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By S R. Williams

There is a sense of geometallurgy being new; a new methodology for mining project development and improved operational strategy. One of the main challenges that any ænewÆ technology faces is a validation of the value and the need to produce case studies. However, producing case studies can often be problematic particularly given the long cycle from mineral deposit project, through feasibility and construction to stabilised operation of a mine.However, the roots of geometallurgy go back quite some time. Successful practices with geometallurgy can be seen from as early as the 1980s. Many times those practices were not called geometallurgy but something else and, in other cases, what can be seen are various components of the geometallurgical ævalue chainÆ.This paper will analyse a selection of published past practices from a geometallurgical perspective to demonstrate the value realised from the application of this methodology. The paper will then make some general comments on where this history of work in geometallurgy has lead us to and what are the challenges today for the geometallurgical effort.CITATION:S R Williams, 2013. A historical perspective of the application and success of geometallurgical methodologies, in Proceedings The Second AusIMM International Geometallurgy Conference (GeoMet) 2013 , pp 37-48 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 29, 2013

Five Hypotheses are given for factors influencing long-run metals price forecasts. 1 . Geologists succeed when given the money. 2. Better understanding of a metals market depresses its price. 3 . Statistical techniques get forecasts wrong. 4. Long-run metals prices are related to crustal abundance. 5 . Economic cycles affect metals prices more than is realised. These are then framed within the transition between eras as influenced by apparent long waves in economic activity. Innovation surges during the transition between eras. The transition to the 5th Wave since the Indus- trial Revolution 200 years ago is now underway. Finally, price projec- tions are given both for the 5th Wave and 200 years from now on the assumption that a similar monetary measure to today will be then extant.

Jan 1, 1988

By L Bergin, D J. Williams, S Islam, T A. Vangsness

The flooding of open strip coal mines in the Bowen Basin and Hunter Valley Coalfields of Eastern Australia has the potential to soften the spoil and floor materials to produce “mud”. This mud can act as a slip plane or weak zone when spoil is dumped into it, resulting in geotechnical instabilities. Once mud has formed, typical handling techniques include its costly removal by mechanical means, or its isolation and capping.There are little data available on the moisture state and shear strength of the capped mud. To investigate the effectiveness of isolation and capping, research has been conducted using a large slurry consolidometer (150 mm in diameter by up to 410 mm in height) to simulate capping in situ. Once consolidated, the mud was subjected to shear strength testing in a direct shear box measuring 60 mm by 60 mm by about 20 mm high. The shear strength of the consolidated mud was compared to that of competent, fresh spoil, a mixture of spoil and mud, and to completely degraded spoil (mud alone).These results have been used as inputs in stability calculations using the commercial computer program Slide 7.0, which demonstrates the strong influence of consolidation of the mud on overall low wall slope stability. The results provide insight into the design and construction of capping to isolate in-pit mud.CITATION:Vangsness, T A, Williams, D J, Islam, S, Smith, A and Bergin, L, 2018. Consolidation and shear strength testing and stability analysis of coal mine spoil degraded to mud, in Proceedings Mine Waste and Tailings Stewardship Conference 2018, pp 97–109 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 23, 2018

