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By D H. Laubscher

The in situ rock mass rating system û IRMR - leading to the mining rock mass rating system - MRMR - for jointed rock masses has been used (and abused) in mining operations around the world for the past 27 years. Despite the recent development of elaborate design procedures and computer-aided design packages, MRMR remains one of the most versatile and practical mine design systems available. It is important to realise that the rock mass classification system should not be replaced but rather complemented by more sophisticated and detailed design procedures. The classification system is not only the æcrudeÆ method used for initial assessment (as described in some geotechnical literature) but also in many respects a very effective and practical engineering tool. MRMR could, and should be used during the entire stage of mine life as an integral part of the design process. The objectives of this paper are to illustrate using practical case histories from the past decade, some of the pitfalls of the MRMR classification system, to clarify certain misconceptions in its application and update its mining application.

Jan 1, 2000

By D Teyhan, J Kirsch

Traditionally, most Australian iron ore mining operations have been surface-based. Processing plants were designed to handle dry ores. In recent years mining operations in the Pilbara have progressively moved below the water table exposing wet, sticky ores which have caused lost efficiency in screening operations as particles tend to agglomerate and adhere, blinding screening media. Miners and vibrating screen manufacturers have experimented with a shift from linear motion to elliptical motion screens. Elliptical motion conveys and lifts particles. Effective on flat deck (horizontal and inclined) or sloping decks it can be configured to provide a controlled transport rate, applying pressure in all directions to maximise screening efficiency. In practice, elliptical motion screens have proven to be effective in dislodging sticky particles from screening media, reducing blinding rates and improving screen efficiency. Moisture and clay content change during the life of a mine. These changes are sometimes the effect of seasonal rainfall, in other cases due to increased groundwater and clay content as mining operations go deeper. To compensate for such changes and optimise screen efficiency, changing the ‘shape’ of elliptical screen motion is required. This has traditionally required shutting down processing plants and making mechanical screen adjustments. Plant downtime is costly and machine adjustment has been a ‘trial and error’ practice. This paper will explore the results of a field trial that is currently underway in Brazil of a next generation elliptical motion screen design that allows operators to make changes to exciter rotational direction, speed and screen stroke angle, through electronic drive phase control. The machine’s electronic drive system synchronisation is enhanced for stability with a unique mechanical timing system. Operating at up to 6 g, screen adjustments can be made on the fly without stopping production. Early trial results are showing up to 50 per cent improvement in screen efficiency compared with traditional elliptical motion machines under certain feed conditions.

Aug 24, 2022

By D Teyhan, J Kirsch

Traditionally, most Australian iron ore mining operations have been surface-based. Processing plants were designed to handle dry ores. In recent years mining operations in the Pilbara have progressively moved below the water table exposing wet, sticky ores which have caused lost efficiency in screening operations as particles tend to agglomerate and adhere, blinding screening media. Miners and vibrating screen manufacturers have experimented with a shift from linear motion to elliptical motion screens. Elliptical motion conveys and lifts particles. Effective on flat deck (horizontal and inclined) or sloping decks it can be configured to provide a controlled transport rate, applying pressure in all directions to maximise screening efficiency. In practice, elliptical motion screens have proven to be effective in dislodging sticky particles from screening media, reducing blinding rates and improving screen efficiency. Moisture and clay content change during the life of a mine. These changes are sometimes the effect of seasonal rainfall, in other cases due to increased groundwater and clay content as mining operations go deeper. To compensate for such changes and optimise screen efficiency, changing the ‘shape’ of elliptical screen motion is required. This has traditionally required shutting down processing plants and making mechanical screen adjustments. Plant downtime is costly and machine adjustment has been a ‘trial and error’ practice. This paper will explore the results of a field trial that is currently underway in Brazil of a next generation elliptical motion screen design that allows operators to make changes to exciter rotational direction, speed and screen stroke angle, through electronic drive phase control. The machine’s electronic drive system synchronisation is enhanced for stability with a unique mechanical timing system. Operating at up to 6 g, screen adjustments can be made on the fly without stopping production. Early trial results are showing up to 50 per cent improvement in screen efficiency compared with traditional elliptical motion machines under certain feed conditions.

