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By N Redwood, N Fowkes, A Bassom, S Durkin

"It is well known that from time-to-time a vehicle will interact with a bund or windrow and often the barrier is insufficient to safely arrest that vehicle. The result of such an incident is often catastrophic. Regulations around the requirement for edge protection near pit edges vary between jurisdictions. Generally in Australia regulations tend to be around placing the responsibility on the mine operator to provide ‘adequate’ or ‘appropriate’ edge protection. Guidelines often place a minimum height of bund at between half and two-thirds the diameter of the largest tyre on-site.Safescape has identified the opportunity to improve safety in open pit edge protection and is currently developing the Edge Protector (EP) product. The EP is designed to create a vertical front face to a conventional broken rock safety bund. The fundamental premise of the product is that by creating a vertical front face to the bund, trucks cannot easily drive up over the bund and instead have to push through the rock to get to the other side.In addition to providing a safer system for arresting vehicles, the vertical front face also means that extra space is made available in the haul road. This can either be used to facilitate larger trucks or when designing a new mine, with an increase in overall pit slope.This paper outlines the research and development of a new edge protection product. Discussion will include project objectives, economic incentive for mines to apply the system, mathematical analysis of the truck/bund interaction and physical testing of the product.Citation:Durkin, S, Fowkes, N, Redwood, N and Bassom, A, 2016. Innovative Approach to Open Pit Edge Protection, in Proceedings Ninth AusIMM Open Pit Operators' Conference 2016, pp 138–149 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 15, 2016

By M C. Ackland

The Grande Côte Mineral Sands Deposit (GCMSP) is located on a coastal mobile dune system in Senegal on the west coast of Africa. Senegal is a stable, democratic republic, having gained its independence from France in 1960. It has a population of about 12.5 million people. The dunes begin about 25 km north-east of Dakar, the capital city of Senegal, and extend northwards for more than 140 km. The mineralised dune system averages about 2 km wide with some areas extending to up to 4.5 km wide.Mineral Deposits limited (MDL), a Melbourne-based company with over 60 years operational experience in mineral sand mining in Australia, holds, through its Senegalese subsidiary MDL Senegal SARL (MDLS), a 25-year Mining Concession covering the deposits. The main heavy mineral (HM) areas identified to date are, from south to north, Mboro, Fass Boye, Diogo and Lompoul. Within the Mining Concession there is potential to identify additional resources beyond the limits of present drilling. The dunes are mobile or semi fixed, pale yellow in colour and overlie older white marine sands. The dunes range between 5 m and 30 m in height and the mineralised zones, which are essentially flat-lying, average around 15 m in thickness. The mineralisation consists, principally of ilmenite with accessory zircon, rutile and leucoxene. Zircon and ilmenite are the main commodities of interest.Independent consultants AMC estimated mineral resources for the four main deposits in 2006 of 1330 Mt of sand averaging 2.0 per cent HM at a cut-off grade of 1.5 per cent HM. At a cut-off grade of one per cent the resources were 3200 Mt averaging 1.5 per cent HM. All of the estimate was classified as Inferred Resources under the 2004 Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves (JORC, 2004).Subsequent completion of infill drilling, sampling and assaying of the initial mining area, centred at Diogo, was completed in 2008, enabling a final dredge path to be designed and ore reserves estimated, based on a JORC compliant Measured and Indicated Mineral Resource. Infill drilling is continuing in the Lompoul and the results of this campaign will be included in the JORC compliant data base by AMC in April 2010 to enable the 15 per cent year dredge path and mine plan to be finalised.Development studies have shown that the project can be optimised as a dredging operation, with mineralised sand being treated in a conventional floating spiral preconcentrator, wet concentrator and dry mineral separation plant. Engineering work now substantially completed by Ausenco Limited (Ausenco) has developed the combination of some existing plant from MDL’s past operations, and new plant for the complete process from dredging to final product separation and grading. Testwork on a series of bulk samples has determined that the project can yield a high quality zircon product and an ilmenite product along with minor rutile and leucoxene.Work to date indicates a likely output of around 80 000 t of zircon in various quality streams (Primary, Secondary, Standard and Foundry Grades), around 550 000 t of ilmenite plus around 15000 t of rutile and around 12 000 t of leucoxene/secondary ilmenite. Planned zircon output would represent around 7per cent of the total world production, which would make the GCZ&IP a significant producer on a world scale.The studies have indicated capital costs to be in the range of US$400 M total operating cost (after completion of ramp-up) of around US$50 M - $55 M/a. Revenue is expected to be in the range $127 M - $157 M/a.

