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Mining education has received almost continuous discussion since its inception and most people engaged in the mining industry and in mining education feel at some time the urge and necessity to express their views. This paper is not a comprehensive survey of past and present practices and accepted principles, but a personal opinion of the form mining education should take at university level. It is expressed because of a dissatisfaction with the existing courses offered to students. It is hoped to provoke discussionand bring forth guidance to those engaged in mining education. After all, students spend four or five years at a university and it is desirable that the graduate should be something more than just those many years older at the end of his course.POST GRADUATE EMPLOYMENTThe first problem confronting the university should, be to discover what the mining industry wants and expects or graduates. This must influence the university course and yet universities have done little to seek this information, and if suggestions have been offered by industry; universities appear to have made little use of them. University mining curricula are basically what they were 50, 100 and even 200 years ago. (See Appendix.) Whether this reflects the unchanging problems of mining the wisdom of early professors, the conservatism of subsequent professors or inability to apprectate necessity for changes, is debatable.Unfortunately there is no uniformity in the type of employment offered to new graduates: Some mining...

Jan 1, 1959

By J L. Lett, I Brunton, T Thornhill

Block cave fragmentation has been documented in the literature to have a significant impact on mine design, performance and downstream material handling and comminution processes. Due to this impact, emphasis is placed on the premining prediction and subsequent quantification of primary and secondary fragmentation distribution. This paper discusses the fragmentation prediction and assessment methodology employed at the Ridgeway Deeps (RWD) and Cadia East PC1 (CEPC1) cave operations.Prediction of drawpoint fragmentation was based on an iterative process, which relied on an improved quantitative and qualitative understanding of the rock mass as the mining project developed. In particular, the collection of scanline mapping data provided detailed information in relation to discontinuity trace length, persistence, termination characteristics and large-scale planarity. This allowed an improved estimation of select modelling input parameters, in particular ‘block forming’ discontinuity orientation and strength characteristics.With the start of production, drawpoint fragmentation assessment was undertaken using digital image processing (DIP) techniques for drawpoint extracted tonnes up to 61 000 t. This technique provided a consistent methodology to estimate changes in fragmentation as the block cave matured. It can generally be concluded that the measured mean fragmentation distribution became finer as drawpoint tonnage increased. The incremental change in fragmentation distribution (per 10 000 t) was not uniform, with step changes evident. In addition, for a given geotechnical domain and drawpoint tonnage, the measured fragmentation distribution range was found to vary significantly. A possible explanation for these observations may relate to the disturbed flow behaviour noted from marker experiments at RWD and CEPC1. These experiments indicate that material reporting at the drawpoints (for any given tonnage extracted) may be sourced from highly variable heights within the cave, with finer material preferentially reporting.A comparison between predicted and measured drawpoint fragmentation distribution indicated two general findingsa close match between predicted and measured distributions for material greater than 1.0 m3an under prediction of finer material passing 0.5 m3 relative to measured.The findings would indicate that the fragmentation modelling frameworks utilised at both RWD and CEPC1 were deficient at predicting the percentage of finer material for both primary and secondary fragmentation.The wide range in fragmentation distributions observed in the measured results, and the discrepancy between modelled and measured fines should be considered in the design of mine (material flow, extraction level geometry and draw rate), material handling (crushing and material movement), and downstream milling (comminution and metal recovery) processes for future block cave mines at the Cadia Valley Operations (CVO). With respect to fragmentation distribution range, a sensitivity analysis should be undertaken for these design considerations, with a range in predicted fragmentation distributions investigated (for example, lower quartile, mean and upper quartile). For future mines with similar geotechnical and mining conditions, the calibration of fines should be considered in any fragmentation distribution prediction to match those measured previously.CITATION:Brunton, I, Lett, J L and Thornhill, T, 2016. Fragmentation prediction and assessment at the Ridgeway Deeps and Cadia East cave operations, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 151–160 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