Nov 8, 2021

By S Harrison

Work health and safety duties around Australia include duties to manage psychosocial health and safety (mental health) of workers engaged by businesses or undertakings and of other persons impacted by the operations of the business or undertaking. Persons conducting a businesses or undertakings must develop systems of work and policies and procedures for ensuring, so far as is reasonably practicable, the safety and health of workers and other persons. Officers have a duty to exercise due diligence and to ensure effective systems are developed, implemented and resourced. The developed systems will only be effective with worker’s co-operation and engagement. The duties placed on workers by work health and safety laws are an important part of the safety matrix of obligations. Supervisors and Leaders are workers and they play a critical role in delivering health and safety outcomes. To deliver these health and safety outcomes with respect to psychosocial safety Supervisors and Leaders need to understand their obligations and have a framework to use to assist them in understanding what workers require and what steps need to be taken to meet their duties. They also need to take steps to assist those workers that they supervise to meet their duties.

Apr 16, 2024

This report will differ slightly from the traditional scientific and technical discussions given at this type of conference. It will focus on the personal experiences and choices that I undertook when deciding on my graduate position and location after completing university studies. Throughout the duration of my course I had experience in both fly-in, fly-out operations in the Pilbara and residential operations in the West Australian Goldfields. These experiences, though limited, allowed me to explore the two different methods and their pros and cons, and consequently to make my choice for graduate employment. Throughout the duration of my degree I believed it was important to gain a basic understanding of the two methods, focusing on lifestyle and personal interactions. The decision that a residential site suited my personality and lifestyle then allowed me to refine my job applications to a more specific list of mine sites and companies, resulting in a residential position with BHP Billiton at their Iron Ore operations in the Pilbara, Western Australia.

Jan 1, 2005

By L Hussey

Mt Keith concentrator treats low grade disseminated nickel sulfide ore supplied from the adjoining open pit mine. It is a traditional crushing, two-staged closed circuit grinding circuit (SAG & Ball Mills), followed by a complex split-size rougher, scavenger and cleaner flotation circuit. In 2016, 10.5 Mt was milled, at an average head grade of 0.54% Ni, yielding 35 000 nickel metal tonnes in concentrate.Historical analysis of the plant data indicated that of all the nickel lost in the fines rougher circuit tails stream, 25.6% was recoverable in an eight minute laboratory scale flotation test. These results implied that this fine nickel was readily available for recovery in the plant, either through operational improvements or additional flotation capacity. With operation optimisation ongoing, and capital within the business focused elsewhere, plant personnel were challenged to think differently about improving recovery.In 2012, a separate project to improve plant recovery when treating high talc ore was completed. Amongst other vessels, this project saw the installation of two 150 m3 Outotec Cells to the scavenger section of the fines rougher, middlings and scavengers (RMS 1) circuit. Since installation, the operation of these cells resulted in difficulties immediately upstream with instability in the scavenger cells. It was therefore decided that these cells would be better suited to treating the fines rougher circuit tails.The alterations required to divert these flows were minimal, with the capital project totalling $220 000.In the two years since installation, the fines rougher tailings nickel grade has dropped by 9.9%. The scavenger circuit has also seen a 2.8% reduction in tailings nickel grade, and instability issues were immediately resolved. This project serves as a lesson in how existing plant infrastructure may be better utilised to maximise recovery. Although this is especially applicable when capital constrained, such re-appropriation can be considered at any point to maximise return on existing assets. CITATION:Hussey, L, 2017. Repurposing flotation capacity at Mt Keith nickel concentrator, in Proceedings MetPlant 2017, pp 254–258 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 11, 2017

By B Beale

Bow-tie analysis is a commonly used tool to identify and display risks that have the potential for an undesired hazardous event. The output of the analysis are bow-tie diagrams, which are an effective and versatile communication format that can be applied to any type of risk. Contrary to their simplicity, a proper bow-tie diagram that maintains its usefulness and clear communication is difficult to build. Over two decades assisting Major Hazard Facilities with bow-tie analysis for Safety Cases, several common mistakes have been identified. This paper aims to highlight those issues with examples and provide improvement strategies. A sample of the most common mistakes are: - overly complicated risk analysis - poorly scoped and defined terms - poor descriptions and justifications - identifying too many dependent controls. Overly complicated risk analysis leads to wasted time in obtaining data for little gain. The bow-tie diagram is only a model. Effort should be redirected into identifying and managing controls that will make a tangible difference to site risk. Broad scopes lead to enormous and confusing bow-tie diagrams for both the user and the workshop team. Defining the scope of the study, the consequence severity of interest and critical control characteristics creates focused workshops and targeted analysis. With more definitive scope, there may be more bow-tie diagrams, however, they are succinct and specific. Well described causes are imperative for clear communication to users, regulators and future bowtie review workshop groups. It is best to use common wording structures and explain the event stepby- step. Also, clearly document any likelihood calculations and use data references where applicable. Identifying all possible controls creates a false sense of security that there are many layers of protection. In reality, most controls are dependent on a single system or person and could all be compromised from a single failure. A definition of a ‘bow-tie’ control is required whereby it must be independent from other controls. Improving the bow-tie analysis process will assist operators in developing meaningful and ‘operational’ bow-tie diagrams to support risk management systems and practices.

