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The Australian mining industry is at an interesting stage in its development. Of the large number of mining companies in Australia, some are still solely domestic in their focus. others have made their first tentative forays offshore, and others are global players of significance in the world industry. It is not long ago that the entire industry was almost exclusively domestic in its focus. Very few companies before the early 1980s had ventured offshore, and those that did so were considered quite risque. The initial moves were made mainly by large companies who could afford to lose the funds expended in getting started in a range of offshore locations.

Jan 1, 1995

By A Purchase, C Stacey

The procedure for operation of deluge systems installed in road tunnels is still a subject of debate. The work undertaken in this paper assists in the understanding of the effects of deluge in road tunnels, and thus aims to help inform the development of operational policy. Analysis was undertaken using computational fluid dynamics (CFD) simulations to help explore the deluge interaction with the tunnel ventilation (including smoke exhaust) and combustion products. It was found, for the scenarios considered, that: Deluge activation can decrease the required critical velocity for smoke backlayering, and this in turn can improve the effectiveness of a smoke exhaust system.The dominant parameter for deluge effectiveness is the vehicle configuration, with shielded scenarios (such as a fire in the passenger compartment) showing almost no water reaching the fire. The water delivery rate (5 mm/min versus 10 mm/min) has only a minor effect on the smoke duct damper inlet temperatures and downstream smoke temperatures for small fires (5 MW). For large fires (50 MW) the higher water delivery rate gives slightly improved performance (lower damper inlet temperatures and lower downstream smoke temperatures). A one-dimensional transient tunnel model incorporating different operational and deluge response policies (ie deluge activation times) was developed. It was used to examine the influence of different operational parameters on life safety risk and tunnel damage risk. It was found, for the scenarios considered, that: The life safety risk for different scenarios has a sensitivity to deluge activation policy with the case of delaying the deluge activation for a long time giving the worst outcomes. However, the most critical parameters for life safety risk are operator response time (for all response activities, not just deluge) and the type of fire (configuration, size and growth rate).There is a reduction in risk of tunnel damage when the deluge is activated earlier, although the fire configuration (ie whether or not the seat of the fire can be reached) has the greatest influence on the outcome. It is concluded that the deluge activation policy should be case-dependent. It will depend on the tunnel, the safety systems provided, and most particularly the vehicles involved. The current policy in Australian tunnels is for manual activation of the deluge by the tunnel operator as soon as practical after the fire is confirmed (see also PIARC, 2007). This is a good policy. However, future work may be helpful to improve the skills of operators to make the best judgement as to when deluge should be activated, balancing all risks. This work could include research to further the understanding of deluge and fire in road tunnels, training programs and consideration of historical fire events.

Jan 1, 2008

By J Mavrogenes, C J. Spandler, S M. Eggins, K Worden

Major occurrences of platinum group minerals (PGM) are in crustally-contaminated, huge, layered igneous complexes (Bushveld and Stillwater) and gabbroic intrusions (Norilsk); relatively minor occurrences include arc-related æzoned Alaskan ultramaficsÆ. In terms of arc-related provenances, the recognition of alluvial PGM in river and beach deposits of southern South Island (Mitchell, 1995), in situ in the Longwoods (Cowden et al, 1990), and the ultramafic-mafic layered Greenhills Complex at Bluff (Spandler et al, 2000) raise the possibility that some economically-significant PGM deposits may exist in New Zealand. The Longwoods and Greenhills are in the Brook Street Terrane which is a remnant of a primitive intra-oceanic arc system of Late Permian-Early Triassic age. The Terrane comprises volcanogenic sequences containing plagioclase- and clinopyroxenephyric basalts, high-MgO ankaramite and dolerite dikes, trondhjemite plutons, and basaltic to andesitic volcaniclastic and sedimentary rocks. The cumulate complexes contain early-formed olivine- and clinopyroxene-rich ultramafic cumulates overlain by anorthite and hornblende-bearing gabbros. Primary (isoferroplatinum) and secondary (sperrylite) platinum group minerals are preserved in chrome-rich spinel pods in basal dunite of the Greenhills Complex. Saturation during early fractionation of primitive high-MgO magmas rather than magma mixing seems likely for the primary PGM. Together with correlative terranes in Queensland and New Caledonia, the Brooks Street Terrane is an exposed cross-section of an extensive Permo-Triassic island-arc system. Most parental magmas were primitive island-arc tholeiites, but other primary magma-types include high-MgO ankaramites and trondhjemites û the latter formed by partial melting of lower crustal clinopyroxene-rich cumulates and gabbros, respectively. The parental ankaramites fractionated to form mafic-ultramafic cumulates and primitive to evolved melts of high-Al basalt to andesite compositions (Takitimus). The Brook Street Terrane is an analogue for modern intra-oceanic islandarc systems and allows detailed study of subvolcanic arc processes.