Oct 5, 2011

By G Corder

The aim of the circular economy is to accelerate the transition from a conventional linear take-make-dispose economic model to a circular model. It is restorative and regenerative by design and aims to keep products, components and materials at their highest utility and value at all times. This extended abstract presents a brief overview of the circular economy, provides application of the circular economy in other industrial sectors including the downstream metals value chain and proposes how circular economy thinking could progress the development of complex orebodies.CITATION: Corder, G, 2018. Can the concept of the circular economy help unlock complex orebodies?, in Proceedings Complex Orebodies Conference 2018, pp 8–10 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

By J Theiler, B Beamish

The presence of reactive metal sulfide minerals in waste rock contributes to the hazard of spontaneous combustion in dumps, as these minerals react with air and water entering the dump at ambient temperatures to form various mineral products and significant heat. This reaction series can also be an initiator of self-heating of carbonaceous material present in the waste rocks if sufficiently high temperatures are reached. Characterisation of these reactive minerals has primarily been to assess the risk of acid mine drainage, which is not necessarily an indicator of spontaneous combustion risk. No systematic testing procedure has been adopted by industry to assess the spontaneous combustion propensity of the waste rock. As a consequence, the principal management strategy for spontaneous combustion has been a reactive approach of dealing with events as they arise.Recent advances in adiabatic oven-testing have enabled more definitive assessment of the spontaneous combustion propensity of coals, including the quantification of the accelerating influence of reactive pyrite (Beamish and Beamish, 2011, 2012; Beamish, Lin and Beamish, 2012). This same test procedure has been used to assess the self-heating performance of metal concentrates and is therefore amenable to assessing the metal sulfide oxidation process from low ambient temperatures. The data obtained from such testing can be used to quantify the more prone waste rock sequences of a mineral deposit in advance of mining. This enables appropriate management planning for emplacement and long-term storage of waste rock in dumps.CITATION:Beamish, B and Theiler, J, 2016. Characterising the spontaneous combustion propensity of waste rock, in Proceedings Life-of-Mine 2016 Conference , pp 93–96 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By I Douglas, L Allen

Localised indicator kriging was developed following a similar approach used by Marat Abzalov (2006) in his paper titled æLocalised uniform conditioning (LUC): A new approach for direct modelling of small blocksÆ. Abzalov introduced the idea of mapping panel distributions from uniform conditioning onto selective mining unit-sized blocks that were created using ordinary kriging. This concept of remapping panel distributions was applied to multiple indicator kriging histograms.At Newmont a program was developed that made the remapping of MIK histograms to SMU sized blocks extremely efficient and was subsequently tested on several gold deposits. The results have been encouraging as the localised indicator kriging (LIK) method has eliminated many issues that have plagued both ordinary kriging and multiple indicator kriging. Use of localised indicator kriging methodology limits the smearing of high-grade and the over-smoothing of grade that is common and difficult to control in OK but retains the ability for localising grades. LIK also simplifies change-of-support corrections, eliminates un-mineable slivers of low or high-grade when dealing with small tonnages, and allows for the mapping of linear and non-linear estimates into the same block.

Sep 26, 2011

By M Franklin, C Puglisi, S Fitch

Implementation of a well planned and executed Management Operating System (MOS) can result in widespread improvements to operational performance but its success relies heavily on the investment by and engagement of the larger workforce with the project. Over the seven month period of the Telfer MOS project, significant improvements were achieved; a 20% increase in monthly hoisted tonnes from the open stope and sublevel cave operations and a 45% increase in square metres of ore extracted from the narrow vein operation. The Telfer MOS was undertaken with the intention that the project wasn’t solely about producing new tools, it hinged on the investment and behaviours of the personnel affected by these tools and alterations. To ensure that the project ran smoothly, the Byrnecut senior leadership team and their operators were heavily involved in the project’s development. In the initial stage, Telfer’s MOS project determined that the quality and accuracy of the information received in the form of radio calls to mine control and completed operator plods was questionable. This required an overhaul of the data collection and verification process in the form of altered operator plods, which was then cross referenced with the operator’s radio calls to mine control. Once the data collection and verification process was implemented, the Telfer team was then able to produce several tools with the aim of providing visibility to the data being captured and its implications. These tools allowed the mine foremen to determine whether equipment was being under-utilised and where they should focus their production efforts to meet monthly targets. Whilst the initial underground project is now complete, the implementation of MOS across the entire site is ongoing with significant operating improvements occurring.