By J Westh, S Rashleigh, L Gallagher

Mining companies are moving towards automated haul trucks and other equipment. One reason for this is that if automated trucks can operate in a standard pattern over and over again without variation, then human error is reduced, if not eliminated.The challenge for mining production leaders/managers is to ensure operators follow standard operating procedures for load and dump operations, with each operator doing the same thing, every time. However, operators are only human and inconsistent performance is rife at every mine site. The finger may be pointed at the operators for not doing as instructed. The clarity and variability of trainer instructions may be considered causal to the problem. Herein lies the problem. Almost all operators believe they are following the procedure very closely; moreover, they all demonstrate a strong desire to conform to instruction.Using video analysis and feedback, each operator can be shown where and by how much they differ from the benchmark set by their company. Operators, often for the first time, can see definitively what they are doing, compared to industry best practice.The technology utilised by real-time video (RTV) crews measures time, distance and angles. It can overlay the video of the operator at the load site, with video of the perfect pass. Operators are amazed when they see how near to, or how far they are from best practice.The footage and data gathered by RTV assists operators in understanding exactly what adjustments are required to increase proficiency. It also assists load and dump superintendents to identify where in the process they are losing time. When translated to overburden removal or mineral/resource extraction, the result is large production economies without the need for large capital investment in new automated technology.CITATION:Westh, J, Gallagher, L and Rashleigh, S, 2012. Improving safety and mine productivity using real-time video technology, in Proceedings International Mine Management 2012, pp 173-188 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 20, 2012

By P G. Bourke, A Yáñez, G J. Jameson, N M. L Kupka

The kinetics of fine and ultrafine particles in conventional mechanical flotation cells are limited (Feng and Aldrich, 1999; Trahar, 1981; Wang et al, 2016). Accordingly, even limited recoveries with such machines require long residence times. Theoretical investigations into the rate of capture of fine particles by flotation, have indicated that a key parameter is the rate of shear in the fluid surrounding the bubbles and the particles. Achieving fast flotation rates of ultrafines requires a new method of bringing the particles and bubbles into contact, utilising the beneficial properties of highly dissipative flows to break through the water boundary layer. In 2010, a new type of flotation cell known as the Concorde Cell was described, in which bubbles and particles are brought together in a sonic shock wave (Jameson, 2010). Earlier research had shown that when a dispersion of fine bubbles in liquid passed through a converging nozzle at the local speed of sound, the resulting shock wave downstream generates a mass of even finer bubbles in the flow as it passes through the shock wave. The fluid within the shock wave is highly turbulent, and an environment is created that is very favourable to particle-bubble collision and capture. In this paper, we briefly describe the Concorde Flotation Cell and give examples of its use.

Aug 24, 2022

By Dunn P. G

The copper ore reserves at the Chuquicamata mine were re-estimated during March to June 1994, as part of a comprehensive audit of the mine's overall short- and long-term planning. The basic principles essential to all ore reserve estimates were implemented viz: 1. A detailed study of the geology, in this case particularly of the orientations of structural features of copper mineralisation and the subdivision of the orebody into geologically homogeneous sections, 2. the use of both drillhole and blasthole data sets, 3. statistical and geostatistical analyses of both data sets to model anisotropic spatial structures for all the geologically homogeneous sections, 4. block kriging using both data sets individually; and 5. a comprehensive validation of the block valuations to confirm the absence of global and conditional biases and to quantify the actual improvement achieved in the overall quality of the estimates compared to those executed on earlier techniques.

Jan 1, 1995

By N Yarahmadi

Characterization of pore pressure is critical for appropriate design of tailings dams. Furthermore, if seepage rates through tailing embankments increase unexpectedly or become uncontrolled, undesirable conditions may prevail to progress piping or internal erosion that could lead to the dam’s instability or ultimate failure. A three-dimensional seepage analysis was performed on a tailings dam using finite element method to find the rate of seepage and pore water conditions in the embankment and foundation. The results were then compared to a conventional two-dimensional seepage analysis carried out on the typical cross section of the embankment and the field data acquired from the instrumentation system. Considering the monitoring data, comparison of seepage analyses results for the two and threedimensional models, showed that the results of the conventional two-dimensional seepage analysis are significantly underestimating reality. Relying on two-dimensional seepage analyses might result in underestimation of seepage rates and impact the safe operation of tailings dams. Similarly, unrealistic prediction of pore water pressure conditions, based on simplified seepage analyses, can lead to overestimation of the rate of strength gain of material and consequently safe embankment raising rates.