Jan 1, 2005

By R Yong, A McEwan, D G. Miljak, D Milinkovic, A Curtain, P J. Coghill, R Stefulj, B Lovric, G Roberts

The CSIRO has pioneered the development and use of certain classes of magnetic resonance (MR) for mining applications. The MR technique is a radio frequency-based spectroscopy that provides highly quantitative measurement of selected ore minerals. MR has many inherent advantages for bulk sensing in mining applications, including deep sensing penetration into most bulk ores with the use of non-contact sensors that are robust and tolerant of demanding mine conditions. The highly discriminating nature of the technique also provides the very desirable attribute of robust and simple calibration, that can often be performed prior to sensor installation. Rapid sensing (within seconds) at very low grade (few hundred ppm Cu) has been demonstrated, as well as sensing at high tonnage rate. Besides sorting applications, MR may also be applied to preconcentration applications involving very large volume sensing including: (i) haul truck sensing using portal arrangements, where truck destination assignment may be dynamically determined based on the truck grade, (ii) in-pit gantries used for loading trucks that may similarly be equipped with sensors for truck assignment and (iii) deep mine bench sensing, recently progressed through a CRC ORE project, where local bench grade is determined at the few-metre lateral scale and at depth prior to blasting, to aid selective blasting and ore extraction. MR sensor prototypes have been developed for each of these applications and have been tested in laboratory or limited field conditions. To inform the value proposition for truck or bench sensing, initial analysis of truck assignment improvement based on an analysis of in-situ mine bench grade has been performed for a porphyry style deposit. The prototype sensors, preliminary results and future technology development and objectives will be described.

Nov 10, 2020

Natural gas from the south west Queensland gas fields is now available in north west Queensland to fuel the development of many Carpentaria Mineral Province projects. Like these projects, the south west Queensland gas project, developed under the operatorship of Santos Ltd, has its own æMining CycleÆ. While the project is entering its third expansion phase, it is at the same time actively extending its discovery phase, with large programs of gas exploration and reserves definition. This paper outlines the history of the south west Queensland gas project, with particular emphasis on the relationship of the project to north west Queensland.

Jan 1, 1998

The excessively high cost of production in underground coal mines has made the survival of many coal mines around the globe economically non-viable. The global competitive coal market speaks itself of the desirability of a lower operating cost in conjunction with a higher productivity performance, particularly in underground coal mines, and calls for an optimal production planning under a host of constraints. Such a task of optimal planning is not an easy exercise like that of traditional planning based merely on intuition, experience and subjective judgement. It essentially demands a thorough understanding of the complex interaction of mine sub-systems for judicious application of optimisation tools and techniques available with operations research. A few large mines around the globe have made an effective use of a sizeable number of operations research packaged programs for optimal decision-making (Grayson, 1989). The success of practical applications of operations research techniques made in a variety of mining problems in large mines in different parts of the world will hopefully make inroads to smaller mines in years to come. The present paper is an addition in the series of such applications of operations research tools to mining problems, particularly with reference to an underground coal mine in India. The paper is based on research work (Jawed, 1990) and deals with the development and use of a mathematical model for production planning in underground coal mines under multiple objective environment subject to a host of constraints.

