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"Cash flow modelling during project evaluation is enhanced when probabilistic methods are applied to the inputs. One of the important inputs is the quarterly production profile. Typically, the steady-state production profile provided to project evaluation practitioners is deterministic, with each quarter the same as every other quarter. This is unrealistic as actual production profiles from existing mines exhibit a range or quarter-on-quarter variance. Monte Carlo stochastic simulation of the production profile can be used to provide a range of possible outcomes, but how are these ranges selected? This paper describes the use of quarterly production variance from a large database of mines worldwide as a benchmark to inform the appropriate selection of ranges. The coefficient of variation is used to rank the production from mines, with quartile analysis applied to indicate industry best, median and worst variation. Due diligence of existing mines and evaluation of future production performance can be quantitatively assessed using this approach. Examples of the effect on value are provided.CITATION:Stewart, C A, 2016. Production variance benchmarks and their use in project evaluation and due diligence, in Proceedings Project Evaluation 2016, pp 201–213 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 8, 2016

By B Laidens, D Souza, W Bielefeldt

The CaO-MgO-SiO2-Al2O3 system, characterised by its intricate phases and thermodynamic properties, plays a pivotal role in steel secondary refining processes, encompassing desulfurisation, non-metallic inclusion capture, and refractory protection. Accurate predictions for diverse industrial applications, including metallurgy, ceramics, and materials science, are imperative. To address this challenge, a combination of machine learning techniques will be specifically applied to model the liquid fraction of the slag and the solid fraction of MgO. The development of an artificial intelligence (AI) system, leveraging various machine learning techniques, has gained momentum in this project. The focus of this work is on constructing an AI model, based on machine learning techniques, within the CaO-MgO-SiO2-Al2O3 system, utilising simulation results from FactSage™, version 8.1 (by GTT Technologies). The primary objective is to train the AI model using these simulation outputs to predict the percentage of liquid fraction and MgO saturation based on chemical composition parameters. The AI model will undergo training with a comprehensive data set of simulations within the CaOMgO- SiO2-Al2O3 system, covering a diverse range of compositional at 1873 K. These simulations, conducted through FactSage™ 8.1 software, provide a robust foundation for AI model training, ensuring generalisability and precise predictions for the liquid fraction of the slag and the solid fraction of MgO, the solid fraction of MgO in this case is determined by the difference between the total MgO and the MgO in the liquid fraction, so it is not the objective of this study to determine which phase of MgO is in the solid state.. The predictive capabilities of this AI model hold significant implications for process optimisation, quality control, and decision-making in CaO-MgO-SiO2-Al2O3- dependent industries. Precise estimations of the liquid fraction and MgO saturation empower researchers and engineers to enhance operational efficiency and quality. This paper explores the methodologies employed for AI model creation and training, achieved results in terms of prediction accuracy, and potential applications in the field. The development of this AI system signifies a notable advancement in utilising machine learning for better comprehension and control of complex chemical systems. Furthermore, to align the study with real-world steel production, we introduce FeO and MnO at concentrations of 2 per cent and 1 per cent at 1873 K, respectively, following the validation of model results using the CaO-MgO-SiO2-Al2O3 system. This adjustment aims to bring the study closer to the observed reality in steel mills globally.

