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By D Reid, A Fourie, J Ayala

This paper discusses cone penetration test correlations for loose gold tailings that were developed within a critical state soil mechanics framework. The development of a new calibration chamber for cone penetration testing that consists of a modified triaxial cell is described. Some of the early development and commissioning issues that were encountered, as well as the solutions adopted are outlined, including the system to prepare the samples and to acquire high-quality data from the testing. Also, the triaxial laboratory testing required to achieve the critical state line is described, including some of the basic precautions considered necessary as good practice. Additionally, the system adopted for volume tracking of the calibration chamber sample is described, which is essential for ensuring a reliable state parameter comparison against the acquired cone penetration test data. Finally, some laboratory test data from the calibration chamber is plotted against the soil behaviour type charts currently available from various authors.

Jul 1, 2021

By S Brochot

During the development of a mining project, samples are taken for metallurgical tests. The sample can be a composite sample made of material coming from a selection of various drilling products or a sample coming from a mining test. This sample can represent several tonnes of material which are analysed and split to be used in various tests.In the current case, a composite sample is dedicated to semi-autogenous grinding (SAG) pilot plant tests. The property of interest is then the size distribution of the material. The sample is mixed and a subsample is taken to measure the size distribution which is considered as the feed size distribution. Then the remaining material of the sample is divided in several subsamples for batch grinding tests at different operating conditions. The product of each grinding test is then analysed to measure its size distribution.The grinding performances are analysed at the light of the measured size distributions for feed and product. But what is the accuracy of the measurement of these size distributions? What is the variability of the feed knowing each feed is just a subsample of the initial sample?The Pierre Gy theory of sampling answers these questions.The current paper presents, through a real example, the calculation of the measurement error of the size distributions and the variability of the feed between the different tests. The uncertainties of the grinding performances are then calculated and their impact on the results interpretation is then analysed.CITATION:Brochot, S, 2012. Sampling for grinding pilot plant test - the effect of size distribution variability, in Proceedings Sampling 2012 , pp 127-134 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 21, 2012

Techno-Economic Evaluation of a New Early Removal Process to Treat High-Arsenic Copper Ores

Sep 13, 2010

By R Varden

This paper summarises the process taken to simplify 35 ground support standards accounting for the multiple development profiles, dynamic geotechnical environment and the practical safety implications of a large-scale change in the ground control standards. This reduction was required after an incident involving incorrect standards being issued. The subsequent investigation identified that: • Selection of ground support standard for a mining instruction (MI) is not straightforward due to multiple standards, standards not reflecting current reinforcement used and complex geotechnical environment being encountered. Instead, site-specific ground control instructions were being issued. • Ground support standards were hard to follow and confusing, errors were present and not all standards to scale. • Ground support standards being used did not reflect what was being installed, ie bolt type incorrect and mesh orientation different. • No process or tier action response plan (TARP) for operators to follow for ground control standard noncompliance. • No justification for ground support standards being used in the current geotechnical environment. • No process for ground support standard selection and thereby no paper trail to document and assess adequacy of performance. A project was undertaken to reduce and simplify the ground support standards, produce a justification document to support ground support design and develop a process for site practitioners to identify the type of ground support standard required for the mining instruction. The exercise of rationalising the ground support was met with some challenges, including: • Technical aspects to determine the level of demand and the capacity for each ground support scheme. • Training the geotechnical engineers how to determine the level of risk for each area. • Winning over other technical services staff and the underground mining contractor of the new approach and then implementation. One of the major successes was the acceptance by the underground operators who found the system simplified their work and gave them increased confidence in management of seismicity. The rationalised ground support standards have now been successfully in place for over two years.

Mar 29, 2023

By S R. Green, G D. Corder

The legacy issues from mining can, and have often, extended well beyond the closure of operations. However, conventional cost-benefit analysis provides little incentive to implement initiatives at the project development stages of a new mining project as the costs that will be incurred towards the end of the mine life, 20 years or longer, appear minor in net present value (NPV) terms. This analysis can be misleading as the true costs of managing post-mining land can continue for many years, or decades, after mining ceases and any resulting unfavourable legacy issues can delay or prevent government permits or licences to develop new resources. Proper upfront planning is critical for implementing successful rehabilitation and closure strategies. The investment in this planning needs to be done in a structured and rigorous manner taking into consideration the long-term and broad benefits of sustainable land uses after mine closure. The advantages of such an approach could include the streamlining of regulatory approvals by early advice to the regulator of identified issues and responses to those issues, and clear evidence that a strong social licence to operate ethic with local, regional and national benefits is included in the decision-making process. This paper investigates the potential closure options for two case studies at the early stages of project development - concept and prefeasibility. By using a sustainability framework that can identify opportunities and risks, prospective initiatives that deliver enhanced environmental, community and social benefits will be compared with compliance-orientated approaches. This comparison is made across the Five Capitals Sustainability Model - natural, human, social, manufactured and financial. The results of this analysis demonstrate that upfront planning during project development and due care and effort during the life of the working mine will reduce the risks of long-term detrimental legacy issues. This will ultimately benefit the mine operator, the local community and the state.CITATION:Corder, G D and Green, S R, 2012. Using a sustainability assessment framework to achieve enhanced legacy outcomes, in Proceedings Life-of-Mine 2012 , pp 311-318 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 10, 2012