Air tabling of zircon-rich non-conductor products containing quartz enables most of the fine quartz present to be rejected without a markedloss of zircon. The coarser quartz in the air table feed can be separated from the zircon by screening one or more air table products, the oversize products containing most of the quartz and little of the zircon. Air tabling, with or without screening, is more efficient than wet tabling alone for the removal of fine quartz, but not for the removal of coarse quartz. Practically all of the quartz can be separated from the zircon by using wet tabling in conjunction with hydraulic classification, or by using air tabling in conjunction with dry launder treatment, in which a degree of sizing takes place that is advantageous for subsequent air tabling.INTRODUCTIONBack-dune and inland beach sand deposits usually contain fine wind-blown quartz, and neither spiral nor wet table concentration, alone or in conjunction, makes a clean separation of heavy minerals from quartz. Many rutile plants recover rutile and zircon from a low-quartz, wet-table concentrates by means of magnetic and electrostatic separation; some rutile and zircon are lost in the table tailings. Other rutile plants, and two of the ilmenite plants in Western Australia, recover rutile or ilmenite respectively, from a spiral concentrate containing several per cent of quartz, and then subject the non-conductor product to an additionalgravity concentration process to separate the zircon from the quartz. Some zircon is lost in the additional gravity process, but all of the rutile or ilmenite in the spiral concentrate is, or should be, recovered as high-grade concentrate. The higher recovery of rutile or ilmenite by this treatment method is offset by the expense of drying part of the feed twice, as a wet process is usually used to separate the quartz...

Jan 1, 1962

By Madgwick J. C

A novel, microaerobic, heterotrophic microbial leaching system for manganese dioxide is described. Mixed natural microflora were enriched by addition of sugars and crude plant nutrItIOnal supplements. Between 84 and 104 mg MnH was solubilized per gram sugar at I per cent (w/v) concentrations for fructose and galactose in the presence of 0.03 per cent w/v dried microalgae (a Chlamydomonas species). Some 42 per cent soluble manganese was dissolved by microbial action on MnO, (3 per cent (w/v) pulp density) using a 10 per cent (w/v) molasses growth substrate.

Jan 1, 1983

G. R. Compton (Gold Mines of Kalgoorlie (Australia) Ltd., Fimiston, W. A.) : In congratulating Mr. Hooker upon his resume of Mr Parry's paper I have in mind the fact that he carried out the research into pipe pressures. Hydraulic filling as practised in Kalgoorlie has created world wide interest, with these pressures and percolation being vital points.Early in the 1950s, representatives of the Kolar field were conduGted over the local mines where stopes at depths below 2,000 ft were being filled. The problems of pipe pressures were their main consideration since depths of up to 10,000 ft were envisaged.Mr Krishnaiah and Mr Murthy from the same field are with us today and perhaps we may hear of their experiences with depths of 6,000 ft and long lateral lines.J. Holly (Lake View and Star Ltd., Fimiston, W.A.): There is one phase, which I would like to mention myself, that has been very evident in Kalgoorlie operations. That is, we do not get the percolation properties that are obtained on many other fields in the world, and our tendency here has been to assess the quality of our fill more by its settling rate, i.e. the rate at which we can draw off clear water at the surface of the filling levels, rather than the rate that this water percolates down through the fill before it consolidates.We are tending now to measure the quality of our fill as a settling rate rather than as a percolation rate.Americans talk about percolation rates being the important property: If anyone has any experience on operating with fills with different percolation rates, I think their views would be very interesting to the meeting art this stage. Mr ...

Jan 1, 1965

By Kumar A, Mishra N. C

For each tonne of chromite ore mined in Sukinda, approximately ten tonnes of fine overburden material is generated. The overburden typically contains about 30 - 60 per cent Fe2O3, 0.3 - 1.1 per cent Ni, four to nine per cent Cr2O3 and 0.04 - 0.2 per cent cobalt and is being discarded leading to loss of valuable metals and creating environmental pollution. In order to take the advantage of presence of iron, nickel and chromium, the present studies advocate the utilisation of nickel lateritic chromite overburden for production of Ni bearing pig iron through blast furnace extracting maximum iron and nickel from the chromite overburden. The present paper deals mainly with the beneficiation of chromite overburden, sintering characteristics and thermodynamic studies. The beneficiation study shows that a beneficiated concentrate having Fe - 50 per cent and Ni -- 1.1 per cent can be achieved from chromite overburden having Fe - 30 per cent and Ni -- 0.7 per cent. Sintering studies have been carried out with bed height of 300 and 450 mm at a suction of 600 and 900 WG respectively. The results reveal that good quality sinter can be produced from chromite overburden concentrate with a basicity of about 1.0 and coke breeze consumption rate about 16 per cent. In all the experiments, Tumbler Index, Abrasion Index and Shatter Index was found to be in the range of 65 - 70, 4.5 - 5.5 and 85 - 90 respectively. The other parameters namely softening temperature, melt down temperature, reduction degradation test and relative reducibility have also been determined. A thermodynamic analysis has also been carried out to make a technological assessment of the process for the production of alloyed pig iron from chromite overburden in blast furnace which shows that it is possible to produce nickel bearing pig iron in blast furnace using the sinter up to 80 per cent. Techno-economic analysis reveals that this route will yield a substantial profit even after accounting for cost of beneficiation, extra coke, raw materials and extra slag produced.