Jul 1, 2021

During the period 1981 - 1991, Esso Australia and their Joint Venture partners have discovered about 180 MB of liquids (crude and condensate), 60 MB natural gas liquids and 800 - 1000 GCF of gas. A total of 48 wildcat wells were drilled including 12 new pool discoveries drilled from platform facilities. Significant discoveries include the West Tuna, Kipper, Blackback and Terakihi fields. These four discoveries, contribute to 75 per cent of the total reserves discovered in the last decade and were all high-risk plays. The Kipper discovery, in the pre-Latrobe Golden Beach Group top sealed by volcanics, and the Blackback-Terakihi discoveries, located on the present day continental slope in water depths ranging from 300-700 metres are both the result of successful drilling outside the traditional exploration bounds for the basin. During the last decade, Esso and its partners have spent about A$400M on wildcat exploration activity. The exploration success rate, excluding platform based drilling, has been 50 per cent for wildcat wells. On a technical front, the last decade has heralded substantial improvements in seismic data quality. Peak frequency content in seismic data at the Latrobe Group target levels is now double that of the early 1980s. Significant advances have also been made in our understanding of sequence stratigraphy, geochemistry and geohistory of the basin.

Jan 1, 1992

By M T. Nguyen, S Vink, M Ziemski

On any given mine site the water system is contingent upon its initial design. Through time the initial design is adjusted by a myriad of water management options in order to improve water system performance or to adapt to a new production capacity or method at the mine site. These options generally do not comprehensively consider energy requirements, so it is unlikely that any given mine water system will be optimised in terms of both water and energy uses. Thus this may simply shift constraints of efficiency of one resource dimension, water, to another, energy. As a result, changes in water systems would cause more energy-related issues to mining companies. For example, the companies would have an increase in operational cost and/or pay more for carbon tax with changes in their water system. Therefore, in order to avoid undesirable and potential unforseen energy and infrastructure issues in a mine life cycle, it is essential to select suitable water management options for a mine considering both water and energy resources simultaneously.Considering water and energy criteria in evaluating water management options consists of net water volume availability, net operational energy demand and net water replacement energy demand. Ideal water management options should be high in water volume availability but low in both operational energy demand and water replacement energy demand. A water option would also be favourable if it has low potential of causing adverse environmental impacts such as lowering groundwater tables due to groundwater withdrawal, or elevating saline constituents in surface waters when reusing brine for dust suppression. However, these environmental impacts are not considered in this analysis.This article presents a graphical method to assess mine water management options, based on these three criteria. The proposed method to assist in screening mine water management options includes two main steps:1. categorise water management options into prioritised groups2. rank the options within each prioritised group.The method is applied to a gold mine and presented in this article as a worked example. CITATION:Nguyen, M T, Vink, S and Ziemski, M, 2013. Selection of mine water management options considering both water and energy impacts, in Proceedings Water in Mining 2013 , pp 29-34 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 26, 2013

By Ward B

Central Colliery was developed to exploit large underground reserves in the German Creek lease. It was planned from the outset as a retreating longwall operation and is the first longwall mine in Queensland. Longwall mining is not new to Australia but all previous experience has been confined to the coalfields of New South Wales. There was no precedent for longwall extraction in the markedly different geological setting of the Bowen Basin in Central Queensland. Various investigations were thus carried out during the initial development of Central Colliery, prior to the installation of the longwall, to ascertain the geotechnical characteristics of the coal seam and the adjacent strata and to predict the performance of the heading and pillar design as mining proceeds to depth. Laboratory tests showed the coal to be weak with an unconfined compressive strength of 9.6 MN/m2. Site inspection and geophysical correlation revealed a shear zone and extensive intraformational shear planes in the seam. The latter were found to exert a controlling influence on rib reaction in the headings. This behaviour was predicted by finite element modelling of the development headings which indicated that mining induced stresses in the coal would be relieved by block movement of the ribs. A chain pillar width versus depth curve was established for yielding pillar design based on empirical and computational methods. This gave pillar widths from 25m to 48m over the proposed depth range of 150m to 300m. Finite element modelling of the 25m pillars chosen for the first gateroads confirmed the overall stability of the design but suggested that rib spall could be significant in the adjacent tailgate. (1) Chief Mining Engineer, Capricorn Coal Management Pty. Ltd., German Creek Mine, Queensland (2) Senior Engineering Geologist, Coal Division, The Shell Company of Australia Limited, Melbourne