By Fejes G

An integral part of the Brisbane Suburban Railway Electrification involved the relining, refurbishment and track lowering in the Roma Street, Brunswick Street and Gloucester Street double track tunnels. The design and the construction procedures had to satisfy the Queensland Railways electrification clearance and track standards and the requirements of maintaining track services through the tunnels during work. Refurbishing of the tunnel linings was carried out to extend the life of the tunnels.

Jan 1, 1981

Platinum Group metals have been known in New Zealand since the 1880's but not produced on a large scale. They have been neglected because their value was not appreciated rela- tive to gold and their value was often very low, reflecting demand, and because recovery was difficult compared with recovery of gold. With the rising price of most Platinum Group metals and the perfection of gravity and flota- tion recovery methods, recovery of platinum along with gold from alluvial deposits is more attractive. Platinum Group metals are known in several different environments in New Zealand, ranging from alluvial placer deposits to layered basic to ultrabasic intrusions and quartz veins. None of the known occurrences have been ade- quately prospected and there is a real possibi- lity of future discovery of important deposits. Several New Zealand based and at least two offshore resource companies are currently involved in exploration, prospecting or mining for Platinum Group metals in New Zealand.

Jan 1, 1987

By A G. L Pratt

Inclined troughed belt conveyors are more frequently being selected from a range of alternatives, which include shafts and trucks for ore haulage in underground mass mining projects. Belt conveyor haulage systems are being operated with lifts exceeding those normally associated with truck haulage systems and approaching the limits of shaft haulage systems. A belt conveyor haulage system, in this context, incorporates subsystems for: crushing,tramp detection and removal, andhaulage. This paper presents details of recent inclined troughed belt conveyor systems for underground mining operations, and explores the application of inclined troughed belt conveyors for the increasing demands of future underground mass mining projects.

Jan 1, 2008

At Pasminco Mining's South concentrator. which was commissioned in 1952. an expansion. modernisation and efficiency improvement program commenced in 1986 with a coarse ore stockpile and grinding circuit expansion. the replacement of small flotation cells and the upgrading of reagent mixing and metering equipment. The program continued with the installation of a TDC 3000 based process control system (1988) and concentrate thickeners (1990). By mid-1991 a further grinding expansion and the installation of zinc flotation feed regrind ball mills and zinc recleaner column cells will be complete. leaving the use of ceramic disc fillers and development of process control strategies as probably the remaining major avenues for improved process efficiency at present.

Jan 1, 1991

Until early-1997, Mount Isa Mines Limited (MIM) generated electrical power for most of north-west Queensland. The discoveries of many new orebodies in the region meant the inevitable increase in power generation requirements for the new mines. In addition, the expansion at Mount Isa itself meant that MIM had to invest in new generating capacity or utilise the existing generating plant more effectively. Using its generating plant more effectively required MIM to undertake rigorous energy management within its own operations. A personal computer based system with a wide area network was installed as the basis for energy management. The result was that energy consumption was reduced, the need for additional generating plant was curtailed, and capital outlay for the generating plant that was required was delayed. As a direct result of energy management, carbon dioxide emissions were reduced substantially.

Jan 1, 1998

The karst water system in Han-Xing District is charaterised by heterogeneity in karstification and permeability of the limestone aquifer, unsteady flowing of the groundwater along karst runoff zone system, periodic recharge related with the periodic precipitation, and concentrative discharge of the groundwater in the form of karstic spring groups. The basic law is that the quantity of the water is very large during waterflood period and rather small in dry period, which has brought about difficulties and contradictions in mining and water supply. The measure to bring the karst water under control must be based on the principle of comprehensive ways and on the systems engineering method. Macroscopiclly, it is the reasonable countermeasure to retain surface water in the upstream section of the karst water system and to strengthen infiltration in the midstream section and to combine exploitation and utilization of the groundwater with water protection and mine dewatering in the area in which mines are distributed.