Jun 19, 2024

By J Jasper, L Koroznikova, J Begelhole

This paper outlines a comparison of heavy liquid and heavy suspension separation methods for iron ore characterisation.As part of Arrium MiningÆs program to improve its knowledge of ore types being processed in its two hematite ore beneficiation plants (OBP), metallurgical evaluation of hematite feed for the upgrading process has become a major focus.Iron ore deposits almost always contain more than one valuable (and relatively dense) iron mineral. Iron ores are found with a range of iron contents, giving rise to density variations.At present the industry relies on heavy liquid separation techniques for the evaluation of iron ore samples arising from exploration, mining or metallurgical processes. There are only a few high-density liquids available, which are both high-cost and highly toxic.Low-toxicity solutions that can be utilised at relative densities up to 3.0 have been developed. However, highly-toxic organic liquids are required presently to achieve relative densities beyond 3.0.Bromoform which has a specific gravity (SG) of 2.89, and diiodomethane (SG 3.31) are commonly used; both present significant health and safety hazards.æClericiÆs solutionÆ (mixtures of thallium formate and thallium malonate) provide liquids having specific gravities between 4.0 and 5.0. ClericiÆs solution is highly toxic and testing is currently conducted by a limited number of laboratories worldwide.An alternative to ClericiÆs solution and organic liquids is a low-toxicity, high-SG, suspension technique, which has been demonstrated successfully for heavy mineral sands. This heavy suspension method employs mixtures of fine tungsten carbide particles in lithium heteropolytungstate (LST) solutions.Heavy liquid separation is not commonly used as part of routine iron ore feed characterisation due to the expensive, toxic and time consuming nature of the technique. Our results show that the heavy suspensions method can achieve low-cost, low-toxic separation and are outlined and results compared with results using ClericiÆs solution presented.Heavy suspension technique provides a theoretical/absolute separation of a particular sample. By placing an iron ore sample in a suspension of a particular density, it produces two products: a sink fraction and a float fraction. As iron oxides-hydroxyoxides are denser than the gangue minerals associated with the ore, particles that have high iron content will sink and the particles with gangue association will float. This process is repeated over several densities, thus also enabling separation of the constituent iron ore phases. A theoretical grade and a theoretical mass recovery can be calculated. With these calculations, a grade-mass recovery curve can be constructed for any element that is of interest.This type of characterisation can be used to either prepare OBP feed-piles of known processing characteristics, or to benchmark the performance of the process against what can be theoretically achieved on a continuous basis.CITATION:Begelhole, J, Jasper, J and Koroznikova, L, 2013. Application of the heavy suspension technique for ore beneficiation plant feed characterisation from the Southern Middleback Ranges, in Proceedings The Second AusIMM International Geometallurgy Conference (GeoMet) 2013 , pp 269-278 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 29, 2013

By B Shi, Y Li, L Ma, F Zhou

Subsurface fires are a common threat to coal mining, as spontaneous combustion of coal can potentially result in gas combustion and explosion. Fire-proof techniques, such as grouting, foam, or colloid injection, are not in a position to function ideally, due to the limited coverage and stopping the extinguishment substance from reaching the fire location. Liquid nitrogen, as a kind of all-submerged fire prevention or extinguishing method, can rapidly extinguish fires, thus preventing gas explosion and minimising extinguishment time. Injecting liquid nitrogen through boreholes is an important way during the period of mine catastrophe. But liquid nitrogen is not effective enough in infusion; technical issues restrict the development and utilisation of liquid nitrogen fire prevention and extinguishing technology. Immediate infusion of liquid nitrogen is usually associated with ‘air slug’ (the balloons and bubbles in the pipeline which hinder the flow of low-temperature liquid), which blocks pipelines for liquid nitrogen injecting. Another issue is that the pipeline tends to be damaged due to freezing, which undermines the injecting efficiency of liquid nitrogen and its application result. In order to solve the problems of the low efficiency and some other related field issues in liquid nitrogen perfusion, the ground–underground high efficiency liquid nitrogen injection technology were developed. Implementation of liquid nitrogen infusion techniques in Chinese coalmines achieved the goals of fire prevention and air-cooling. The technique presented in this paper is efficient in absorbing heat, and consequently, displacing oxygen and combustible gases. Field tests at Rujigou and Yangchangwan Coalmine justified the efficiency of the technique. By using this technique, there was no waste left behind, which may impede the subsequent production. The presented technique is of great benefit to the social, economic, and environmental aspects of mining operations, and will have broad applications in fire prevention for large-scale coalmines.CITATION:Zhou, F, Shi, B, Li, Y and Ma, L, 2015. Key techniques and engineering applications of stereoscopic liquid nitrogen infusion for coalmine fire prevention, in Proceedings The Australian Mine Ventilation Conference, pp 291–298 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 31, 2015

By C N. Hatton, K Ward

Tailings operations are inherently reactive as operations personnel continuously contend with a concentrator reject feed (tailings) transient in physical and engineering properties, which places a constant constraint on capital and operational spending. It requires a unique skill set to manage the prescribed distribution of tailings under unenviable conditions. Enter the tailings operator, an oftenundervalued commodity and untapped resource that can provide benefits beyond the rigors of dayto- day operational support. Experience consistently demonstrates that skilled and committed operators can serve a vital function in the safe construction of a tailings storage facility. It takes a village to raise a tailings dam. An important part of this process is establishing a culture of operational accountability and ownership. Operator development training is nothing new. However, we find that many of the intrinsic operator skills are left unexploited, and an operator's experiential knowledge base and creativity are commonly overlooked and underutilized. With proper training and guidance, these skills can be harnessed, contributing to safe dam operations. Operator engagement, when properly facilitated, provides tangible benefits ranging from improved tailings engineering properties to reduced closure costs. One important benefit is helping transitioning tailings management from reactive to proactive. There are many processes involved in the reactive to proactive transition process. One element of that process includes engaging operators in the tailings management process and facilitating legacy ownership. The core of operational legacy ownership is measured and described using five-stage operator engagement rubrics. Levels of operator engagement are presented with a description of the incremental benefits of each stage. An important part of legacy engagement is providing the tools to operators necessary for managing the tailings. Therefore, the approach identifies specific methods used by operations personnel to control tailings distribution and in-place properties. The end goal of leveraging operator engagement is to facilitate committed ownership and transition tailings management from an inefficient, reactive process to an improved, cost-effective, proactive practice.