Mar 15, 2021

Project delivery in our current market is not as efficient as it could be. Industry at large (both client and consultant), is diligently following the engineer, procure, construct, manage (EPCM) or engineer, procure, construct (EPC) delivery models and not necessarily appreciating the underlying principles that make them the effective tools they were to start with. We often misinterpret project management with EPCM and end up with a literal and superficial interpretation instead of the disciplined risk reduction and business value capture exercise it is intended to be. One of these underlying principles is the project team as resource or commodity depending on which perspective we follow. Some of us understand this principle only too well and succumb to the temptation to take advantage of the imbalance in the understanding of EPCM by selling bodies and hours. Value and return on investment do not always come into the equation. The latecomers and aspirants are struggling with this as a barrier of entry into this lucrative market, since as we all know - people as commodity was becoming and still is a scarce resource. Clients are also waking up and asking why 1000 engineers on the floor are better than 100, when engineering design in all aspects of industry, new technology aside, is mature. Why is it that we start with a clean sheet of paper with every project or that neighbours in the same industry segment and location just happen to have completely unique conditions and circumstances that require totally original design (Local conditions aside)? The answers to this question appear when we explore the role of the project team and how it is structured. We will need to investigate team culture and levers for success. Then we will formulate a business case for a team to be able to follow traditional project management practices with EPCM delivery models but yet end up with an alternative look, feel and result. An outcome where more input is not necessarily better and the client and consultant both are aligned with success measured in dollars and a win-win outcome for both parties.

Jan 1, 2009

By K Watters

API Management Pty Ltd (API) is currently developing the West Pilbara Iron Project (the ‘Project’). The Project is a substantial greenfi elds mining and infrastructure development proposed for the west Pilbara region of Western Australia. The Project will establish API as a new and independent supplier of direct shipped iron ore. API manages the Australian Premium Iron Joint Venture (APIJV) on behalf of joint venture participants Aquila Resources Ltd and American Metals and Coal International Inc. The APIJV was formed in February 2005 with the objective of developing a long-term iron ore export operation in the west Pilbara region.Development of Stage 1 comprises a 30 million tonne per annum (Mt/a) channel iron deposit (CID) operation scheduled to commence in the second half of 2014 subject to approvals. JORC compliant CID resources total nearly 700 million tonnes and the Stage 1 mining area comprises eight iron ore deposits located between 30 km and 85 km south of Pannawonica. Run-of-mine ore from the eight deposits is transported to a central processing facility for crushing, screening and blending into a sinter fines product, which API has named West Pilbara Fines or WPF. Construction of a 282 km main line heavy haulage railway from the Stage 1 mining area to the proposed greenfields multi-user port at Anketell Point near Wickham, is capable of accommodating large Capesize bulk carriers and providing export facilities for other third parties. Capital investment in the order of $A6 billion includes essential support infrastructure including power, water, accommodation, roads and an airport at the mine.A feasibility study for the development of the Stage 1 mine, rail and port infrastructure has been completed along with environmental surveys of the mine, rail and port areas with Public Environmental Reviews (PERs) for each submitted for public review by end 2010. Consultation and cooperation with various stakeholders of the Project areas, and early engagement with traditional owners of the respective areas has commenced. Various sampling and metallurgical characterisation programs combined with independent institute and steel mill based testing have confirmed the positive sintering characteristics of WPF ore, which is higher in alumina (3.37 per cent) than typical Pilbara ores. *This is an abstract only. No paper was provided for this abstract.*