Jan 1, 1988

The T33-34 blast, the first major blast at Mount Isa Mines, broke 1,360,000 tonnes of copper ore using 349 tonnes of explosives. The original concept of firing T33, T34, T35 and U37 separately was changed during the life of the project due to adverse ground conditions. These conditions also caused the stoping method to be modified after the firing of the stopes had started. To stabilise the two stopes T33 and T34 where large fall off was occurring, rib pillars were left in the original slot. This caused the blast design to be more complex as these rib pillars had to "lead" the blast. The implication of such a large blast on the underground and surface environment was thoroughly investigated and precautions taken. The charging time of the blast was six weeks. Hook-up was started four days before the blast and continued until two hours prior to the blast. Detailed scheduling was carried out of other work that had to be done in the 24 hours before the blast to ensure that there were no delays in the firing.

Jan 1, 1977

By M Lak, R Amiri, A Haratian, M Asghari, S Haji

Dry magnet separators are used to upgrade and beneficiate a wide variety of minerals such as hematite and magnetite materials. In recent years advances in dry magnetic separators have improved their performance. Fine particle separation is one of the main areas which still remain weak. This paper will present a new design of fine particle drum separators which used for particle size less than 3 mm. A big problem in processing of iron ore is the grade and recovery of mineral values in the fines fraction. The new design high efficiency drum separator is developed to handle fine feeds. In this drum separators both of the drum shell and magnetic yoke rotate in opposite direction. the results showed that when the material feed size was = 1298 μm, drum shell speed was 42.5 rev/min, magnetic yoke speed was 100 rev/min and the maximum intensity of magnetic field was at = 30° the feed grade increased from 50.87 to 65.67 in concentrate box, increase to 60.45 in middle box and tail grade was 24.44. The total achieved recovery for both concentrate and middle box was 81.89 per cent.

Nov 8, 2021

By J M. Menacho, L Zhang, A Hoadley, L Verdugo, B Etschmann, W Bruckard

Since the introduction of Lithium-Ion Batteries (LIBs) in 1991, the market for lithium-ion cells has been driven by the high demand for portable electronic devices and more recently for batteries for the electric car industry. It is expected to grow rapidly to reach 2600 GWh globally by 2030 (US Government, Office of Energy Efficiency and Renewable Energy, 2021). However, there is a desperate need to recycle LIBs to recover valuable cathode materials and graphite. For this reason, several physical and chemical recycling technologies have been proposed to recover these materials from spent batteries. Amongst these, froth flotation technology is a potential cost-effective technology for separation of the graphite fraction from the lithium oxide components due to the natural hydrophobicity of graphite and density difference between graphite and cathode materials (Folayan et al, 2021).

Aug 24, 2022

Kambalda Nickel Mines (KNM) currently have eight operating underground mines, three on care and maintenance and other orebodies at various stages of development. Each operation differs greatly in scale, ore grade, milling characteristics and cost structure. The optimum number of mines operating at any one time and their level of production, within the constraints of mill blending requirements and overall mill capacity, is the key to maximising profit in a climate of fluctuating nickel price. Cost models are developed for each mining operation which relate ore tonnes mined to total cost per pound of nickel produced from that mine. Aggregating the mine cost models provides a composite cost model for the entire operation. The cost models provide the operating levels necessary for each of the mines and hence Kambalda as a whole, to operate at the lowest cost per pound of nickel produced. However, lowest operating cost does not necessarily lead to maximum profit. The level of nickel price above operating cost can dictate maximum profit positions which are contrary to the lowest cost position. In addition, the decision to temporarily shutdown mines or reopen mines in response to nickel price movements comes at a cost. In considering the optimum operating position, the price of production capacity flexibility needs to be taken into account. This paper describes the process used to assess all these factors in arriving at the optimum operating position for Kambalda Nickel Mines for varying nickel prices. The same methodology can be used by corporate management in managing multiple mine sites as well as mine management managing multiple orebodies or stoping blocks for maximum profit.

Jan 1, 1995

By G Harbort, D Clarke, D Morgan, C Sola

Northparkes Mines commenced production in 1994 and the mine has significant reserves to allow operation into the future. There are a number of potential future concentrator feed sources with variable sulfide mineralogy and grades.In February 2012 a comprehensive flotation survey was conducted to allow mass balancing and evaluate the operation of the flotation circuit. A rudimentary, copper element only, unsized flotation simulator was developed to evaluate high level potential for optimisation and improvement. In 2013 this flotation model was expanded to produce a mineral based, floatability component model to estimate the effect of future concentrator feed source on metallurgical performance. This revised model allows various circuit configurations to be simulated to provide a high level blueprint for the long-term planning to maximise performance.This paper provides a review of the process followed to develop the model, including an analysis into the mineral floatability component model and its calibration against plant operations. The effect of varying feed mineralogy and feed quality on future performance has allowed an internal review of potential circuit changes needed to accommodate the changing future feed.CITATION:Clarke, D, Harbort, G, Morgan, D and Sola, C, 2014. Northparkes Mines – flotation and planning for the future, in Proceedings 12th AusIMM Mill Operators’ Conference 2014 , pp 203–208 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 1, 2014