Jan 1, 1986

By M Hino, Y Sasaki

Sustainable handling of municipal waste and sewage sludge has an important goal to recycle resources without supply of harmful substances to humans or the environment. The gasification mechanism of phosphorus from municipal waste and sewage sludge during the incineration process has been investigated to develop a phosphorus recovery system. Quadrupole mass spectrometer coupled to an electric furnace is applied to study the vaporisation behaviour of phosphorous gas phases from municipal solid waste (MSW) incinerator ash of sludge during solid-state reduction by carbon. Measurements are carried out in vacuum conditions of 2 x 10-6 Torrs and furnace temperature range 573 - 1773 K, at a heating rate of 7.22 K/minute. It has been found that most of the phosphorus is vaporised as PO2, P2 and P4, in agreement with thermodynamic estimation despite a shift in the temperature regimes.

Jan 1, 2006

By D Fukuda, K Kaneko, R Kudo, J Kodama, Y Fujii, T Sasaki

"Estimation of stress state as well as elastic modulus is important for the prediction of a rock slope deformation in an open pit mine since it can strongly influence the mining-induced deformation of the rock slope. This study applies a method to evaluate regional stress state and Young’s modulus by analysing the mining-induced deformation of ground. The effect of changes in regional strain state due to tectonic plate motion can be accounted for using the proposed method. Mining-induced deformation can manifest itself as changes in ground surface geometry resulting from mining activity. There are three underlying factors that can contribute to the deformation: displacement induced by the effect of gravity displacement induced by the effect of horizontal regional strain incremental change in the horizontal regional strain. The relative displacement arising from the mining excavation at the Torigatayama limestone mine in Japan has been measured by Global Positioning System (GPS). Both the regional stress state and Young’s modulus were estimated by back analysis of the change in distance between GPS stations using a 3D finite element method. It was shown that the reliability of the estimation improved with an increase in displacement due to mining progression. It was also shown that values for Poisson’s ratios of less than 0.10 are reasonable estimates with values for Young’s modulus between about 5?GPa and 10 GPa. The magnitude and direction of the maximum compressive stress in the district surrounding the Torigatayama mine were estimated to be between -6.4 MPa and -4.4 MPa and around N25E respectively.CITATION:Kodama, J, Sasaki, T, Fukuda, D, Kaneko, K, Fujii, Y and Kudo, R, 2014. Estimation of regional stress state and Young’s Modulus of ground at Torigatayama Limestone Mine in Japan, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference, pp 135–142 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 5, 2014

By W Patton

Investment decisions in the mineral resources sector are made on the basis of an assessment of the economic potential for a mineral deposit. Given the supporting information for the location, scale, and quantity of the commodity of interest, miners and investors aim to make risk-informed decisions when considering further investment. The objective of resource classification is the synthesis of various types and quantities of geologic information used in resource model construction to assign confidence categories to the estimated mineral resources, which can then be used to support informed economic decisions. In this paper a risk-based classification scheme for iron ore mineral resources using conditional simulations is presented. The method involves categorisation of each block according to a confidence level, considering expected recoveries from a kriging model over mining production volumes. The realisations of the simulated model are used to assign risk-based confidence categories to zones of the ore deposit. One motivation for this work is to assess the sensitivity of the scheme to geologic uncertainties. Specifically, that which uncertainty in the layout of mineralising alterations and weathering overprints influence variabilities of associated rock properties and the likelihood of obtaining expected ore recoveries. It is shown these risks have material implications for a project’s economic potential. How the scheme can be extended to the grade control context and the value subsequent grade control activities is also quantified.