Jul 11, 2011

By W Y. Guo, L X. Chen, D X. Zhang

To obtain the rock type-I crack propagation process accurately, a novel fixture is used to make the prefabricated crack of rock propagation along the predetermined direction. In this study, the crack propagation process of rock is monitored with the digital image correlation method (DICM), and a mechanical model of crack directional propagation was established. The results show that the simple crack directional propagation device can effectively realise the stable propagation of type-I crack along the predetermined direction, the crack initiation angle is less than 10°, and the deviation between the peak strength of crack propagation calculated by a simplified mechanical model and the tensile strength of Brazilian splitting is 22.76 per cent and 7.53 per cent, respectively. According to the deformation field evolution law, crack propagation can be divided into three stages: microcrack development, main crack propagation, and main crack propagation. As for the rock type-I crack initiation and propagation mechanism, before reaching the peak strength, the prefabricated crack tip is subjected to maximum tensile stress; the elastic energy increases rapidly, and the dissipation energy increases slowly; after the peak strength, elastic energy exceeds its energy storage limit and released rapidly, and most of the input energy is converted into dissipation energy, which makes the crack propagation rapidly. The crack directional propagation device will be further optimised and improved, and it is expected to provide a new method for the study of crack propagation mechanism, rock failure precursor information and crack arrest principle, etc. It will also provide theoretical references for the optimisation of coal strata directional blasting, fracturing, fracture arrest, and other related technologies in geotechnical engineering.

Nov 29, 2022

By L Nagy, K P. Juhasz

The authors were engaged to optimise a traditional rebar cage reinforced concrete segmental lining by means of finite element analysis (FEA) using macro synthetic fibres for the Shanghai metro extension. The aim of this study was to reduce or entirely replace the original steel reinforcement of the segmental lining, in order to make the precast production process faster and more economic. The outer diameter of the tunnel was 6200 mm, the thickness of the segments was 350 mm.The numerical calculations were performed by Atena Finite Element software, which is based on the combination of Menétrey-William and Rankine failure surfaces on the compression and tension sides respectively. The effect of the macro synthetic fibres was modelled as tension stiffening on the tension surface.A one-to-one full scale model of an assembled tunnel ring using the original reinforcement cages was tested at Tongji University in Shanghai, July 2013. The ring was tested to differing load levels where load and displacement were measured until failure. The author’s first step was to calculate the real displacement characteristics of the original reinforced concrete (RC) ring, then calculate the numerically modelled version, so as to compare them. The material parameters of the concrete and rebar used had been determined through basic material tests conducted at the Tongji University. (Bi, Liu and Wang, in press).The numerical modelling undertaken has shown good correlation with the full-scale physical test results. Optimisation of the lining reinforcement was achieved through the addition of fibres, resulting in a substantial reduction of the steel rebar cages. Several results have been computed with the numerical model using different dosages of macro synthetic fibres, showing that the mass of steel reinforcement could be reduced by 50 and 75 per cent respectively.CITATION:Juhasz, K P, Nagy, L and Winterberg, R, 2014. Full-round numerical modelling of a macro synthetic fibre reinforced tunnel boring machine tunnel in the Shanghai Metro extension, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 477–484 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

The Institute of Geological and Nuclear Sciences (GNS) is commencing a project to develop a National Minerals Information System (NMIS) for New Zealand . Initially, the NMIS project will focus on providing public access via a web site to existing minerals related databases maintained by GNS and some other organisations. Core components are geological maps, GERM (Geological Resource Map), REGCHEM (Regional Exploration Geochemistry), PETLAB (rock catalogue), GEOCHRON (radiometric ages), mineral deposit models, mineral deposit profiles and 3D mineral deposit GIS databases. In addition to developing the web site, the project will include upgrades of some of the databases and the production of derivative products such as mineral resource and prospectivity assessments, and mineral inventories.