Apr 16, 2024

By R J. Romañach

The theory of sampling (TOS) is now followed in the development of near infrared (NIR) spectroscopic methods for the pharmaceutical industry. TOS has been the guiding light for a two-step approach for spectroscopic composite sampling available for the development of real-time analytical methods for particulate-based industrial processes. The two-step spectroscopic sample composite has been used in the development of process analytical technology (PAT), an important regulatory initiative to improve the quality of pharmaceutical products. The two-step sample composite approach overcomes the low sample volume analysed by PAT methods; one of the key limitations to PAT implementation in the industrial production of particulate-based materials.PAT methods need to be validated demonstrating their accuracy, precision, specificity and robustness. TOS provides a deeper understanding of these validation studies which involve discrete particulate material. The validation of PAT methods is now being performed considering both sampling and analytical errors, while practically all previous method validations only addressed the total analytical error (TAE) of these methods. This has been a crucial impediment for the field of chemometrics as well.PAT is a key element of continuous manufacturing (CM) processes, which are considered an emerging technology capable of increasing the flexibility, agility and robustness of pharmaceutical processes while reducing their costs. The outflow of the continuous process is a 1D lot, and variographic analysis has been shown to discern process variation from sampling and analytical errors in pharmaceutical CM processes. Thus, variographic analysis is a process improvement tool with significant potential for improving CM processes. The possibilities for improving pharmaceutical manufacturing are enormous.CITATION:Romañach, R J, 2017. Theory of Sampling – from missing link to key enabler for process analytical technology, in Proceedings Eighth World Conference on Sampling and Blending , pp 63–68 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2017

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

By M Pyle, T Vizcarra, G Ballantyne, B Foggiatto

Bulk Ore Sorting (BOS) has the potential to add significant value to mining operations by manipulating the feed grade and throughput to the processing plant. However, assessing the performance of BOS is complex, as it is influenced by geology, equipment, spatial and time domains. This increases the risk (real and perceived) of the technology. To manage risk, brownfield operations have the option to: (a) first test the variability in feed grade using a detector on the feed conveyor and subsequently construct the diverter and associated materials handling equipment when the value is established; or (b) conduct site trials with standalone sorting plants. The approaches described for brownfield projects are not available for greenfield projects where the in-situ heterogeneity needs to be quantified and translated into an economic evaluation to test the viability of BOS. Ausenco has developed a methodology that allows assessing the in-situ ore heterogeneity and uses an in-house technoeconomic model to determine the value of BOS for greenfield projects and assess the effects of sorting performance on project economics. The in-situ grade heterogeneity can be measured on a length of drill core and fitted to a mathematical model to assign a heterogeneity index. Given the spatial location, this heterogeneity index can be mapped across a deposit in combination with the average grade. Linking this information with relevant mixing models can determine the likely technical performance of BOS at an operation. However, the real value is only realised when this technical understanding is linked with an economic model and used to optimise the mine plan. Three case studies will be presented that show how Ausenco applies this methodology to assess the value of bulk ore sorting for greenfield studies.