May 24, 2023

By A Mehrani, F Zamani, A Dehghani

Vibrating screens play an important role in the dry classification circuit of Gol-e-Gohar iron ore processing plant. This circuit was designed to classify the autogenous mill discharge and produce a suitable feed, with K80 about 450 ¦m, for dry magnetic separators. Three parallel vibrating screens produce more than 50 per cent of the separatorÆs feed. The efficiency of the magnetic separator is greatly affected by feed size distribution. In this work, the JKSimMet 5.1 software was used as an analysing tool to assess the flow rates and USIM PAC3 software as the simulation tool to control and optimise the vibrating screens. Samples were collected and the circuit was mass balanced. Then the vibrating screen was simulated and adjustment parameters such as cut-point, bypass and imperfection factor were determined. The product streams of vibrating screens can also be predicted.

Jan 1, 2007

The Geograph is a revolutionary seismic system involving special techniques in combining the use of FIT magnetic tape with shock wave echoes created by a weight dropping system.The idea of- weight dropping as a- source of seismic energy is not a new,.,oxie. Records 'indicate òa pos'sihle use of falling weights as early as .1929. 'Dr. Burton McCollum began his experiments in 1938, but it wasn't until 1951 that the method was first proven useful.The first weight dropping crew began commercial operations in Edwards and Sutton .Counties of West Texas in 1953. By 1962, more than '40 weight drop-ping.crews have come into existence with operations in the United States, Canada, Algeria, Iraq, Argent na,òSpanish West Africa, Tunisia, Qatar, Niger Morocco and Libya by most major oil companies and larger independent oil companies. .

Jan 1, 1962

By Green A. D M

The establishment of the Imperial Smelting Furnace at Sulphide Coporation Pty. Limited for the smelting of zinc and lead made it necessary to design and install sintering capacity to produce approximately 500 t.p.d. of zinc-lead sinter. The updraught sintering process installed is a recent development and the plant was designed with adequate flexibility and equipment to enable operating staff to investigate the process and achieve maximum production under optimum operating conditions.Sulphur dioxide gases from the sinter machine are passed to a contact acid plant for the manufacture of sulphuric acid.

Jan 1, 1964

By B Nielsen, H Lehto, B Musuku

"The demand for fine and ultra-fine grinding associated with the processing of more challenging, finer grained orebodies and the global driver of minimising energy consumption has been an increased focus in our industry. Outotec’s stirred milling technology, the high intensity grinding mill (HIGmill™), was launched in 2012 in response to this industry need. First Quantum Minerals Ltd selected HIGmill™ technology for its Kevitsa mine in Northern Finland. The 700 kW mill is grinding copper rougher concentrate to improve copper/nickel separation and copper recovery. Selection of the HIGmill™ followed mineralogy analysis and laboratory and pilot testing for HIG milling in parallel with flotation tests to determine optimum grind size and energy input.The paper discusses the challenges and successes of the test work, manufacture, installation, commissioning and subsequent operation of the mill. Grinding performance is presented and a comparison between predicted and operating energy efficiency is made. In addition, the various steps to optimise wear rate and minimise maintenance and downtime are made, with particular reference to internal geometry of the mill.Citation:Nielsen, B, Lehto, H and Musuku, B, 2016. Design, Installation, Commissioning and Operation of Fine Grinding Technology at the Kevitsa Mine, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 59–66 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