Jan 1, 2004

By R F. Cota, C Freeman, A Heberle

"The Lamego mine is an underground gold mine in the Iron Ore Quadrangle in Minas Gerais state, Brazil. The mine produces 48 to 50 koz per annum, as part of the larger Cuiabá-Lamego Complex. This combined unit is AngloGold Ashanti’s largest gold producer in the Americas, contributing with 310 to 320 koz per annum.The mine started production in 2009, utilising cut-and-fill mining methods.A mining method change was trialled in 2014, introducing open stope methods. The key benefits proposed from this change are considered to be: improved safety by eliminating re-entry mining methods reduced mining costs/increased productivity from utilising bulk-mining operations.The results from the trial were encouraging, and open stoping participation expanded beyond a trial.Production from open stope areas reached 180 000 t (40 per cent of total run-of-mine; ROM) in 2015. While the change in mining method resulted in higher production rates, it also introduced a critical issue in terms of stope recovery rate.Average underbreak (unplanned loss of ore) in the larger open stopes reached 21 per cent in 2015. To manage this ore loss, a project targeting higher recovery was structured with three primary components: analyse current performance to define contributing factors (design process gaps, operating practices) investigate corrective actions apply corrective actions and maximise team engagement to ensure changes become standard practice.Within six months of commencement, a range of contributing factors had been identified, and the majority of the associated corrective actions implemented, including increased team engagement to ensure changes were not ‘once off’ actions.The outcomes show a clear reduction in underbreak (average ~12 per cent for 2016), with further improvement opportunities identified. The challenging target is now to achieve a further reduction to 10 per cent underbreak as the average for 2017. The results contributed 1400 oz and additional US$ 0.5 million to the cash generation profile for 2016.CITATION:Heberle, A, Freeman, C and Cota, R F, 2017. Increasing stope recovery in an underground gold mine by using effective analysis, corrective action and employee engagement processes, in Proceedings 13th AusIMM Underground Operators’ Conference 2017, pp 117–122 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 16, 2017

By J Simpson, M Johnston

Recently Mount Isa Mines undertook a study to review the lead-zinc orebodies to extent of resource and reserves and determine the new life-of-mine schedule, as the Mount Isa and Hilton orebodies had not be reviewed for many years. Also, the recovered value of the Mount Isa, Hilton and George Fisher orebodies had been increased by major performance improvements in the lead-zinc concentrator. The Mount Isa Lead-Zinc concentrator processes fine-grained lead-zinc ore from the Mount Isa, Hilton and George Fisher orebodies. These orebodies have varying levels of pyrite and large variation in the grain size and texture of the galena, sphalerite and pyrite. This variation has a large effect on the recovery of the lead and zinc in the concentrator. Some ores achieve 90 per cent recovery at target grades, yet other ores are unable to achieve æsaleableÆ concentrate grade, with no metal being recovered to concentrate and therefore effectively losing the contained metal to the final tailings. Models were created to predict the metallurgical performance of these orebodies, to better reflect the variation that occurs. These improved metallurgical models and economic data allowed the determination of the Net Smelter Return (NSR) for each block in the geological block model. This NSR is the return to MIM of the metals contained in concentrate. The NSR was used as the cut-off grade criteria when determining the value of the ore. This formed the basis of the lead-zinc life-of-mine schedule and the optimisation of the lead-zinc business.

Jan 1, 2003

By Gregg PEH, Horne D, Bolan N, Stewart RB

The Tui mine site is situated on the NW flank of Mt. Te Aroha, at approximately 400 m altitude. During underground mining operations two lead-copper-zinc ore bodies were exploited and processed on site. The legacy of the mining operation is a barren dam containing over 100,000 m3 of sulphide-rich tailings. The Tui mine site is arguably the worst case of environmental degradation resulting from past mining activity in New Zealand. Although the impacted area (approximately 4 ha) is extremely small by international standards, acid mine drainage (AMD) emanating from the abandoned tailings dam and mine adits has severely contaminated local streams and prevented natural plant recolonisation of the site for more than 20 years.

Jan 1, 1995

By D Bruce

OZ Minerals’ Carrapateena mine is a Sublevel cave mine located in South Australia, approximately 160 km north of the regional centre of Port Augusta. Carrapateena commenced underground development in 2016, with production commencing in 2019 and ramping up to 4.25 Mtpa by December 2020. In pursuit of continual improvement, the Carrapateena mining team sought to identify how it could better interrogate its current productivity levels and its drivers (root causes). During this process the team were confronted by a disconcerting number of different opinions (which often conflicted) on our actual productivity performance which led to a need for review. Although reliable data and a well-designed time utilisation model (TUM) existed, it was still unclear what actions needed to be put in place to improve productivity. This was for the following reasons: • Data sources were disparate unless significant effort was applied to compile them. • Data sources were not available in a format that could be easily viewed or analysed. • General understanding of the data which was collected and how it could be used was poor. • Process of regularly analysing performance and forming tangible actions to improve was lacking rigour. A project was then started with the goal to fix the areas stated above. An initial requirements gathering exercise was undertaken to identify key data sources for site which returned a staggering 42 known systems which were then shortlisted to the key systems that contained operational data and could generate tangible improvements when analysed. This paper discusses the approach to selecting the OZ Minerals Insights Hub as the chosen platform, and the effort and collaboration between cross-functional departments that was involved in transforming the data so it could be displayed in a useful way. The data sources identified included a fleet management system, two planning databases, a control system historian, and a mobile fleet machine data system. New processes were also introduced to digitally capture daily commentary; this was achieved utilising SharePoint Forms. Data pipelines were then developed in the Insights Hub platform to automate the ingestion and transformation of the raw mining data into curated data models for end user consumption. Tableau dashboard packages have been created to support facilitation of short interval control, daily review meetings, and weekly review meetings as well as data analysis of key equipment and locations. These dashboards visualise the mining data models in a form that provides the user a clear picture of what has occurred, why it has occurred, and where to focus improvement efforts. This has resulted in a team which is more accountable, more equipped to assess the root cause of performance, and more regularly able to make data driven decisions. The next step? To build this out from Mine to Mill and create a data indexing tool which will drive self-service reporting, a data agnostic platform and predictive tools that help our people continue to be one step in front.

