domains to obtain, typically, the three-dimensional distributions of velocity and pressure for the liquid phase and the velocity and concentration for the solid phase. The underlying technology, computational fluid dynamics (CFD), is very well-developed in other industries (aircraft, car and chemical) and forms a vital part of product design and analysis. The subsequent design of improved mineral processing equipment may also involve finite element structural analysis (FESA). Computational fluid dynamics (CFD) and finite element structural analysis (FESA) are part of the generic discipline of Computational Engineering and Science (CES). Ciment and Scherlis (1993) define CES as `The systematic application of computing systems and computational solution techniques to mathematical models formulated to describe and simulate phenomena of scientific and engineering interest'. Increasing computer power (Kaufmann and Smarr, 1993), is a dominant factor determining the rapid growth of industrial utilisation of CES. This increase is happening at both the supercomputer and the workstation level. Indeed, today's typical workstation, a Hewlett-Packard 735, is as powerful as a CDC 7600, the leading supercomputer in 1970. Future computer architectures are expected to become increasingly parallel (Gartner Group, 1990) allowing a sustained performance of a teraflop (a million megaflops) to be achieved well before the Sydney Olympics in the year 2000. It is recognised that the modem development of most disciplines in the physical sciences rests on the three complementary strategies of experimentation, analysis and computational simulation. As the 21st century is approached the volume of computational simulation, both fundamental and applied, is growing dramatically and the role of experimentation is diminishing. In the area of equipment design, CES provides the following advantages over experimental testing and measurement: 1. lead time in design and development is significantly reduced; 2. CES can simulate conditions not reproducible in experimental tests; 3. CES provides detailed and comprehensive information; and 4. CES is more cost-effective and time-efficient. The ultimate benefit for industry is greater productivity and hence greater profitability. The broader issues in relation to CFD are discussed by Fletcher (1993b). In the five- to ten-year time frame, growth in computer power will make it practical to combine CFD and FESA with optimisation procedures to produce a design process that is almost fully computerised. It is expected that fully automatic

Jan 1, 1995

Techniques Used and Problems Encountered in Normal and Reverse Circulation Drilling at the Mt Roseby Project, Cloncurry, North West Queensland

Sep 13, 2010

Suggestions have been made at various times that there may be a recurrence of lodes similar to those at Kalgoorlie in the country to the south of the Golden Mile, but, so far as is known, there has been no geological evidence to support these suggestions apart from the possible extension of the younger quartz-dolerite greenstone in this direction.Geological mapping carried out by the writer in the Coolgardie district in 1946, provided some additional geological evidence to support this claim, and the ideas then held have since been expanded and are now considered to be sufficiently advanced to present them as concrete suggestions. As will be seen from the following pages, the critical area for lode prospecting is Hannan's Lake, where the basement rocks may include younger quartz dolerite greenstone, which, although perhaps distributed over a smaller area than at Kalgoorlie, could, on structural grounds, have a similar fracture system and similar ore deposition.There is little need to stress the importance discoveries in this area would have in prolonging the life of the field, and stimulating the post-war gold mining revival.Previous Work: Only the publications having a direct bearing on the preparation of this paper are given in the list of selected references, but the writer is very conscious of the fact that much other geological work has been carried out in the Kalgoorlie district since its discovery, by the W.A. Department of Mines, by mining companies, and others, all of which has contributed to the present knowledge of the field, and acknowledgment of the value of this work is given herewith. In presenting the suggestions in this paper a broad structural control of ore deposition is assumed, but this has already been established in other parts of the goldfields of Western Australia, including adjacent areas. In the early nineteen thirties, the Western Mining Corporation commenced work on the basis that there was a close relationship between geological structure and auriferous ore deposition, and a similar approach was first made by the Geological Survey of Western Australia in the South Yilgarn in 1935. These ideas were further developed during later surveys, particularly in the North Yilgarn and the Mount Margaret Goldfield.During the Coolgardie Survey in 1946, broad structural mapping was done in greater detail than before, and the structural ideas were implemented and further developed, leading to some success.Other work to which particular acknowledgment is given is that of Stiltwell, Gustafson and Miller, Forman, Prider and Finucane, at Kalgoorlie, and that of Honman in the Kalgoorlie-Coolgardie district, references to which are given at the end of this paper.Valuable constructive criticism of this paper has been given by Professor E. de C. Clarke and Dr. R. T. Prider, of the University of Western Australia.