Jan 1, 1995

By Y Mita, T Iwama, R Inoue, S Ueda

In the iron and steel manufacturing industries, efforts are being made to achieve carbon neutrality by 2050, and the transition from a coal-based steelmaking process to that utilising renewable energy is being pursued. An alternative process in which directly hydrogen-reduced iron is melted in an electric furnace is being investigated. It is known that foaming slag reduces heat loss from the steel bath in electric arc furnace, but iron loss due to the suspension of steel particles in the slag is indispensable. To improve the separation of steel particles from the slag, the control of the slag viscosity is important. Although the slag viscosity has been extensively studied, in those studies the slag was considered to be a simple liquid. However, in actual operations, slag is a multiphase fluid consisting of solid, gas and liquid phases. Therefore, in this study, by measuring the sedimentation velocity of titanium, stainless steel and glass spheres in an aqueous glycerin solution containing bubbles generated by the reaction between NaHCO3 and C2H2O4, the apparent viscosity of the gas-liquid fluid was evaluated based on Stoke’s law. It was found that the apparent viscosity of the gas-liquid fluid is larger than the viscosity of liquid phase and depends on both the bubble volume ratio in solution and the density of the falling solid sphere, and the apparent viscosity was different from that previously obtained by the rotation method. The apparent viscosity derived from the sedimentation velocity of solid spheres changed depending on the specific gravity of the ball. This is because the apparent viscosity is derived from the velocity of a ball falling in a static bubble in this method, whereas that is derived from the force applied by a stationary flow in the rotational method.

Aug 21, 2024

The discovery of copper and nickel sulphides in the Riwaka Complex in 1967 led to considerable exploration activity by a number of companies. Various exploration techniques used by these companies are summarised and discussed. Activity of these companies shows that mineralisation is mainly confined to the southern, ultramafic section of the Riwaka Complex where geological mapping recognised sixteen units within, or associated with the Riwaka Complex. Significant pyrrhotite, pentlandite chalcopyrite mineralisation is restricted to biotite feldspar pyroxenites and to clinopyroxenite units. Lesser and more erratically distributed pyrite chalcopyrite pyrrhotite mineralisation occurs in poikilitic pyroxene hornblendites, melanocratic gabbros, and in marginal diorite lenses. It is suggested that a linear belt of layered ultramafic and mafic rocks described in Fiordland by Williams (1974) may be a southern extension of the Riwaka Complex. The Riwaka Complex has been classified as belonging to the Picritic subtype, (Tholeiitic suite), of Naldrett and Cabri, (1976), and as such it is concluded that it exhibits substantial potential for the discovery of economic copper and nickel deposits. It is considered that the complex is a multiphase differentiated intrusion emplaced in a major tensional fracture zone that developed in a relatively stable tectonic environment, namely a succession of middle Paleozoic shallow water shelf sediments. Based on sparse available evidence it is suggested that the Riwaka Complex was intruded in the lower to middle Permian. It is further suggested that the tensional fracturing was initiated by the onset of subduction process which were responsible for the development of the Permian volcanic arcs and ophiolite belt in the north west Nelson area.