Mar 29, 2023

By P Velletri, N Gaylard

The management of wear surfaces in mining operations has remained largely unchanged since the inception of mining. Sacrificial wear liners are installed on the inside of chutes, hoppers and other equipment used to transfer bulk ore to protect the asset from abrasive wear caused by the flow of material. These liners are generally replaced at fixed intervals which may be determined based on historical wear rates or may be driven by other maintenance requirements for that asset. This approach does not always yield satisfactory results, especially for critical assets where the impact of downtime on production can be substantial. For such assets, a condition-based maintenance strategy has the potential to significantly increase productivity and reduce the total cost of ownership associated with the asset. However, for such a strategy to be successful, timely information on the actual condition (remaining thickness) of the wear liners is essential. This paper describes the development and implementation of a wear monitoring system that can be used to remotely and continuously report on remaining liner material thickness in real time. It details some of the challenges that were overcome when developing the system, including the design of a patented thickness measuring system that can be used in a variety of liner materials and is tolerant to the presence of ore on the wear surface. The paper also explains how a cloud-based approach enables data from the wear sensors to be integrated into external systems such as a data historian, which has been demonstrated through a collaborative project with one of the largest iron ore producers in the Pilbara. This ability to combine real time liner thickness information with other data sources, such as throughput, provides the foundation for the transition to a condition-based maintenance strategy.

Nov 8, 2021

By D R. Andrew, K T. Morrison, J F. Tiedgen

Waste blasting in iron ore operations can pose a number of technical challenges, including blasting through variable geology and blasting soft ground in wet conditions. Blast patterns are designed to be loaded with a specific range of explosives with unique characteristics and properties. Each explosive product will produce an optimal blast outcome for a given set of blast parameters and ground conditions. Sites characterised by softer rock typically require low-density, low-energy explosives. Historically, these products have contained a high ratio of porous ammonium nitrate prill and are only suitable for dry blastholes. When blastholes within a pattern are found to be unsuitable for such explosives due to wet, damp or muddy blasthole conditions, a new product is selected. While it is easy to switch products to match blasthole conditions, the different properties of the new non-ideal product can impact blast performance and increase loading times and costs.Flexigel™ is a solids-sensitised emulsion blend suitable for loading at variable densities and energies in dry, damp, muddy or wet blastholes. It is a universal product that can be loaded to match ground and blasthole conditions or complement other explosive products.At Fortescue Metals Group’s Cloudbreak site, Flexigel™ was trialled through a series of matched pair blasts in order to optimise blast outcomes in conditions that were non-ideal for existing explosive products and to reduce the overall cost of drill and blast operations. Flexigel™ yielded improved instantaneous dig rates and improved loading efficiency when compared to a traditional emulsion blend. The results also indicated that variable-density and variable-energy products afford greater flexibility for optimising blast outcomes across all ground and blasthole conditions trialled.Trials of Flexigel™ at Cloudbreak have shown that a variable-density solution is available for conditions where traditional explosive products are non-ideal. As such, Flexigel™ is able to fill a major void at any operation where the desired low-density, low-energy explosive product must be substituted for a more expensive traditional emulsion blend or heavy ammonium nitrate/fuel oil.CITATION:Andrew, D R, Morrison, K T and Tiedgen, J F, 2015. Flexigel™ – a variable-density solution, in Proceedings Iron Ore 2015, pp 413–418 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