Nov 10, 2020

The Pongkor Gold Mine employs 678 staff. The mine is owned by the Indonesian state company PT Antam Tbk and is located 100 kilometres south west of Jakarta, in Java, Indonesia. Mine and infrastructure development started in 1992 following intensive geological exploration over 15 years. First gold production was in June 1994. The mine comprises three main orebodies: Ciguha, which is nearly mined out, dips at 75¦ from surface to 150 m. Kubang Cicau, dipping at 80¦ from surface to 230 m, and averages 3.5 metres thick at a grade of 10 g/t Au and 128 g/t Ag; and Ciurug, dipping at 60¦ from surface to 300 m and averages eight metres thick at a grade of 14 g/t Au and 172 g/t Ag. Present global ore reserves are 4.6 million tons at a grade of 12.3 g/t Au and 133.6 g/t Ag. Exploration is continuing for new veins. Initial mining was by manual cut and hydraulic fill at Ciguha, followed by Kubang Cicau. In 1996, it was proposed to convert Ciurug to a mechanised cut and fill operation. Two single boom jumbos and three load-haul-dumps (LHDs) were purchased with the assistance of a gold loan from NM Rothschild and Sons. Implementation of this upgrade was delayed by both a national economic crisis and an invasion of the concession by illegal miners. It was not until May 1999 that raise bore vent rises and access drift infrastructure commenced. Major underground development started in 2000 and is continuing. Production cut and waste fill stoping started in July 2001. The change from manual to mechanised methods has required a total change in work practices and attitudes. However, the process has resulted in a production increase from 600 tpd to 1200 tpd. A three-month compliance test (a condition of the financing loan) was successfully completed, from July to September 2001, with an average production of 700 tpd at Ciurug and 500 tpd from Kubang Cicau.

Jan 1, 2002

By W J. Shaw

Mining operations must become more predictable to overcome the volatility that has characterised the mining industry. Comparisons of production against predictions will become more consistent as mining operations merge and expand, as personnel move from site to site, and as public reporting of reconciliations becomes more prevalent. More consistent approaches are already being seen in the industry using the terminology used in this paper and elsewhere.Examples are provided that show how use of the waterfall chart as a reconciliation management tool can provide objective analysis to improve practices.Geometallurgical modelling is becoming more useful and will continue to do so as we move from a few bulk samples to better interpretation of material properties from geological mapping and drill sampling. Reconciliation has evolved to the stage where predictions of geometallurgical properties to optimise mill performance, and of geotechnical properties derived from better 3D geological models, should also be reconciled.CITATION:Shaw, W J, 2014. Reconciliation – outcomes and expectations, in Proceedings Ninth International Mining Geology Conference 2014 , pp 123–128 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 18, 2014

By R Steven

"Surveying, and as a result, surveyors, have been around since the start of time, and it has been said that so has their methodology!The theodolite and tape have been the backbone of a time-tested practice that has led to ground breaking advancements such as electronic distance measurement (EDM), global positioning system (GPS) and positional laser scanning. However, it was the introduction of the unmanned aerial system (UAS) that has allowed mine sites such as St Ives to take the next step towards truly turning survey data into metadata.This paper will explain how the unmanned aerial vehicle (UAV) was adapted to meet the requirements of a mine site supporting a major open pit operation, and how the open pit mining team adjusted their planning and production processes to maximise use of the extra data and information available to them.The advantages of the system include point cloud surveys with corresponding large-scale up-to-date photography and computer generated high detail contouring of mined areas that are then incorporated into the mine plan. All the while, the use of the UAV must be tailored to each specific problem encountered and a solution then matched.Citation:Steven, R, 2016. Trials, Tribulations and Triumphs of Unmanned Aerial Vehicle Surveying at St Ives Gold Mine, in Proceedings Ninth AusIMM Open Pit Operators' Conference 2016, pp 170–184 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 15, 2016

By S Graskoski

The allocation of boggers and trucks at Telfer’s sublevel cave mine is currently assigned by manual techniques, with decision-making primarily dependant on the judgement of the operators and mine control. Field observations indicate that allocation decisions could be improved by establishing a systematic approach to dispatch. An investigation into the current state of technology determined that no currently available solution would provide a tool to make optimal decisions for the Telfer dispatch challenge.In an underground sublevel cave (SLC) environment, the destination decision is fixed and the source is variable, so open pit and block cave solutions are not relevant. Newcrest underwent a development venture with an external vendor to develop a novel production dispatch algorithm and user-friendly software program to make allocation decisions in a systematic way with consideration given for the true complexity of the operation.This new production software, nicknamed Dingo (for Dispatch ‘n’ Go), is a smart way to assist forepersons and mine control operators in their day-to-day roles of planning shifts and allocating trucks and loaders to optimal locations during shifts.CITATION:S Graskoski, 2017. Dingo – an optimisation tool to solve complex short interval control at Telfer underground mine, in Proceedings 13th AusIMM Underground Operators’ Conference 2017, pp 261–266 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 16, 2017