Jan 1, 1977

I have chosen this topic for my address with the intention of preserving a rather extraordinary record of recurrent additions of capital in the financing of one of the world's important silver-lead-zinc mines. The recitation of the trials and tribulations which fore-shadowed the rise of Mount Isa Mines to a position of relative prominence in the realm of non-ferrous mineral production may, I hope, be of assistance to some of the younger members of the Institute who may be called upon during their careers to meet similardevelopmental and financial problems.Mount Isa Mines Limited was incorporated in New South Wales in 1924 with an Authorised Capital of 40,000 shares of £20 each.In November 1925 the Company acquired the leases and water rights of the Mount Isa Proprietary Silver-Lead Limited for 6,250 fully paid £20 shares. Shortly thereafter, but in the same year, the £20 shares were split up into £1 shares, thus bringing the Authorised Capital to £800,000.The leases purchased consolidated and brought under one management the principal ore bodies of the Mount Isa area.Transportation facilities were indispensable to the economic future of the field, so the construction of a railway extending the Government line from Duchess, 54 ,miles to Mo.unt Isa, was assured by the passage of a bill in October 1925 by the Queensland Parliament. Under the provisions of the so-called Mount Isa Railway Act the Company was required to idemnify the Government against national loss on this branch line for a period of 10 years.

Jan 1, 1953

By J S. Petersen

The occurrence of coarse gold particles leading to grade complexity and sampling challenges is a common feature of many gold deposits. Poorly designed sampling protocols applied to these deposit types can lead to an excessively high fundamental sampling error. Together with other errors, the fundamental sampling error contributes to the nugget effect. Proper sample collection, preparation and assay protocols are required to minimise this error, and hence reduce the total nugget effect. Reduction of the nugget effect is a key requirement for subsequent geostatistical resource estimates to be effective. A case study from the Nalunaq gold mine in Greenland is presented, which is characterised by notable quantities of coarse gold (>30 per cent +100 ¦m gold) hosted in quartz veins. Diamond drilling provides a good measure of gross geological continuity at practical grid spacings, but is not considered to represent the mineralisation effectively. On-reef development with face and bulk sampling, together with detailed geological studies were undertaken during the resource delineation phase. This contribution describes the nature of the Nalunaq deposit, its gold particle size characteristics, how sampling and assay protocols were developed (including QA/QC issues), application of GyÆs sampling theory and its calibration, and how the data was subsequently applied to grade estimation.

Jan 1, 2005

Laboratory tests were conducted to study the effects of thrust or pull-down force and rotary speed on the vibration signatures of a particular drill in a known rock type, and to determine how the vibration signatures could be used to assess bit wear. The vibration signatures were analysed using a Wavelet Transform analysis technique, which decomposes the signals in multi-bands of frequency and presents the results simultaneously in time and frequency domain. Results show that as the bit wears, large fluctuations in amplitudes in the high frequency ranges occur, and prominent peaks in the low frequency ranges were observed for a worn bit. The Wavelet Transform technique provides an appropriate and effective metrics for monitoring and evaluating the state of wear as drilling progresses through the post-processing of wavelet coefficients. This study provides a basis for the development of an on-line detection technique of bit wear in rock drilling through Wavelet Transform technique or time-frequency analysis that can be used in real time.

Jan 1, 2000

Drilling and blasting operations have historically been viewed as a necessary 'evil' part of mining, whose costs should be minimised by whatever means possible. In the past, when operations depended primarily on crushing and milling for ore re

Jan 1, 1998

By J W Shields

The aim of this paper is to present a concept or model regarding a particular geological environment where gold orebodies occur in the Pine Creek Geosyncline and indeed in many other pans of the world. The name GIGIACS (an acronym for Gold In Greywacke In Anticlinal CrestS) is proposed to label this concept or model. The name Saddle Reefs (which has been in use for many years) is used for gold-bearing quartz veins which often occur in conjunction with Gigiacs. Simple patterns formed by this type of mineralisation at the surface due to different configurations are illustrated. Some examples of Gigiacs and associated saddle reefs are presented from the Pine Creek Geosyncline together with examples from other parts of the world. This concept has been used successfully as an exploration tool and five examples are given. The terms Gicsiacs (for Gold In Carbonaceous Shale In Anticlinal CrestS) and Giliacs (for Gold In Limestone In Anticlinal CrestS) are also used.