Jan 1, 1999

By J Addai-Mensah, M Adam, W Skinner, J Begelhole, K Quast

Granulation of iron ore fines into robust granules is critical to successful sintering and blast furnace operations in iron and steelmaking. Iron and steelmakers desire iron ore granules with high strength, uniform size distribution and low fuel consumption to enhance efficient sintering operation. Unlike hematite ore, magnetite concentrates do not granulate easily at low binder dosage to yield coarser granules due to the absence of nucleus particles. This motivates the present study to harness the complementary properties of hematite ore to enhance granulation of magnetite concentrates via blending. The current state-of-the-art in hematite and magnetite blend granulation is reviewed, along with granule property limitations. Preliminary experimental work on granulation of hematite and magnetite blends as a precursor to sintering is reported.CITATION:Adam, M, Addai-Mensah, J, Begelhole, J, Quast, K and Skinner, W, 2017. Enhancing magnetite concentrate granulation by blending with hematite ore, in Proceedings Iron Ore 2017, pp 17–24 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

In the extraction of level bridge pillars in the South Mine by square-setting methods the general practice is to work transversely from the hanging wall in narrow sections three or four sets wide to the depth of the bridge-usually three sets. When the working block attains an area of twelve square sets, sand filling is run in, either by pneumatic (Proceedings No. 123, 1941) or hydraulic methods, in order to control the settlement of the general area and prevent the development of undue weight in the stope. Upon completion of the filling operations, or coincident with them, ore breaking is resumed and the transverse section of the bridge pillar gradually reduced. A number of these parallel sections may be working at the same time.In preparing a block of sets for filling a great deal of paddocking is required, both to contain the filling and to preserve access to ladderways and ore chutes which may be situated at some horizontal distance. Stope paddocking until recently was constructed of 10 in. x 2 in. boards nailed...

Jan 1, 1942

By Madgwick J. C

Microaerobic biodegradation oflow-grade manganese dioxide slurry tailings was demonstrated in enrichment cultures treated with dilute molasses at 30°C and pH 5·8. Supplementary nitrogenous nutrients, yeast extract addition and pH adjustment were not required.Continuously stirred, air-limited reactors were superior to still intermittently agitated cultures, in that, at 5 per cent (w/v) MnOz tailings and 5 per cent (w/v) molasses, the yield of 0.12 g Mn++/g molasses, the rate ofleaching of 1·06 g Mn++/l/d and a recovery of Mn++ of 58 percent from MnOz were 2·8 times, 1·7 times and 1·9 times greater, respectively. The best compromise in yield (0·45 g Mn++/g molasses) and rate ofdissolution (0·73 gMn++/l/d) was at 1 per cent (w/v) molasses in a stirred reactor.Where leaching organisms were separated from sterile ore by a bacteria impermeable membrane leaching was shown to be some 20 per cent due to diffusible metabolites and 80 per cent due to a direct contact between the bacteria and the ore particle's surfaces.

Jan 1, 1986

Radioisotope x-ray methods for the on-stream determination of copper, lead, and zinc in mineral product slurries were developed, and were successfully tested at the plant of Cobar Mines Pty. Ltd.The tests were made in three stages. Measurements to determine the precision of analysis were made initially on briquettes of the mineral products. The effect of slurry solids content variations was then determined by measurements on the mineral products in a recirculating slurry loop. The radioisotope analyser was finally tested in a series of on-stream measurements in the plant.Copper, lead, and zinc in flotation feed and in copper concentrate were determined to a precision ranging between 1·4 and 15 per cent of the mean element concentration in the slurry solids. These precisions are within limits required for plant control purposes at Cobar.

Jan 1, 1971

Factors of importance in the ntilization of coal fines are mentioned, and the results of flotation tests on coal fines from three important coal seams in New South Wales are presented.INTRODUCTIONEconomic utilization of fine coal is an important problem in the Australian coal industry, particularly as the proportion of fines mined is increasing with progressive mechanization.While the use of uncleaned coal fines may be economic, it may be preferable to beneficiate them, but the most economic process must be selected.For beneficiating coal finer than about 28 mesh, froth flotation can be applied, but mining engineers should avoid practices that may be detrimental to flotation. Such practices include the indiscriminate use of water, particularly that containing a wetting' agent, for dust suppression. In addition, clay stemming in wet conditions may produce slimes which could adsorb on coal surfaces, while the use of oils and greases as well as the application of stone dust and chlorides in roadway consolidation may influence adversely fine coal beneficiation.This paper deals with the application of flotation to samples of fine coal from the Bulli, Greta, and Victoria Tunnel seams. In addition a discussion is given of the mineralogical constitution, size analysis, and degree of liberation of ash constituents of the various samples.COAL SAMPLESRepresentative samples of coal from the Bulli, Greta, and Victoria Tunnel seams were obtained for testing.

