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By K Ehrig, C Lower, V Liebezeit, M Smith, E Macmillan

"Minerals, minerals, minerals. Elements occur in the earth as minerals. If local physical, chemical and structural conditions are conducive to concentrating these minerals to sufficiently high abundances in the earth’s crust, a mineral deposit will form. If technology is available to extract metals from the minerals economically, then you have a mineral resource that will be mined and processed. Determining which minerals are present and quantifying their abundances, textural characteristics (grain size and shape) and how they are intergrown with each other is the realm of the mineralogist. Geologists use this mineralogical data to understand how the mineral deposit formed, how to find high-grade zones within the deposit and where to find other mineral deposits. Metallurgists use this data to design, operate and optimise processing facilities to extract metals from the minerals. The types, quantity and precision/resolution of the mineralogical data required by geologists and metallurgists are different, but are not mutually exclusive of each other. Fortunately, measurement technology is available that is relatively rapid, high volume and low cost, thus enabling ore and gangue mineral characterisation at a historically unprecedented scale of a mineral resource.CITATION:Ehrig, K, Liebezeit, V, Smith, M, Macmillan, E and Lower, C, 2014. Geologists and the value chain – how material characterisation by modern mineralogy can optimise design and operation of processing facilities, in Proceedings Ninth International Mining Geology Conference 2014, pp 5–14 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Aug 18, 2014

By J Battista, J Grace, I Brunton

The need to better understand and develop strategies to improve instantaneous shovel productivity at the Cadia Hill Open Pit Mine (CHM) instigated the development of the æShot to ShovelÆ project. This project has involved the implementation of a drill and blast (D&B) information management system to capture current and future experience. Equally important has been the manual monitoring of shovel productivity and direct use and analysis of high precision GPS and productivity data logged by ModularÆs Dispatch System. The analysis of this type of data was facilitated with the application of GIS based software (ie MapInfo). This has shown to be a powerful medium to display, interpret and assess this type of spatial information on a blast-by-blast basis. Cadia HillÆs well-defined D&B processes supplemented with the application of the above systems are providing a unique capability to assess and better understand the impact of both muckpile conditions and operator proficiency on instantaneous loading productivity. This is facilitating the definition of appropriate optimisation strategies in both drilling and blasting and operator proficiency training. This paper gives a summary of the work conducted in the æShot to ShovelÆ project, describes the engineering tools being implemented and discusses preliminary findings and their practical implications.

Jan 1, 2004

By H Hoogvliet

The Goondicum Crater industrial minerals deposit is located about 30 km east of Monto, Central Queensland, Australia. Early exploration programs in the 1990s found alluvial ilmenite along the banks of the Burnett River. This mineralisation was traced upstream to the Goondicum Crater. The Goondicum Crater is a topographic feature centred on a roughly circular 6 km diameter layered gabbro complex. Significant ilmenite, apatite, titano-magnetite and feldspar mineralisation are present in a weathered horizon up to 25 m thick. After several drilling campaigns in the Crater and subsequent feasibility studies, the project was developed by Monto Minerals Ltd, an ASX listed company, in 2007. However, the project never achieved production performance expectations and ran out of commissioning funds. The company subsequently went into voluntary administration in August 2008.In 2009, the RMM Capital group, of Brisbane, took control of Monto Resources Pty Ltd, and renamed the company Belridge Enterprises Pty Ltd (Belridge). Belridge commissioned a redevelopment study aimed at recommencing mining and processing operations. As part of the redevelopment study the authors planned a drilling campaign, managed a quality control program and developed a block model. This paper describes the drilling program, analytical procedures, quality control procedures and the preparation of the block model.The block model for the resource estimate was created using 1 m high blocks, wireframes defining the main material types, and 2.5 m thick horizontal search ellipsoids with a radial pattern. The deposit was ‘flattened’ prior to modelling. To assist with the economic evaluation of the project, each block in the model was assigned a net dollar value based on economic parameters provided by Belridge, including anticipated revenues and costs. This modelling technique allowed for efficient investigation of various scenarios and was used extensively in the development and optimisation of the project’s financial model. At a zero net value per block, comparable to a break-even cut-off grade of four per cent ilmenite equivalent, the Indicated plus Measured resource is estimated at 51 Mt, averaging 4.1 per cent ilmenite, 1.9 per cent apatite and 2.5 per cent titano-magnetite.