Jan 1, 1994

By D S. Clarke, W M. Prebble

Potential waste rock products from the mining of epithermal deposits in the Hauraki Goldfield are characterised to facilitate their management. Hydrothermally altered andesites and their weathered near surface equivalents have been examined from the Golden Cross, Karangahake and Monawai gold deposits. These materials vary in both their clay content (smectite, illite, kaolinite and chlorite) and the degree of silicification resulting from alteration and weathering. The simulated degradation (slaking tests) of waste materials cannot be explained purely by consideration of clay content, siliciflcation, or the resultant variations in porosity.   Microstructure is considered to be essential in predicting the physical degradation of waste rock. The scanning electron microscope is an effective tool in such an investigation. Increasing alteration results in clay particles becoming more randomly orientated (matrix microstructure); this causes a reduction in the surface area of contacts between components resulting in increased potential for degradation. The extent of skeletal microstructure (commonly characteristic of weathering) is an important control on effective porosity and the long term potential for degradation. Management requirements for these materials include the minimisation of moisture content variations (with the prevention of initial drying being of primary importance) and the containment of sediments produced.

Jan 1, 1991

In 1939 at the annual meeting of the Australasian Association for the Advancement of Science, held at Canberra, a paper was contributed by E. de C: Clarke and H. A. Ellist in which a plea was made for more "facts" concerning metasomatism near ore-bodies in Western Australia. From time to time writers here, and in other parts of the world, have discussed the alterations in wall rocks of various reefs and lodes, but little has yet been attempted in the matter of accumulation of quantitative data, both chemical and mineralogical, and in the correlation and comparative study of this data. Such a detailed comparative study is needed to determine the economic value of a practical application of our accumulated knowledge of the phenomena of metasomatism.When in 1939 the opportunity offered for an examination of the core from 4 bores recently put down by the Big Bell Mines Ltd., to explore the ore-body of the Corinthian G.M. 10 miles N.W. of Southern Cross, Western Australia it was hoped that some small beginnings might be made of an accumulation of comparative and quantitative data regarding the metasomatism of the wall rock immediately adjacent to this ore-body.By the courtesy of the Big Bell Mines Ltd., the core from the 4 bores was delivered to Survey Headquarters, Perth;in the middle of June, 1939 and copies of assay plans of part of the underground workings at Corinthian, and of the results of assays of the bore cores, were also supplied by the management of the above company.It was not, however, until March, 1940, that it was 'found possible to investigate the core. At that time the writer's colleague, Mr. R. S. Matheson, conducted a: megascopic examination of all the bores and selected material from two of these for possible future chemical analyses. Late in 1940 the writer commenced a microscopic petrological examination of this material.AIM OF THE INVESTIGATIONThe object of the petrological part of this investigation was to determine whether from a megascopic and microscopic examination of the core, any evidence could be obtained indicating changes, in mineralogical composition...

Jan 1, 1942

By Bingwen Z, Fengyi K

The hydraulic-stowing mining method is most effective for mining thick coal seams. It is superior to the sliced cover- caving and artificial mining method and the fully mechanized sublevel-caving mining method for the following reasons - a much higher recovery rate is achieved, there is much less surface subsidence and roof pressure, there is no hidden danger of gob fire, and much less methane emission and coal dust problems, etc.. However, its superiority is overshadowed by its backward stowing technique which makes mechanisation of mining and stowing difficult, causes bleed water interference to production and to the environment and is uneconomic because of the high cost of stowing material. These disadvantages limited its application to coal seams that are difficult and not suitable to be mined by other mining methods. The remedy is in reforming it thoroughly to permit mining of otherwise unminable seams and this paper presents the reformation.