Jan 1, 1961

THE art of mine surveying has made very great progress in recent years, and is still advancing, perhaps faster than any other branch of surveying. The scope of the mine surveyor's duties has greatly increased, his instruments and methods have improved, the responsibility of his position is greater, and the end is not yet in sight.It might be supposed that such a steadily growing subject would have an adequate literature, but this is by no means the case and outsiders commonly judge mine surveyors by their text-books. Hardly any condemnation can be too strong for most of these books. The English books truckle to the antiquated and crude methods apparently still in use in England, and thereby largely aid in perpetuating them; they commonly in illustrative examples give the distances in fathoms, feet, and inches; they spend page after page discoursing on instruments that should have been forgotten long ago; they try to antagonize theory and practice by detailing such calculations as that a certain vein will contain 2,003.907 pounds of galena per square fathom, and then reduce this amazing quantity to hundredweights, quarters, and pounds. Nothing can be more unscientific, or, for that matter, less businesslike, than unwarranted assumptions of accuracy; it is, perhaps, the greatest curse of applied science. Here we have a calculation to thethousandth part of a pound, when there is probably an unavoidable error of two hundred pounds. What shall we say of a man who explains how to measure the depths of shafts to the hundredth part of an inch by means of short brass rods screwed together...

Jan 1, 1909

When the Mining Bill came before the Victorian Legislature not so many months ago, the question arose whether mining managers required education, and to what extent. Some members of the House expressed themselves in a way which appeared to leave the impression that mining managers would be all the better if they were not brought up in a scientific school.To try and prove what we owe to science I will give a short history of colonial mining from the earlier period to the present time and compare results.I believe I am right in saying that South Australia is the pioneer colony in mining and to her belongs the credit of not dnly being the first mining colony, but also that her beginning turned out so successful, as the history of the Burra Burra copper mine will testify. At about the same time a little galena mining was carried on nearer to Adelaide, but as this did not prove a success and was only worked by tributing parties, little notice was taken of it.

By Reeves M

A review of the literature available in English on kriging and geostatistics is given with the references cross-classified by their subject matter for convenience and ease of use.

Jan 1, 1979

CONTENTS: Broken Hill The mixing stations.Operating and mixing apparatus.Pulp distribution.Stope preparation.Filling procedure.Consolidation of old fill.Drainage:Pulp density tests. Life of sand pipe lines.Results.Advantages and disadvantages.Conclusion and acknowledgments.General remarks on South Limited.Mining methods.History of stope filling in Broken Hill.Need for a new and better filling method and transport system.Initial experiments with hydraulic stowing.Source of the sand.Water Supply.Signalling system.GENERAL REMARKS ON BROKEN HILL SOUTH LIMITEDThe South Mine, property of Broken Hill South Limited, is situated at Broken Hill, N.S.W., Australia, towards the southern end of the main lode.The leases (M.L's 7 and 8)' cover a length of 2,400 feet along the lode outcrop and the workings extend, at this date, to a depth of 1,940 feet below the collar of the original main shaft and to 825 feet below sea level.Mining operations have been continuous for about 58 years and during this period nearly 12.5 million tons of ore have been mined. The monthly tonnage extracted approximates 30,000 tons in normal times.The ore is a mixed sulphide containing galena and marmatite; the gangue minerals are principally calcite, rhodonite, quartz and garnet.A typical assay for a monthly period is 14·40/0 Pb., 5·6 ozs. Ag., and 11· 60/0 Zn. The whole of the ore is concentrated on the property by combined gravity and flotation methods. The lead and 'zinc concentrates produced are railed to other centres for the extraction of the contained metals.MINING METHODSMining practice throughout the field varies only in minor details. The ore-bodies forming the Broken Hill Lode lie within complex folds arranged along a shear and vary in size and mineralogical associations, but all the mines have similar types. Some of the ore-bodies have weak walls, but the chief difficulty in mining is caused by "heads" and "flaws" in the ore.Besides these local weak areas there are ground movements-referred to later-of varying magnitude extending throughout the central portion of the lode where the large ore-bodies, several hundred feet wide, approached the surface.

Jan 1, 1944

By R Byrnes, P Hensley

The outstanding environmental management initiatives undertaken by Novacoal at its Western Main Site near Lithgow in New South Wales over the past five years are detailed in this paper. These initiatives have been based on a combination of proven and innovative investigation and implementation techniques, close consultation with regulatory authorities and full support by colliery management. The results of these initiatives have enabled the colliery to exceed its pollution control obligations from a base well below industry standards. The initial poor condition of the mine was the result of over 50 years of traditional mining which paid little regard to environmental management. The transformation of the colliery within such a short period, with limited capital, is considered a model for the N.S.W. coal industry.