Oct 5, 2011

The last decade has seen a very rapid development in TBM tunnelling. Some trends are purely technical or economical and others relate more to preferences of different interests. Power levels have more than doubled and thrust levels too. Shield machines are developed to be able to handle harder rock and the open TBMs are made more feasible for `difficult' rock. What is right and what is wrong is more a matter of opinion, but one thing is certain: TBMs now are a useful tool and no longer an experimental work-shop for the enthusiasts.This paper highlights some recent developments and indicates some probable future ones. A few features that have increased the open TBMs' ability to cope with ever harder rock and also to overcome problems with poor rock are discussed in detail, using the Atlas Copco JARVA Mk 27 -the most powerful TBM built so far - as a reference.

Jan 1, 1993

By G Clarke

Commissioning of the Cannington processing plant began in October 1997. The nameplate capacity (of 1.55 million tonnes of ore per annum) was achieved relatively quickly. Since then (like many mines) the operation has strived to increase throughput and improve valuable metal recoveries, to offset declining head grades and lift the value of the operation. The processing plant now has the capability of treating over 3.2 million tonnes of ore per annum and in financial year 2005/06 the combined concentrate production exceeded 600 000 wet tonnes, approximately 80 per cent above concentrate output in the first full year of operation (at the design feed rate). This improved performance was achieved by making changes and additions to each of the major unit processes û primary grinding, flotation, leaching, filtering and paste fill preparation. The changes have included: adding a fines flotation circuit, expanding the grinding circuit, adding a pebble crusher, switching from continuous to batch leaching, building paste conveyors and decommissioning the column flotation cleaning circuits. This paper reviews these changes, outlines the current operating practices and discusses the challenges or opportunities that remain.

Jan 1, 2007

By P G. Greenhill

The Wonawinta silver project near Cobar in NSW is under development by Cobar Consolidated Resources Limited (CCR). RMDSTEM Limited is part of the owner’s team for feasibility, design, engineering, construction and commissioning.With a 51Moz resource CCR is one of the largest pure silver players in Australia. A probable reserve of 14.3Moz has been defined for a mine life of approximately five years. The silver mineralization is contained in host rock composed of clays and oxidized limestone. The ore also contains on average 1.3% lead as cerussite, and other minerals. A simple circuit consisting of slurrying of the ore, gravity treatment of the coarse fraction to recover lead, silver extraction using CIL, elution and the Merrill Crowe silver recovery process, has been developed.The “value engineering” approach to this development pioneered over the past decade by RMDSTEM has meant that RMDSTEM has delivered the bankable feasibility study at a cost of $0.07 per resource ounce. It is highly cost effective making efficient use of shareholders funds as well as being very time efficient. This paper describes the application of the value engineering approach to the development of the Wonawinta project.

Aug 8, 2011

By Kurita K, Tanaka T

In order to clarify the gas flow and motion of coke and reaction in the raceway, the mathematical raceway model was developed. This model consists of the equations of momentum and continuity of gas and coke. The simulated results were compared with the results of the cold and hot experimental model. The relationship between the blast volume and the raceway size, the pressure distribution and the velocity distribution of coke are in good agreement with the experimental results. Moreover the equations of reaction and heat conservation were simultaneously calculated with the dynamic equations. Distributions of gas composi- itions and temperature were simulated and found to be in good agreement with the distributions of gas compositions of CO, CO2 on the tuyere level measur- ed in the hot experimental model.

Jan 1, 1981

By Beattie T. A

The ability of explosives to fragment rock has been assessed in small scale trials at the Granite Rock quarry, Baimsdale, Victoria. Three 65 mm diameter holes were fired simultaneously in a five metre bench, and the rock collected, screened and weighed. The mass of fines increased as the explosive strength increased in the series 30(10 ANFOPS

Jan 1, 1990

By J L. Stacey

The diverse priorities, drivers and concerns of multiple stakeholders in the minerals industry complicate the integration of sustainable development considerations into mine design, as well as operational and strategic decisions. The ability of the industry to address all role-playersÆ needs, or indeed, to achieve consensus among all role players on the plethora of sustainable development issues seems a noble yet unattainable goal. One of the difficulties in assessing the relative importance of sustainable development issues across many stakeholders is the inevitable lack of impartiality in valuing these issues. Starting from a premise that transparency and fairness of the process are absolute prerequisites for progress, but that consensus is not, an approach has been developed in which all stakeholders are asked to assess the importance of all other stakeholdersÆ priorities, excluding their own. The approach recognises that stakeholders have different levels of contribution, understanding, vested interests, and perceptions of legitimacy and entitlement, across the diversity of sustainable development issues and decision criteria. Using Triangular Value Analysis, the relative weightings of each of the stakeholderÆs priorities are determined through a regression-like technique. The uniqueness of this approach is the manner in which self-assessment bias and overemphasis of stakeholdersÆ own priorities are avoided. The methodology can be used for both internal and external stakeholders, and in conjunction with other group decision making techniques, such as the nominal group or Delphi techniques. This paper will illustrate how Triangular Value Analysis may be applied in the minerals industry to determine priorities in various decisions relating to potentially conflicting sustainable development priorities within the industry.