Jul 1, 2021

By C A. Cooper, G A. Suter

The sizing of a starter dam for a Tailings Storage Facility (TSF) involves balancing many competing demands. It should cost as little as possible, be high enough to store tailings until the first raise can be constructed, it must be able to contain water safely, and it must be designed in such a way that the long-term integrity of the higher raises are not compromised, among other things. In addition to these demands there is the complication of the behaviour of the process plant, and the tailings during commissioning. Variations in slurry density, excess water in the TSF, initial settled density of the tailings, reliability issues, and beach slopes above and below water can all impact the way the tailings beaches are developed and ultimately impact the ability of the starter dyke to contain the required volume of tailings and water.The conventional approach to the design of a TSF starter dyke is to begin looking at the elevation required for a set of deterministic design parameters, find ways to reduce the size or volume of it as much as possible to reduce cost, and then possibly look at the sensitivity of some of the input parameters. This paper discusses a stochastic modelling approach for starter dykes that allows a wide range of design inputs to be simulated quickly, with an envelope of possible results produced. The sensitivity to different parameters can also be examined to understand which design inputs have the biggest impact on the required dyke sizing. By integrating the 3D TSF modelling tool Muk3D with GoldSim, it will be demonstrated how a wide range of scenarios can be evaluated and how that information can be used to make better decisions about the selection of design options.CITATION:Cooper, C A and Suter, G A, 2018. Starter dyke optimisation with Muk3D and GoldSim, in Proceedings Mine Waste and Tailings Stewardship Conference 2018, pp 466–475 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 23, 2018

By R Bertuzzi

Permanent rock bolts in civil engineering are taken as having to serve their design purpose for at least 50 years. In many projects the design life is specified as greater than 100 years. A review of recent Australian tunnelling projects shows that substantial differences exist in the level of corrosion protection provided for permanent steel shafted rock bolts. This paper reviews the current state of practice and sets out what the authors consider to be appropriate requirements for corrosion protection.

Jan 1, 1999

By G Simpson, S Dressler, A E. Levett

Tailings storage facilities often represent a mining operation’s most significant liability, posing serious environmental, social and safety risks. Almost all mining operations dispose of wet tailings (Valenta et al, 2023), which represents a risk of failure due to the potential for a rapid strength reduction of the unconsolidated materials leading to static liquefaction and subsequent dam wall failure. As a waste stream, tailings disposal, decommissioning and relinquishment aim to be inexpensive processes, ruling out many highly engineered solutions. Advantageously, tailings consolidation does not need to be immediate, opening the door for relatively passive, inexpensive consolidation methods that aim to gradually increase the strength of tailings over extended periods (ie years). In this paper, we present the prospect of novel in situ tailings stabilisation, learning from studies that have investigated the most erosion-resistant landforms on Earth.

Aug 2, 2023

By G McCullough, B Mutsaers, J Jessop

"*This is an abstract only* Geometallurgical initiatives have demonstrated considerable value to operations that have trialled them. However, it is extremely difficult for these initiatives to become properly embedded into the operations and for that value to be realised on an ongoing basis.This paper will explore some of the historical reasons why this is the case. Some of these reasons include the limited tools available to manage an integrated operation. These, in turn, have resulted from poor communications infrastructure, inadequate sensor capability and the way technical mining software has evolved over the last 30 years.This paper will then investigate how the evolution of technology in recent years can help overcome these constraints and compare progress with similar industries.CITATION:McCullough, G, Mutsaers, B and Jessop, J, 2013. Obstacles to embedding geometallurgy decision-making into operations and how to increase maturity of this critical capability, in Proceedings The Second AusIMM International Geometallurgy Conference (GeoMet) 2013, pp 139-140 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Sep 29, 2013