By M Weeks

Melbourne Water Corporation, through the Pipelines Alliance, has commenced construction of a new drainage pipeline to provide additional flood protection within the Sandgate Avenue Main Drain catchment, in order to mitigate against the risk of flooding of Frankston’s central activity district (CAD).The project involves the construction of a 1550 m long, 2.5 m internal diameter tunnel, commencing upstream at the Monash University Peninsula Campus and traversing approximately west to the outlet located at Kananook Creek. The tunnel was excavated by a dual slurry-earth pressure balance tunnel boring machine (TBM), with the depth to tunnel crown ranging from 0.7 m to 14 m below the natural surface level. The TBM navigated 500 m radius curves, with a maximum drive length of 608 m. The tunnel lining consists of 2.5 m internal diameter, 250 mm thick reinforced concrete jacking pipe.The geotechnical conditions along the tunnel alignment consisted of mixed face ground conditions, predominately clay, with clayey sand and sandy clay and some sand deposits near Kananook Creek.This paper presents the challenges associated with the operation of the slurry separation plant during tunnel construction. In particular, the paper focuses the impact of slurry separation on tunnel advance rates, the lessons learnt during construction with regards to slurry separation and on the decision to adopt a dual slurry-earth pressure balance shield TBM. In addition this paper highlights the importance of having a thorough understanding of the slurry separation requirements on a slurry TBM project prior to selecting the necessary plant.

Mar 8, 2011

By Giles D, Wegmann D

The Mt Todd Gold Project is located 42 km northwest of the township of Katherine within the Northern Territory of Australia. It is situated in the southeastern portion of the Pine Creek Geosyncline. The Batman gold deposit, the largest of several deposits at Mt Todd, hosts an identified mineral resource of 92.9 million tonnes (Mt) grading 1.4 grams/tonne (g/t) as at 31 December 1993. Host rocks at Batman are assigned to the Early Proterozoic Burrell Creek Formation, comprising greywacke and siltstone interbedded with shale. Gold mineralisation is associated with a very broad zone of sheeted and stockwork quartz-sulphide veins that occupy a corridor of intense brittle fracture and faulting. A conceptual model of formation involves the dilation of joints and micro-faults within overlying sediments during sinistral movement along a basement shear zone. Synchronous granite intrusion generated convective circulation of crustal fluids through the sedimentary pile resulting in the formation of auriferous quartz veins within favourable structures. The Batman zone of mineralisation is not directly related to fold structures which typify several other major gold deposits within the Pine Creek Geosyncline.

Jan 1, 1994

By B Small

CSA Mine, named after the nationalities of the mines first owners being Cornish, Scottish, Australian, is one of Australia’s deepest and highest-grade copper mines. A combination of the modified Avoca method and shrinking was a standard practice where production rings were fired against and bogged to waste fill. This method resulted in dilution and involved rehandling of waste material to refill the bogged stopes in the Western region and the QTS Central. The introduction of pre-charging blastholes using a wireless initiating system (WebGen™) has enabled CSA to design and fire stopes in reverse. This involves the use of a pre-charged Temporary Rib Pillar (TRP) against the waste fill material in a previously mined stope. The temporary pillar reduces dilution and improves conventional bogging as material is blasted towards the drawpoint rather than towards the waste fill material. Additional drill, prep and blast re-work is reduced or completely removed as rings can be charged prior to, in conjunction with, or after, charging of the slot. This is a safer practice as the charge crew spend no time working adjacent to a brow or open void. A TRP trial was conducted in the western orebody at CSA. The risk of exposure to a brow or open void while charging underground, and the bogger rehandling of waste material was successfully eliminated. Once reverse stoping was established in modified avoca stopes at CSA, two TRPs were implemented in challenging ground conditions in the QTS Central region. The TRPs were utilised in a retreating four-way intersection to extract a central diminishing pillar to close the level out. The ore recovered in this stope provided 5 per cent of CSA’s copper for the year. Without pre-charging with a wireless initiating system, two 5 m pillars totalling 6936 t of ore at 7 per cent either side of the stope would not have been recovered. CSA has implemented the practice of reverse stoping in modified avoca stopes using TRP for ten stopes since the successful trial. The development of additional blasting techniques enabled by precharging with wireless initiating systems is currently underway in the QTS North orebody at CSA Mine.

Mar 29, 2023