Jan 1, 2009

By Vynne J. F

Drill monitors for blasthole and exploration drills have been available to the mining industry since the 1970s. The early monitors were pen strip chart recorders which were developed for the oil drilling industry and adapted to mining. They recorded drilling parameters such as depth, pull-down pressure, torque, RPM, and bailing air pressure. While these recorders could generate a large volume of paper, the amount of useful data was minimal. The data was not summarised and required an engineer to interrupt the chart traces. Being a mechanical recorder, the devices were also susceptible to frequent failures.

Jan 1, 1993

By G J. Harbort, K Lam, C Sola

The relationship between the geology of porphyry copper deposits and their processing performance is an area of interest. Being able to predict comminution properties of the ore from physical characteristics and geological descriptions would allow an increase in the precision of capital cost estimates, operating cost estimates and throughput rates. This geometallurgical approach would reduce the requirements for expensive comminution tests.As the comminution circuit is the highest capital cost item in the plant and a possible throughput bottleneck, understanding the variability in hardness within the orebody is critical. A geometallurgical model allows calculation of ore hardness values in mining blocks from ore characterisation data. This model subsequently uses a combination of simulation and power-based approaches to relate ore hardness and flotation feed size to grinding circuit throughput.This paper reviews the geometallurgical models developed for seven porphyry copper deposits and discusses the strengths and shortfalls of the methodology and similarities and differences between the different deposits.CITATION:Harbort, G J, Lam, K and Sola, C, 2013. The use of geometallurgy to estimate comminution parameters within porphyry copper deposits, in Proceedings The Second AusIMM International Geometallurgy Conference (GeoMet) 2013 , pp 217-230 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 29, 2013

By Wymer DG

The concept of hydro power in deep mines is based on the exploitation of the hydrostatic head that can be gained as refrigerated cooling water descends in shaft pipe columns from the surface, to provide hydraulic power for machines at the working face. This paper describes the work done on two important aspects of the controlled distribu-tion of the high pressure water within a mine, namely the control of pressure under normal operating conditions, and the control of flow in an emergency situation following a pipe breakage. Suitable methods of control have been determined using theoretical techniques to model the steady and unsteady flow behaviour of the water in the pipeline, and taking into consideration the environmental constraints on the types of control devices that can be used. The preferred approach is one in which the high pressure water itself is used as the control medium. The control valves themselves can be fairly conventional in design, but in the case of pipe break protection it is shown that a less conventional approach based on the use of a hydraulic fuse gives improved control performance.

Jan 1, 1985

By M Ind, B Usher

Environmental regulators are increasingly adopting risk-based approaches to protect aquatic ecosystems. The Australian and New Zealand Environment and Conservation Council (ANZECC) and the Agriculture and Resource Management Council of Australia and New Zealand (ARMCANZ) (2000) introduced a risk-based approach to water quality guidelines that use decision frameworks to adapt water quality guidelines to local environmental conditions. Environmental quality objectives are no longer a simple ‘pass or fail’ number such as restricting total suspended solids (TSS) concentration to a specified limit for a particular rainfall event. This approach ignores spatial and temporal variability and the complexity of aquatic ecosystems. The risk-based approach establishes levels where adverse effects may occur. If these objectives are not met, further risk-based investigation is undertaken to assess the potential impact to the ecosystem. Klohn Crippen Berger (KCB) developed a dynamic simulation to predict the variability of sediment discharges, which is applicable for risk-based impact assessment of aquatic ecosystems. The application of the methodology over the life of a mine site is illustrated using a proposed South Pacific mine.The site location is in extremely rugged terrain with a high annual rainfall of approximately 4.7 m. There were two major sediment ponds proposed to reduce sediment discharges. A sediment and hydrology model was developed in Goldsim to provide daily estimates of run-off flows and sediment concentrations. A modified algorithm based on the Australian water balance model was created and incorporated into the Goldsim model and calibrated using recorded field data.The sediment module was developed based on a Revised Universal Soil Loss Equation (RUSLE) assessment, an annual prediction of soil loss over a catchment. A land-use type erosion vector was developed for different land-use types and for each of the subcatchments, a subcatchment erodibility vector was calculated. This vector and the daily rainfall erosivity factor were used to estimate the daily soil loss. The estimated soil loss and the modelled run-off yielded predictions of daily sediment concentrations. Finally, a sediment settling module was used to predict the daily efficiency of the sediment ponds and hence discharged sediment concentrations.The results of this modelling form the first part of a quantitative risk-based assessment into suspended solids impacts. The second part is the assessment of the effects of these predicted TSS concentrations on aquatic ecology. As part of the feedback-loop required in a risk management framework, if the environmental quality objectives are not met then further management decisions and actions may be required to reduce the risks presented by suspended solids. This may include modifications to: the mine-development plan; construction techniques and scheduling; processing techniques; rehabilitation strategies; or hard-engineering solutions such as sediment basins or flocculation.The Goldsim water-balance model provides a quick and efficient method of testing potential remedial actions on predicted sediment loads and concentrations. In combination with a cost-benefit assessment, options for reducing sediment releases from the mine site can be effectively and quantitatively compared thereby providing mine operators with a basis for decision-making. Regulators can also be satisfied that potential impacts to aquatic ecology have been comprehensively assessed and the necessary management decisions have been initiated to limit risk to the environment.CITATION:Ind, M and Usher, B, ?2014. A dynamic sediment simulation to predict the variability of suspended solids concentrations over life-of-mine for application to a risk-based environmental assessment, in Proceedings Life-of-Mine 2014 , pp 191–204 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