Jan 1, 1950

It is proposed to deal with those raw materials which are produced in South Australia to meet the needs of the country's steel industry. They are chiefly, iron ore, limestone and quartz.Iron ore and limestone are fed to the blast furnaces of Newcastle and Port Kembla together with coke to produce the hot metal charge for the open hearth steel furnaces.They are also qsed in the raw state in the steel furnaces to assist in the conversion of the hot metal to steel. The iron ore is quarried from' Iron Knob and shipped from Whyalla to Newcastle and Port Kembla, whilst the limestone is supplied from the deposits at Rapid Bay and shipped in the same manner.Quartz is used in the manufacture of ferro-silicon, an alloy which is added to the ladles of molten metal tapped from the open hearth furnace in the case of almost every grade of steel. It is obtained from a quarry situated between Iron Knob and Whyalla, and shipped to Newcastle.IRON OREWith the exception of several small quarries situated at Breadalbane, Cadia, Cowra, Crookwell, Michelago, Jerrawa and lerraama in New South Wales, the iron ore requirements of Australia's steel industry to date have been met from Iron Knob and the Middleback Range in South Australia.Several of the small deposits in New South Wales were worked during the war years of 1941-44 during the shipping emergency and produced 1,355,417 tons, compared with an output of approximately 43,000,000 tons from Iron Knob between 1901 and 1949.

Jan 1, 1951

THE Australian States and New Zealand have for many years provided instruction in mining, metallurgy, geology, and their allied subjects through their Universities and Schools of Mines. Though such education has been provided at considerable expenditure, there is no legal recognition whatever given to the holders of degrees, diplomas, or certificates granted by the authorities controlling these educational institutions. Certain of the, Australian States and New Zealand require, however, that mine managers and other officials employed by the mining industry shall 'hold' certificates granted by their respective Mines Departments.The position at present is that each educational institution is practically a law unto itself, and therefore in many ways there is a want of uniformity amongst institutions all aiming at the same result the training of mining men. The object of this paper is, in the first place, to point out certain aspects of this want of uniformity, and thereby how disabilities accrue. Some points in connection with the granting of State certificates will also be...

Jan 1, 1915

By X B. Sun

Mining work is a high-risk operatation under a special environment. It is affected by space, lighting, noise, vibration, dust, air pollution, etc as well as coal seam conditions, complicated geology construction, combustion of coal, gas, coal dust, etc. Factors which affects safety production are numerous, eg natural conditions, technical equipment level, producersÆ and managersÆ qualities. It is a complex system engineering to ensure mining safety and high efficiency. Among the ideology, methods and measures of safety management are the most important factors besides safety technology. Mine productive environment is a main problem that affects minerÆs work as far as safety and health are concerned. Combining ChinaÆs mine productive environment situation and using human ergonomics theory, this paper explores a series of measures and suggestions as to how to reinforce safety management, how to build up the safety management ideology, how to improve the mine production environment, how to decrease coal mine accidents, and how to ensure mining safety and high efficiency.

Jan 1, 2003

By E Kunz

Decreasing the gas content in the worked seam by degassing before the start of winning has proven its worth in some areas of German hard coal mines. On the one hand, it removes the risk of gas/coal outbursts and on the other hand it reduces the gas inflow into the longwall. The underground experiences of the last 30 years have led to a æhit listÆ of coal seams with respect to their suitability to predegassing. Trials in the DMT laboratory and also results gained in the deposit show that the suitability of a seam for predegassing depends on its rank. In seams with volatile matter of 20 - 30 per cent, high efficiency ratings are achieved as a rule, with lower ratings both in seams with lower and with higher content of volatile matter.If the rock pressure is unusually high, the efficiency rating of the predegassing is lower, even in seams which would normally be suitable for this process. Under unfavourable conditions, for example below or above residual pillars, in-seam boreholes cannot be drilled successfully and the method is not practical. But if the worked seam was already stress relieved, the predegassing has an optimal efficiency. Latest investigations show that the distance between the in-seam boreholes can be extended. But in that case, the time necessary to reach the same reduction of the gas content increases considerably.

Jan 1, 2005

The title of my address today 'An Environment for Mineral Development' is a play on words, but I wish to use the meaning of the word environment in the broadest possible context to comment on those factors that control mineral development in New Zealand today. Of prime importance, let us consider the current economic environment in which New Zealanders live and work, as individuals and communities, and as a trading nation. It is the expanding growth requirements of the emerging nations and the interactive economic forces of our international trading partners and competitors, that dictates New Zealand's economic environment and thus the priority to develop its natural resources. As an itinerant New Zealander who has kept a watching brief over the economic environment in New Zealand over the last 30 years, I say, without prejudice, that I am concerned to have seen New Zealand's external and internal trading position deteriorate so rapidly in the last decade. I am concerned that a significant proportion of the population has been extremely slow to realize that with the creation of the European Economic Community, in the late 1950s, and following the first OPEC oil crisis in 1973, New Zealand in a corporate sense came close to technical bankruptcy.

Jan 1, 1985

The paper explains the genesis of the Ballarat College of Advanced Education to its unique position in mining engineering education. A description follows of the development of the Graduate Diploma in Occupational Hazard Management which commenced in 1979 in the cooperative mode of four groups of three weeks full- time study followed by twenty-three weeks in industry. In particular an analysis will be given of the state of origin of students, ages and employing industries. Given the experience from the evolution of this course a similar process is described for the Graduate Diploma in Mining which has been accredited to commence early in 1987.

Jan 1, 1986