Mobile mining equipment presents only a small portion (ten per cent mining project costs but the selected technology will determine to a large extent the mining performance and mine profitability. The actual performance of the selected mobile equipment technology will rely on the support functions, infrastructure, user interface and user acceptance. Optimising the technology to match the circumstances is an increasingly important phase in a mine feasibility study. Smartly done feasibility studies include the possible future needs of changing or building-up of the selected technology. In massive mining applications the machinery faces quite different challenges than in selective or small-scale mining applications. In massive mining applications the efficient and continuous move of large amounts of material has led to the use of increasing degree of automation. This higher degree of automation in a mining application, on the other hand, will be best applied to a smooth and streamlined mining process and operation. Mining methods like block caving support automated operation. Automated mobile equipment needs supportive infrastructure, monitoring and information transfer systems as well as well established working procedures. Too often the user interface and human factor is disregarded during the consideration of automation. Through the available supplier programming tools it is possible to see how much the selected technology provides flexibility in changing production or economical situations, when major rebuilds or replacements are necessary, and view the effects of all these on the mine economy. When adequate technology is available from various sources, the difference becomes from preparing for the future, managing costs and combining the best layout with the most suitable technological solutions.

Jan 1, 2000

By P Aspinall

Safe work Australia (SWA) has a number of proposed amendments to existing Workplace Exposure Standard (WES) values that may dramatically change how mining workplaces using personal gas monitoring instruments will operate. In consultation with leading gas monitor manufacturers and distributors, an assessment of common Australian alarm settings values and analysis of potential frequency of increased alarm likelihoods has been conducted. This assessment explores the relationships between current monitoring practices, using instruments as health and not just safety tools and identify what will be needed to minimise worker ‘alarm fatigue’ and for common tasks to continue safely. This paper provides the necessary information to aid industry and hygienists to be ‘future ready’ given the likely impact that order of magnitude reductions in time weighted average (TWA) values for NO2, SO2, H2S and other common gases will have on current working practices. Reductions to gas alarm values will provide significant challenges to existing work methods and will require, practical application of the pending future values. Improvements and awareness of instrument capabilities by safety and hygiene professionals will better utilise gas monitors real-time data monitoring capacity and no longer be just ‘safe or not-safe’ instruments. The presentation seeks to promote the practical steps required in setting alarms based on risk consequence and likelihood, increase general awareness of the tools and data available in modern instruments and will enable industry professionals to better manage the challenges of any potential future changes.

Apr 16, 2024

By D Hunter, N Cusworth, J Miller

"Recent project failures have called into question the use and relevance of benchmarking and independent reviews, forcing a rethink of traditional processes and procedures.With cost estimates and schedules dramatically varying from lows seen around the global financial crisis to peaks experienced in the recent mining boom, benchmarking has ranged between essential and misleading.Profound shifts are now underway in future project delivery strategies as the market moves away from cost-plus engineering, procurement and construction management. The current trends in project implementation are to utilise more lump-sum design and construct or fixed-price supply and construct contracts. This trend will remove transparency in detailed cost information by reducing the sources and clarity of cost data.Independent peer reviews (IPRs) of studies and investment recommendations performed over the last decade have both failed to prevent flawed or deficient projects from proceeding to approval and funding, and been successful in ensuring that owners did not proceed with doomed investments.In recent times, it has been recognised by some owners, contractors and engineers that traditional benchmarking checks or IPRs, or a combination of both, will not necessarily produce reliable assessments of study conclusions and of the forecasts of project outcomes. To be of value, the benchmarking process now also needs to recognise the highly volatile responses from the engineering and construction industry to the current and future markets for their services.Similarly, reviewers who draw upon benchmarks of past project experiences on an understanding of the things that shaped and influenced their outcomes need to be more aware of how a future dynamic market may impact the outcome of the projects and raise warning flags accordingly.With the commodity cycle currently approaching what is hoped is its bottom, ensuring that benchmarking and independent reviews evolve into reliable, transparent and worthwhile processes becomes even more important. This can only be achieved with more transparent and analytical benchmarking and business-orientated reviews that both recognise and calculate the impacts of dynamic markets on project implementation.CITATION:Cusworth, N, Hunter, D and Miller, J, 2016. The role of benchmarking and independent reviews, in Proceedings Project Evaluation 2016, pp 249–259 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 8, 2016