By C Zhang, I Canbulat, G Fan, D Zhang, C Wang

A clear understanding of the intensity of coal and rock burst is the basis for future research on burst mechanism and control. There has been a wide variety in the description of coal and rock burst damage at different countries using multi-methods, which makes the common understanding even more challenging. Therefore, this paper presents a broad review on the quantifications of intensity of coal and rock burst and seismic risk around the world, considering critical factors including seismic energy, magnitude, peak particle velocity and ejection velocity. It is found that the seismic energy of coal and rock burst can widely range from 0.002 MJ to 60000 MJ, with equivalent Richter magnitude from -1 to 4. The daily seismic energies can be used for seismic risk potential assessment, with energy levels from 0.1 KJ to 10 MJ, which is much lower than the burst sources. The magnitude of the seismic events can be also estimated based on the weight of damaged coal mass and human senses of vibration and sound. For the seismic intensity represented by peak particle velocity (ppv), it keeps constant within fault radius and attenuates with a speed of 1/r4 and 1/r in near and far field respectively, thus it is possible for a small seismic event to induce considerable ppv causing severe damage if the epicentral distance is small enough. There has not been a strong correlation between the ejection velocity and ppv, as seismic energy is only one of the energy sources that contribute to the kinetic energy of burst damage. CITATION:Wang, C, Zhang, C, Canbulat, I, Zhang, D and Fan, G, 2018. Intensity quantification of coal and rock burst risk – a review, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), pp 223–233 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

LITHOPROBE is a national, collaborative research grogram with the general objective of understanding the teotectonic evolution of the North American continent through multidisciplinary lithospheric studies in carefully selected areas of Canada. Six transect areas are investigating Precambrian evolution, although only in two of these is the research well evolved. The Archean Kapuskasing Structural Zone in Ontario is confirmed as an upthrust slice of upper to mid crust exposed at the surface. The Late Proterozoic Keweenawan mid-continent rift is shown to be the deepest known rift on Earth and the Grenville collisional zone of Ontario and Quebec involves crustal scale imbrication and ramping of deeply buried rocks to the surface. Two transect areas are investigating Phanerozoic evolution. In the Newfoundland Appalachians the geologically defined tectonostratigraphic domains do not coincide with lower crustal blocks defined by seismic reflection data. The Southern Cordillera Transect in western Canada is examining the nature, timing and dynamics of the assembly of the Cordillera, and particularly the role of accreted terranes. Work in the eastern and central segments has extended the known western limit of the North American craton at least IOO km westward and crustal-scale ramps associated with metamorphic core complexes have been identified.