By M Bellamy

The DeGrussa copper deposit was discovered by Sandfire Resources in April 2009. Construction of the 1.6 Mt/a concentrator, open pit and underground mining operations commenced in March 2011 with first concentrate production achieved in October 2012. Over the next ten years, DeGrussa grew to include both the DeGrussa and Monty underground mines, establishing itself as one of the world’s premier copper producers with total production of 663 000 t of contained copper by the time the mine closed. Final ore was trucked from Degrussa on 5 October 2022. This paper examines the mine closure experience from both a planning and operational perspective. The paper provides an overview of the site’s mine planning process including the factors involved in determining the end of the mine life and how this was tracked and communicated in the lead up to the end of mining operations. It will also look at some of the specific operational aspects involved in maintaining steady state production all the way through to the last day while facing increasingly challenging conditions. These factors, along with the external factors faced by most of the industry such as labour shortages and COVID related disruptions, contributed to making it an interesting journey to the end of operations at DeGrussa.

Mar 29, 2023

By G P. S Resende, D E. G Oliveira, E A. S Baeta, T F. Bravin

There is currently in the mining industry, as well as in other industries, a movement seeking to increase investments in decarbonisation processes to help combat global warming. Among some initiatives taken is replacing diesel-powered mobile equipment in the mines with electricity-powered equipment, such as electric off-highway trucks or even belt conveyors in the mining operation. Samarco is a Brazilian mining company that since its conception has used a conveyor belt mining system in its mining operation, using only a small number of trucks to complement the mining process. This mining process that combines conveyor belts and trucks has brought environmental gains for the company since the environmental impact of conventional truck-only mining is greater than that of the combined system. To measure these gains, a medium-term mining plan was developed in which two fleet scenarios were detailed. One scenario contemplated a high level of detail of belt mining seeking its maximisation, while the other considered the operation performed 100 per cent by trucks, eliminating the use of conveyor belts. Through the comparison of these two scenarios, it was possible to make an inventory of atmospheric emissions and greenhouse gases for each one of them considering data such as types of equipment, diesel consumption, total distance travelled and energy consumption. The results showed that the fleet scenario with conveyor belts results in periods with up to 15 per cent less greenhouse gas emissions and 37 per cent less total particulates compared with the truck-only scenario. Therefore, the results confirm the environmental benefits of the method and the need to look for ways to even expand it in future operations through a study to identify the potential areas in the long-term mining plan.

Sep 18, 2023

By Z Terzic, M Schult, D Chu, S Macklin

The East West Link road tunnels are proposed to provide a connection between the CityLink toll road and the Eastern Freeway north of the Melbourne CBD. The alignment passes from Moonee Ponds valley beneath the Upfield Line railway cutting, Royal Park, the historic Melbourne Cemetery and beneath Alexander Parade rising to an eastern portal at Hoddle Street. The western (Royal Park) part of the alignment passes through the folded and faulted Silurian Melbourne Formation, which has been subjected to deep weathering since the Triassic.The Melbourne Formation in the Royal Park area is mainly characterised by interbedded sequences of siltstone and fine-grained sandstone. The beds are often graded and a clear boundary between the siltstone and fine-grained sandstone rock can be difficult to distinguish. Variation in lithology and the presence of structural geological features such as folds and faults have resulted in an irregular weathering profile within the Silurian rock; nonetheless the formation typically becomes less weathered with depth.Due to difficulties in obtaining reliable laboratory strength and stiffness relationships with weathering grade, in situ testing methods such as downhole shear wave velocity and high-quality pressuremeter testing are a useful aid to assessing appropriate geotechnical parameters for design.This paper presents an analysis of the variation in shear modulus of the Melbourne Formation, determined at small-strain (from downhole seismic data) and at ‘engineering scale’ strain (from pressuremeter tests) for extremely weathered (XW), highly weathered (HW) and moderately weathered (MW) rock. Estimates of small strain shear modulus (Go) obtained a range between 400 to 3400 MPa for these weathering grades. By comparison against the pressuremeter test data, reduction factors to be applied to these Go values to estimate shear moduli at engineering strain levels typically range between 0.10 and 0.35.The downhole geophysics undertaken in the Royal Park boreholes also suggests that there is an inversion in velocity between approximately 15 and 27?m depth below the top of the formation. This is thought to be related to the effects deep Plio-Pleistocene weathering, iron cementation of joints and increasing frequency of ‘non-healed’ joints in the transition from MW to slightly weathered (SW) rock.CITATION:Macklin, S, Schult, M, Terzic, Z and Chu, D, 2014. Strain-dependent stiffness of the weathered Melbourne Formation, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 179–188 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By Pollard D. M