In a previous paper in these Proceedings(l) it was shown from a study of the bore'logs and analyses then available, that the brown coal seams of the Latrobe Valley areas show progressive changes in composition with increase of stratigraphic depth, equivalent to a rise in rank: These changes appear as:(i) An increase in ultimate carbon and hydrogen, calculated on a dry, ash-free basis, and(ii) An increase in calorific value, calculated on the, same basis, each of the order of 1% per 100 ft. of depth, and(iii) A decrease in moisture content of the order of 0.5% to 1.0% per 100 ft. of depth. The decrease in moisture content was found to be less regular than the other changes. In some bores the moisture content remained more or less constant throughout a single seam, or fluctuated slightly, decreasing stepwise on passage to the seam below.It was noted that individual analyses within a bore showed irregular fluctuations, tending to mask the general trend in composition change. This was particularly so for the moisture content, which had been determined for 10 ft. lengths of core, whereas the other components were determined for 50 ft. lengths of core. Averaging of the moisture contents over 50 ft. lengths reduced the masking effects of these irregularities. The suggestion was made that these irregularities arose from variations in the relative proportions of pollen, resin, wood (lignite) and woody attritus composing the core. Such variation in the coal seams has since been established in some detail for the...

Jan 1, 1948

By J Vann

Geometallurgy is inherently multidisciplinary and it gains its power to deliver improved outcomes for the minerals industry by bridging silos between disciplines. This cross-disciplinary approach unlocks value, identifies (and avoids) value destruction and provides a pathway to better implementation of an energy efficient and sustainable minerals industry. Despite this promise, we argue that the cross disciplinary approach also represents the greatest threat to the success of geometallurgy. Some key cross disciplinary issues identified are:Geometallurgy has so far evolved in the technical sphere, mainly by collaborations of geologists and metallurgists. Consequently, in many cases the business dimensions and value have not been incorporated. Financial and risk evaluation viewpoints need to be assimilated into the geometallurgical paradigm. In fact, until such measures are integrated into practices, the value cannot be fully demonstrated.The historical and current efforts on geometallurgy have been highly focused on improved sampling and measurement of geometallurgical properties or appropriate proxies. This work has been driven by professional and academic geologists and metallurgical engineers. It is notable that mining engineers (who are critical in the value delivery of geometallurgy through changed planning approaches) have so far been at the margins, or absent. The construction of valid three dimensional (3D) geometallurgical models raises some important organisational, mathematical and geostatistical considerations. The enhancement of resource models to account for geometallurgical aspects must be managed carefully if the full value of geometallurgical thinking is to be realised.The use of 3D geometallurgical models to change business decision making and practices is the real nub of the problem. We believe sophisticated scenario based evaluation methods are required if the potential impacts of spatial rock properties on processes further down the mining value chain are to be realistically evaluated. Such changed practices require ‘whole of value chain thinking’ to embed this change into the business in an ongoing way.Because profitable geometallurgy demands changed approaches to business decision-making and also organisation of the firm (radically changed in some cases), the senior executive viewpoint must be incorporated into the language and thinking of geometallurgy. This is unavoidable if the establishment of a geometallurgical approach to project evaluation, development and operation is to be successful and sustained.A powerful analogy for the problem faced by geometallurgy is the transformation of safety culture in the mining industry in the past 20 years. We argue that, as in the safety revolution, explicit models, cultural change and management of the ‘soft’ dimensions of the problem are pivotal to success of geometallurgy. In light of this, we propose a model (‘the Geomet Curve’) that gives a framework and pathway for geometallurgy in seven steps. The implications of this model for technical and organisational steps required at different stages are discussed.

Sep 5, 2011

By S Dunham

For decades we’ve been focusing on reconciliation as a tool to validate mineral resource estimates. And for decades we’ve been misleading ourselves. The concept of reconciliation is simple. Predict, measure, compare and assess the quality of the prediction. This four-step process reflects the ideas of statistical process control and the plan-do-check-act cycle of Shewhart and Deming fame and our intuitive understanding of using system feedback to improve performance. In an ideal world where data is robust and dense this type of feedback loop can be useful. In the mining industry however, there are some fundamental flaws with the conceptual framework. At almost every stage of the process from pre-estimation through to final production the mining system is plagued by material challenges with data and measurement quality and quantity, system delays, and losses from a supposedly closed system. These issues can and do impact on the benefits sought from reconciliation. Instead of providing feedback leading to improved estimation, reconciliation can result in poor decisions, distracting investigations, and exacerbate the noise in an already noisy system. Before we can rely on reconciliation as a management tool, we need to address the multiple challenges present in our everyday practices. Some of the most critical issues are addressed in this paper.