Jan 1, 1995

By Greaves M. C

X-ray fluorescence spectroscopy used for the analysis of mill samples results in improved control of flotation concentrators.Techniques and equipment for sampling pulp streams, filtration and drying, grinding, briquetting and X-ray fluorescence analysis of samples have been developed.The current methods in use permit the analysis for lead and zinc in six pulp samples within 30 min total elapsed from the start of sampling. The X-ray method gives a precision at least equal to the former routine wet-way assay methods.The equipment is used also for pilot plant control, as a means of solving complicated analytical problems and in the rapid qualitative analysis of exploration samples.INTRODUCTIONIn milling and concentrating operations, classical methods for the assay of lead and zinc have been mainly of use for accounting purposes and for the post-mortem examination of plant operations, but have been of little value for rapid mill control. Where attempts have been made to apply these methods to control assaying, it has been necessary to modify the procedures and introduce short cuts which have tended to reduce their reliability.Even with these shortened procedures, the time taken to obtain a limited amount of information rendered them of little value for the control of milling operations where sudden, large fluctuations can occur. In recent years, a number of new and rapid analytical techniques, based on physical rather than chemical principles, have been introduced.These include direct reading emission spectroscopy, x-ray fluorescence spectroscopy and atomic absorptionspectroscopy.

Jan 1, 1964

Contact Angle Measurements on Lignite Surface

Sep 13, 2010

The use of scrapers in mining and earthmoving operations is not new, in fact they are one of the earliest methods of bulk earthmoving. A single machine which can load, haul, and dump material with a minimum of ancilliary support is a highly productive and cost-efficient method of earthmoving. In recent times scrapers have been unpopular due to perceived problems and operational limitations, but the last couple of years have seen a resurgence in the use of scrapers in the Bowen Basin as a primary prestripping tool. The main operational limitation of scrapers is the economic operating range. maximum productivity and lowest cost per bcm is achieved on short leads, as the lead distance increases the cost per bcm quickly reaches and then overtakes that of an truck-excavator fleet. The geometry of a ætraditionalÆ coal mine does not readily allow short leads for prestrip fleets due to the nature of dragline stripping operations. The strip arrangement means that material has to be taken around the end of the pit, meaning a longer haul distance than the actual point-to-point distance between load and dump. This can be alleviated by using pit bridges, however these can cause spoil problems for draglines if not properly planned and have been avoided by many mines. Due to the economic haul distance limitation of scrapers, truck-excavator fleets have become the normal method utilised. Currently more geologically complex mines are opening up, which do not allow traditional down-dip strip mining to occur. Cross-dip mining methods allow for short leads between prestrip loading and dumping areas, hence scrapers and bulk doze are realistic alternatives to a truck-excavator fleet in the prestrip environment. Keeping the lead distance to a minimum a fleet of 657Æs can move material at a very low cost. The other main operational limitation of scrapers is the type of material that can be economically excavated. Hard material can lead to damage to the bowl, free-flowing sand will not readily stay in the bowl leading to reduced load factors. Ripping the material with a dozer prior to excavating can lead to improved loading time, and greatly reduced GET consumption. When considering scrapers for prestrip operations a number of things must be considered: is the lead distance within the economic haul distance? should twin power (push-pull) or single power (dozer pushed) scrapers be used? do I need to rip, what should I rip with? what ancilliary support is required? is there another system already available on-site which is currently under utilised? This paper considers the parameters under which large twin power scrapers are the most effective way of undertaking prestrip operations.

Jan 1, 2003

In the plumbing of vertical shafts the methods employed and equipment used, are generally made to best suit existing conditions. Undoubtedly, there is no method that can be called standard or that can be used with equal ease and success on all shafts. At the Mount Isa Mines Limited property in Northern Queensland, Australia, local conditions have presented no major difficulties to be overcome in shaft plumbing work. In fact, compared to those at many shafts, the problem has been rather simple. There are three vertical shafts connecting main mine workings, with the greatest plumbing depth for any single lift, 350 ft.Other conditions pertaining to plumbing work have been generally normal.The method we have employed is, in principle, similar to the Weisbach orientation method with a variation that does not necessitate damping of the wires to bring them to rest. Although conditions encountered have not been such that damping the wires would have been inconvenient, we feel we have saved much time and eliminated unnecessary...

Jan 1, 1940