The BHAS copper-lead matte leach process, developed in Port Pirie, South Australia, has been in operation on a commercial scale since 1984. This process is one of many developed in the past decade to recover copper via the hydrometallurgical route. In essence, the process involves a single stage agitative leach of 100% -75um matte in an acid chloride-sulphate lixiviant with gaseous oxygen as oxidant. The leach temperature is controlled at 85¦C to assist with reaction kinetics. After leaching, divalent copper is recovered from solution via a conventional solvent extraction/electrowinning circuit to yield cathode copper for sale The BHAS matte leach process has several unique characteristics cf. other commercial oxidative acid leach processes. These include i) the use of gaseous 02 as oxidant ii) H2SO4 addition as make up acid iii) Relatively low chloride ion addition (30 g/1) For this reason, extensive work was carried out into the optimization of leaching by Meadows (1985). Variables investigated included ò Oxygen flow-rate ò Agitation intensity ò Leach temperature ò Free acidity ò Chloride ion concentration ò Matte particle size The current work was conducted to determine the effect of cooling rate, and hence mineralogy, on the leaching characteristics.

Jan 1, 1989

By A Maier, M Goldner, C Gimber

Given the ongoing global crises of climate change and nature loss, with the World Economic Forum (WEF) identifying them as the top risks to global economies in terms of both likelihood and impact in the coming ten years (WEF, 2022), there is increasing, pressing demand for companies to demonstrate they understand their climate and nature related risks and look toward contributing genuine beneficial environmental outcomes. Within the mining industry, mine closure is the obvious field in which climate and nature positive strategy can be linked with operations. To do so, there is a need to challenge long-held assumptions around closure in the mining and regulatory context; particularly, to shift the focus from closing individual mines to considering regional opportunity generation and value creation.

Aug 2, 2023

By J Maxlow, M J. Woods, M P. Sandy

The Newcrest Mining Limited Telfer operation comprises both open pit and underground operations producing gold and copper. The underground operation is made up of three production areas, the sublevel cave (SLC), M Reefs narrow vein open stoping and Western longhole open stoping areas. With stoping situated on the abutments of a mature and active sublevel cave, the interaction between mining areas is often complex. This is particularly evident in the M Reefs orebodies with high levels of extraction in all four reefs, and reliance on pillars to maintain local and global stability. A key concern was the potential for a cascading pillar failure to develop and rapidly progress through the M Reefs stoping area. The monitoring plan needed to capture any change in overall stability and identify if deformation was caused by pillar failure within the M Reefs and hanging wall closure, or shear on the reefs caused by SLC influence.

Nov 29, 2022

By D Felipe, G J. Harbort

In the past 40 years substantial changes have occurred in flotation machines. This has included increases in mechanical cell size to 630 m3 , significant changes to flotation column aeration design and widespread use of the Jameson cell and other pneumatic flotation cells. Over the corresponding period there has been increased used of machine characterisation measurements to benchmark and optimise flotation circuit performance. JKTech maintains a database of industrial flotation machine characterisation measurements. The database contains over 4000 entries and includes gas dispersion measurements, such as bubble size, gas hold-up and superficial gas velocity, cell dimensions and impeller tip speeds. Data comes from numerous operating sites and commodity groups, including gold, copper, molybdenum, nickel, palladium, lead-zinc, platinum, silica, phosphate, coal and iron ore. Flotation duties registered include flash flotation, preflotation, roughing, scavenging and cleaner circuits. Measurements have been conducted on a wide range of flotation machines from different manufacturers. This includes forced air machines, such as Outotec and Dorr Oliver, and self-aerated machines, such as Denver and Wemco. The database also includes substantial flotation column entries, such as the Microcel, Eriez/CMT Slamjet and Jameson cell. This paper describes the flotation machine characterisation database and discusses the variation between different types of industrial flotation machines, in operating production circuits.