May 24, 2023

By V Rasouli, G Cavanough, A Mokaramian

The sampling time, the costs and its quality are the three factors that determine the best method of drilling in mineral exploration. The two principal methods of reverse circulation (RC) and diamond core drilling are often used in combination by mine operators. RC is used for drilling shallow holes and in-pit grade control, and core drilling for deeper holes to identify future resources. The RC method is faster and more flexible than coring and provides virtually uncontaminated cuttings (ranges from dust to 25 mm chips) to the surface cyclone suitable for geochemical anomalies. The diamond coring produces core samples to increase the level of geological knowledge and the 3D extension and distribution of the orebody. However, both of these methods are subjected to certain limitations and inefficiencies in reaching deeper depths and drilling complex hole geometries. Examples of such shortcomings include the inability to provide enough air pressure for RC drilling and high friction between drill pipe and the hole wall in diamond core drilling.Considering that delivering large volume of reliable samples from deep zones to the surface in shortest possible time is of paramount importance in mineral exploration, and assuming that obtaining core samples over whole overburden is not always essential, then drilling small size holes as fast as possible and delivering the small chip samples to the surface would be a good alternative with several advantages over conventional drilling methods for deep hard rocks mineral exploration. As a result, the use of coiled tube (CT) drilling technology has been proposed recently for such applications. CT is a continuous length of ductile steel or composite tube stored and transported on a large reel; and allows fast drilling by eliminating the connection time and providing continuous circulation during drilling. This enables quick access to the zone of interest to collect the cuttings or obtain core samples. CT is advantageous particularly in drilling directional boreholes and multi-laterals. In this paper, feasibility of using CT delivering reliable samples is discussed for deep mineral exploration. In addition, recent developments and practices are presented that make CT a reliable drilling technology to drill cheaper, faster and deeper and to deliver more continuous and reliable data and samples from deep formations.CITATION:Mokaramian, A, Rasouli, V and Cavanough, G, 2012. Quality sampling using coiled tubing drilling in deep mineral exploration, in Proceedings Sampling 2012 , pp 73-80 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 21, 2012

By R Shaw

There are many small to medium carbonate hosted complex zinc containing deposits where the zinc is not economically recoverable either as concentrate or metal. High grade (>20% Zn) run of mine ore can be processed but even this material gives relatively poor returns. Considerable effort has gone into developing new technology for either upgrading the ore and/or recovering zinc metal hydrometallurgically but there has been limited success. Minetometal has developed a process capable of economically treating these deposits to give marketable lead and zinc products. This paper reviews alternative processes for these ores and gives a detailed description of the Minetometal Process. CITATION: Shaw, R, 2018. Processing carbonate hosted zinc-lead ores, in Proceedings Complex Orebodies Conference 2018, pp 130–131 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

By K Cochrane

Time and time again history shows us that mine closures are sustainability failures. Mine operators do not know how to turn the mine closure into an asset and communities around the mine do not know how to plan or what to implement to be sustainable when the mine needs to close. If we want to achieve sustainability when we close a mine, we generally need to consider what economic activity we will have to create leading up to the mine closure to ensure that the communities remaining in the area are not worse off after mining than before. There is not one silver bullet solution to mine closure, as all mines are affected by different environmental and socio-economic conditions. That is one of the reasons why mine closure is so difficult.Effective stakeholder engagement is the nucleus around which sustainability is built. Achieving sustainability as part of mine closure means not only a self-sufficient community, but also could lead to transformation of that asset.A key issue is that neighbouring communities become completely reliant on the mine. The mine has influenced the economic, environmental and social aspects of the community and with no alternative economic sources. The community and municipality will struggle with capacity to maintain infrastructure, services and jobs. This not only impacts the mine workers and their families but also other businesses and people in the town that make a living by servicing the needs of the workers and their families. Social problems associated with a mining operations and closures need to be considered. The misuse of alcohol, domestic violence, breakdown in law and order, economic and health issues all have a severe influence. Families often need to relocate from the mining town to find work. This further perpetuates the impact of the mine closure to the economic viability of the town. CITATION:Cochrane, K, 2018. Is your mine closure a sustainability failure? Transform your asset and create a self supporting neighbouring community. It’s as easy as ABCD!, in Proceedings Life-of-Mine 2018, pp 38–42 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 25, 2018