By M Manefield, G Bournival, S Ata

Asteroids contain an abundance of valuable resources such as: nickel, cobalt, gold, platinum and rhodium. Whilst the consumption of mineral resources on Earth continues to deplete, meteoroids have the potential to become a significant source of minerals. Even though the minerals content of asteroids may be relatively high, the valuable minerals are more likely to be only a small portion of the total ore present in the main body. The ores must, therefore, be processed to extract the metals of interest from the waste. Existing terrestrial technologies rely on manipulating the physical and chemical properties of minerals. The application of these techniques to asteroids processing, however, is not straightforward due to the presence of different conditions such as zero gravity and lack of water in space. This paper discusses potential separation and extraction techniques that can be used for processing of asteroids.CITATION:Ata, S, Bournival, G and Manefield, M, 2015. Resource recovery in space, in Proceedings Third International Future Mining Conference, pp 275–280 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 4, 2015

By Riley S. J

Ranger Uranium Mine is located within the Alligator Rivers Region of the Northern Territory of Australia and surrounded by the World Heritage listed Kakadu National Park (Figure 1). The mining operation is currently producing about 1500 tonnes of uranium oxide annually, as well as considerable volumes of waste rock, low grade ore and tailings. The rehabilitation of the project should ensure that the radioactive mill tailings and other contaminants remain contained for at least 200 years, as required by the existing guidelines (Commonwealth of Australia, 1987). The present uranium mining operation is regulated by the Northern Territory Department of Mines and Energy who must refer to the Environmental Requirements when considering regulatory options. These Environmental Requirements were agreed by the

Jan 1, 1994

This paper provides a brief fundamental insight regarding the fabric media concept for liquor filtration. The subject matter will be of interest to metallurgists and engineers with professional responsibility for world class design of solid liquid separation processes and efficient lowest cost operation of existing mineral process plant. Avocet Mining commissioned the worldÆs first mineral liquor clarification process incorporating a fabric media liquor filter at their Lanut gold mine in Sulawesi, in 2004 with design consulting provided by the Australian company SLS Technology Pty Ltd. Development of the technology continues with applied research focused on selecting textile parameters to apply filtration to a wider range of particle and contaminant types, higher solids concentrations, and different process liquors. Liquor filtration with the Fabric Media technology offers an array of attractive benefits. For Avocet Mining, filtration of pregnant liquor directly from the heap leach pad has enabled removal of the sediment pond and sand filters from the traditional process flow sheet, thus providing significant cost and installation time savings. Avocet Mining has recently expressed confidence in the technology indicating selection preference of the technology for the expansion at Lanut and for a new project. The application design window for the Fabric Media concept is extremely flexible with the technology now successfully applied to many different liquor chemistries and application objectives around the world. Potential cost savings for solid liquid separation process plant, such as counter current decantation circuits, clarifier vessels and thickener tanks can be calculated from laboratory measurements or pilot plant demonstrations.

Jan 1, 2008

By D J. Brake

The risk from fire remains one of the most serious of underground mine disaster scenarios. The impacts of mine fires on the underground ventilation system and the production of toxic gases have been difficult to model and therefore assessments have relied largely on empirical data, historical precedent and subjective opinions. Underground fire modelling software has had limited availability and been technically challenging and time consuming to use especially for routine mine investigations. There has also been no well-accepted set of assumptions for fire modelling in mines, which has resulted in a lack of confidence in adopting its use more widely. This paper describes modelling of three critical fire scenarios in underground hard rock mines: a fire (LHD) in an underground diesel refuelling facility, a fire in an underground explosives magazine and a fire on an underground ore transport conveyor. Modelling was undertaken using VentsimÆs VentFIREÖ fire simulation module. It describes the basis of design, the key assumptions, the methodology used and provides examples of the outputs, conclusions and recommendations. It reviews the impacts of these fires on egress and entrapment strategies in the mine. Some general principles regarding improvements to ventilation circuit design based on this analysis are also recommended. Whilst the fire scenarios were based on actual case studies, they have been disguised for this paper.CITATION:Brake, D J, 2013. Fire modelling in underground mines using Ventsim Visual VentFIRE software, in Proceedings The Australian Mine Ventilation Conference , pp 265-276 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 1, 2013