Aug 24, 2022

By Collins D. N

The Olympic Dam Copper Smelter Acid Plant is a hybrid plant capable of producing sulphuric acid from either sulphur burning, metallurgical gases or a combination of both. Commissioning of the Acid Plant on sulphur burning commenced in early April 1988 and commissioning on combined sulphur burning and metallurgical gas commenced in August 1988. During commissioning on sulphur burning a number of acid spills occurred due to balancing of tower flows and control of acid dilution. A number of other significant problems were encountered including failure of boiler gaskets, failure of strong acid pumps seals, the fracture of the teflon dilution water injector and the subsequent failing of the acid circulation pump, tank steel failures and various instrumentation problems. The Commissioning of the Acid Plant on metallurgical gases commenced in August and with the exception of the production of oleum in the boiler economizer was relatively trouble free. Oxygen Plant commissioning commenced in May 1988 and was without significant incident. An outline of the basic equipment for the Acid Plant and Oxygen Plant is presented together with aspects associated with the commisisoning of both plants.

Jan 1, 1989

Depletion of shallow ore reserves is forcing the South African gold mining industry to exploit reefs at ever-increasing depths. By 2010 around 30 per cent of South African gold production probably will come from depths greater than 3 km (Johnson and Schweitzer, 1996). At such depths, virgin stresses will rise significantly, producing complex rock engineering problems (Malan and Basson, 1998). Concern over structural instability at depth has led planners to seek a technology capable of ædetection of geological structures with a displacement of 2 m or greater (or as appropriate to the mining technique) 200 m ahead of mining at an acceptable costÆ. Borehole radar probably is such a technology. Cover holes are drilled routinely ahead of development. The evaluation of its candidacy for a tactical role in ultra-deep gold mining dependsùamong other thingsùupon establishing the electromagnetic characteristics of the environment hosting significant gold reefs. The Ventersdorp Contact Reef (VCR) is one such reef. Recent borehole radar field trials, presented here, suggest that the VCRÆs overburden is a remarkably translucent, clutter-free dielectric with a Q of ~35 and that the VCR itself is the dominant radar reflector.

Jan 1, 2002

By P Holtham, K Duffy, L Pyle, W Valery

The mining industry is becoming increasingly focused on pre-concentration due to its potential economic and environmental benefits, particularly for the more complex, low-grade, high throughput operations now being developed. Advances in technology have seen bulk ore sorting (BOS) trialled at several operations. However, BOS should not be seen as a ‘silver bullet’, it can offer significant benefits, but only under the right conditions. Deposits with interspersed mineralogy or disseminated, fine-grained minerals can be difficult for BOS. Large batches of barren or low-grade material are required for BOS to be effective. Hatch has recently completed several studies for clients who believed that bulk sorting was the most suitable pre-concentration technique for their operation, based only on an assumed sorter recovery or on laboratory trials of the chosen sensor. However, minimal consideration had been given to the heterogeneity of the deposit, the achievable separation batch size or sensor repeatability. Evaluation of BOS needs to consider both heterogeneity and sensor suitability. The valuable or gangue mineral must be present in such a way that it can be separated effectively in the large bulk sorting batch sizes, without competing minerals or changing ore characteristics affecting the metal upgrade or recovery. Also, the sensor chosen must be able to detect either the valuable mineral, a proxy for the valuable mineral, or a gangue mineral for rejection with sufficient accuracy and precision (repeatability). This paper presents three recent case studies, emphasizing markers which indicated that bulk sorting was unsuitable for the project whilst highlighting the pre-concentration technologies which were applicable (including particle sorting, and coarse particle gravity separation). The modelling methodology, equipment sizing and forward work plans developed to verify these alternative solutions are also presented, demonstrating the key factors contributing to a thorough scoping assessment.

Aug 24, 2022

By R M. Krek

The haulage system used to convey ore from an underground mine to a surface stockpile at the mine process plant is a vital component of the mine’s overall infrastructure and economic viability. The system selected has a significant impact on the set-up of the mine and the access to the underground mine. In turn, the set-up of the mine and the access to the underground mine have a significant impact on the system.A number of haulage technologies are available to transfer the ore from the underground workings to the surface stockpile, including hoists, conveyors, rail and trucks.This paper focuses on the shaft hoisting and inclined conveyor haulage technologies. These technologies have been used consistently to deliver ore from at depth and/or at high tonnage. Previous reviews of the appropriate vertical haulage systems have nominally been restricted to the respective systems only, with no consideration for any other scope or issues that may affect the selection. The selection of the appropriate vertical haulage system, whether shaft hoisting or inclined conveying, needs to consider numerous key factors.CITATION:Krek, R M and Northcote, A E A, 2014. A holistic viewpoint for selecting the vertical haulage system – shafts and conveyors, in Proceedings 12th AusIMM Underground Operators’ Conference 2014 , pp 289–296 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Mar 24, 2014