Jan 1, 1992

By S Hapugoda, J Manuel, N Ware, A Dehghan-Manshadi

The effect of titania (TiO2 ) addition on the sintering performance of hematite iron ore has been studied by doping pure TiO2 into a sinter blend. The results of laboratory-scale compact sintering tests confirmed the considerable effect of TiO2 addition on sinter strength and mineralogy. The tumble index measurements confirmed an improvement in the strength of the sinter in response to TiO2 addition. The melting point of the sinter was also affected by increasing the TiO2 content, indicating a possible relationship between coke breeze consumption and TiO2 on industrial-scale sintering of Ti-bearing ores. Analysis of the sintered structures using optical and scanning electron microscopes confirmed a general improvement in the overall pore structure and sinter melt characteristics with the addition of TiO2 to the sinter blend. An important feature of the sinter structure was the formation of a perovskite phase (CaTiO3 ) and an increase in the proportion of this phase in the structure as TiO2 levels increase.CITATION:Dehghan-Manshadi, A, Manuel, J, Hapugoda, S, Ware, N and Donskoi, E, 2015. Effect of titania on the sintering performance of hematite iron ores, in Proceedings Iron Ore 2015, pp 29–34 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

Coal is of tremendous importance for the Czechoslovak econ- omy. The current annual primary energy demand being about 109 million tons of standard fuel (1 ton of standard fuel - 7,000 coal = 29,308 GJ), coal satisfies almost two thirds of our fuel consumption. If compared with the distribution of resources in the world's fuel and energy pattern, the situation in Czechos- lovakia is significantly different, as shown in Fig. I. One of the causes behind the difference is that the Czechoslo- vak oil and natural gas reserves and, hence, their production are insignificant, so that it is necessary to import them. Brown coal will continue to play an important role as a prin- cipal domestic source of primary energy even in the future. While the share of nuclear power is increasing, brown coal represents strategic reserves in the fuel and energy balance.

Jan 1, 1989

In the new refinery, at the works of the Broken Hill Associated Smelters Proprietary Limited, situated at Port Pirie, South Australia, the refining routine is similar to that carried on in the old one in that bullion is progressively refined first for arsenic and antimony, then for copper and gold, then for silver, and finally for zinc. However, actual procedure differs in that each refining operation is now conducted continuously, whereas in the old refinery intermittent batch treatment was practised.The early experimental work was concerned solely with the development of the continuous desilverising process, which, in addition to continuous treatment, embraces the novel feature of conjugate solution formation with consequent production of a silver product relatively high in silver and low in lead.

Jan 1, 1932

By M Dixon, T OÆShannessy

Melbourne Water (MW) is responsible for a section of existing gravity trunk sewer servicing the Melbourne central business district, Docklands, Port Melbourne and other adjacent areas, known as the Melbourne Main Sewer (MMS). MW has determined that the 2.2 km long 110 year old sewer will not adequately service these areas into the future or provide the level of reliability needed. The Melbourne Main Sewer Replacement project (MMSR) involves the replacement of the MMS with a new gravity sewer main and six key manhole shafts, known as the Melbourne Main Reliever (MMR).The majority of the MMR sewer tunnel is situated south of the Yarra River and will be constructed using an earth pressure balance (EPB) tunnel boring machine (TBM) and will be lined with precast concrete segments. The tunnel will be 2.4 m internal diameter and will have a 1.8 m diameter glass fibre reinforced plastic (GRP) sewer pipe positioned within it. This project represents the first large-scale, modern, mechanised tunnel project in MelbourneÆs Yarra Delta Quaternary sediments. There is little precedence known to the authors of similar scale tunnelling projects in these particular geological units. During the recent detailed investigation and design stages of the project, significant effort has been spent on characterising the geotechnical conditions along the alignment and predicting the effects of the new tunnel on the existing environment. Some of the key design issues that have been identified and managed through the design process include short-term surface settlement due to tunnel excavation and the predicted effects on surface infrastructure, potential spalling of the steel fibre reinforced concrete segments under full TBM ram loads and tunnel lining design in geological units with highly variable stiffness.Construction of the new MMR sewer tunnel is expected to commence in mid-2008 with a capital cost of approximately $160 million. Sewer system commissioning is scheduled for completion by early 2012.

Jan 1, 2008