Jan 1, 1990

Dr Wark said: I have not come to Broken Hill to tell you how to conduct flotation operations; indeed, during my short stay here I have already learned much concerning the process, of the many difficulties which have been overcome, and of those still awaiting solution. My purpose tonight is rather different. All who have been concerned with the operation of the flotation process must have wondered, like myself, why the process is possible at all. In particular, why can minerals which are heavier than water be made to l10at to its surface; why do certain minerals float while others do not; and what are the functions of the added chemicals?I have been asked to describe tonight some of the ways which have been adopted in the Melbourne University laboratory in an endeavour to find answers to these. questions. Knowing that you are just as interested in them as we are and, furthermore, appreciating that were it not for the co-operation of the Broken Hill companies our researches would not have been possible, I regard it as a high privilege that I should have been invited to tell you of our work. Before doing so, I would like to tell you the reasons why the work was started and for whom it has been carried out. Soon after the flotation process had been successfully exploited on a commercial scale a number of investigators sought to determine the theoretical basis upon which it rests, and our knowledge of the function of the added chemicals has been considerably broadened by the published accounts of many workers, particularly in recent years of those working in American universities.The Australian metallurgist played, as you know, a part second to none in the early development of the process, and Australia's mining fields had already reaped such rich rewards from it that, late in 1929, it was felt by some of the leaders of the industry that we should take a larger part in the efforts being made to extend the knowledge of the principles upon which the process is based.Accordingly, several companies - the Broken Hill South, the North Broken Hill, The Zinc Corporation, the Electrolytic Zinc and the Mount Lyell Companies - established a laboratory in the chemistry department of the University of Melbourne for the purpose of investigating the principles underlying flotation.Subsequently another British company, the Burma Corporation Ltd, expressed a desire to co-operate.

Jan 1, 1994

By R Lastra, Y Choi, C Hamilton, P Kondos

Hydroseparation (http://www.cnt-mc.com) was used to concentrate sized fractions (from <38 ¦m to 150 ¦m) of various ore products ahead of carbon-in-pulp (CIP)-treatment. The resulting size-by-size concentrates were mounted as monolayer polished sections and subjected to automated unattended precious metal searches by image analysis (see Lastra, Wilson and Cabri, 1999). Systematic variations in Au-deportment permit quantification of Au reporting as discrete grains from fresh-feed through to pressure oxidation (POX)- and CIP-feed. Application of hydroseparation, image analysis and assays to characterising tailings (from <10 ¦m to 106 ¦m) from four mine sites is also described. Results are encouraging enough to predict that the combination of hydroseparation (HS) and automated image analysis could become a standard methodology for study of precious metal ores and metallurgical products.

Jan 1, 2008

By P Hagan, S Wang, D Li, B Loh

A study was undertaken to quantify the differences in performance between a full-length encapsulated cable bolt and a partially encapsulated cable bolt. Much research has been reported on the differences in cable bolt design and operational parameters such as borehole diameter and grout type with much of this based on the Laboratory Short Encapsulation Pull Test (LSEPT). However, there is a gap in knowledge surrounding the effect of anchorage length on load transfer and cable bolt performance particularly with respect to the role of the bulb in modified cable bolt designs. The objective of this study was to expand the existing knowledge base of cable bolt performance with the intent of developing a revised design criterion. Alongside a comprehensive review of current cable support theory, design and practice, a series of pull tests was undertaken to compare each anchorage method using a high capacity modified cable bolt. The results serve to confirm earlier work on fully encapsulated anchorage. Both the peak load capacity and stiffness of the fully encapsulated cable bolt were nearly double that of the partially anchored cable bolt. When the tests were repeated in an oversized borehole, while there tended to be more variation in performance, there was little significant difference in the mean results. In addition to anchorage length, there are other factors that contribute to cable bolt performance including in order of sensitivity: embedment length, water-to-cement ratio of the grout, type of grout and borehole diameter. CITATION:Loh, B, Hagan, P, Li, D and Wang, S, 2018. A comparison of the performance of fully versus partially encapsulated cable bolts based on laboratory-scale testing, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), pp 291–302 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

THE following paragraphs represent an endeavour to describe, briefly the equipment used for the manufacture of sulphuric acid and superphosphates by the Corporation.SULPHURIC ACID PLANTS.Two separate units are in operation, No. I Plant working on sulphur dioxide generated from pyritic ore, No. 2 Plant working on sulphurous gases obtained from the Huntingdon-Heberlein desulphurizing process. The latter plant is unique in being the first installation for the successful use of these gases.

Jan 1, 1918

Constraints on the mineral industry are best treated as issues that have to be understood and managed in partnership rather than in conflict with communities. The Zapopan development at Mt Todd in Australia and the Martha Hill development at Waihi in New Zealand are but two of many recent successful examples at the local level. However, at the national level, the issues are more complex and more difficult to resolve because the most influential stakeholders are now the urban electorates and governments defer to their perceptions when making decisions and policy.

Jan 1, 1995