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By S Bhandari

A model for predicting dust plume dispersion from blasting operations using the Eulerian mathematical algorithm has been developed. This model considers atmospheric stability, and wind velocity and direction for computing dust concentrations at different distances from the blast. Software has been developed which simulates the movement of a dust plume at a given horizontal distance from the blast location and time elapsed after the blast. The concentration of dust is also given in vertical planes. It takes into account ground profile and atmospheric conditions such as temperature, pressure, humidity, wind velocity, wind direction and shear. Experiments were carried out in two limestone mines to calibrate the accuracy of the predictions made by such model. High volume dust samplers were used to collect dust samples. Difficulties encountered in satisfactory dust sampling and quantification of results have been described.

Nov 8, 2011

By E Widzyk-Capehart, P Vallejos, R Asenjo, J Ruiz-del-Solar

Throughout the minerals industry, it is evident that a new wave of technological innovation is needed as the mining sector looks for ways to achieve higher security and safety as well as higher production rates with less investment. Innovation has always been one of the key factors in achieving success within the mining industry. However, its importance will be especially relevant in the coming years if negative trends in commodity prices and new challenges facing the industry (lower grades, deeper mines and economy of scales) are to be overcome and the future sustainability and profitability of the sector ensured.The drive towards fully autonomous operations has begun, with the implementation of automated systems in both surface and underground operations. However, these automated systems are currently planned and realised with well-defined automated tasks within structured environments and isolated spaces. Currently, there is no interaction between automated systems, manned systems or humans, which creates physically isolated environments.For fully autonomous and continuous operations, the automated systems need to operate in environments that enable flexible interactions between automated machines, tele- and manually operated machines and humans.In this paper, we address the automation paradigm considering the synergistic collaboration between humans and automated systems. In this paradigm, humans and machines would interact in a flexible, collaborative and synergistic way without the need for isolation. The implementation of this concept within mining operations will have to be underpinned by science and technological developments and will require adaptation from many fields, including robotics, automation, distributed systems, communication, human factors, pattern recognition and mine design.The paper also presents the research and development work being undertaken at the University of Chile’s Advanced Mining Technology Center, in collaboration with the Chilean mining industry. This will provide the basis for flexible interactions between humans and technology-based systems towards a future of autonomous and continuous mining systems.CITATION:Ruiz-del-Solar, J, Widzyk-Capehart, E, Vallejos, P and Asenjo, R, 2015. Synergistic collaboration of humans and automated systems – innovative steps towards fully autonomous and continuous mining systems, in Proceedings Third International Future Mining Conference, pp 83–94 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 4, 2015

By O Handayani, R Barr, E Isaaks

The mining industry has focused a great deal of attention recently on the impact of blast movement on grade control. Although the problem of blast movement and its contribution to dilution and ore loss is well known, solutions to the problem are less than satisfactory. Perhaps the most recent innovation is the application of blast movement monitoring (BMM) devices to quantify blast movement. These devices emit an electronic signal and are planted at surveyed locations within the preblast material. Following the blast, their new locations are found using an electronic scanner. The magnitude and direction of the blast movement is given by the vectors between the pre- and post-blast BMM locations. However, it’s not clear how the BMM vector data can be best used to minimise dilution and ore loss. One common solution is to displace preblast dig line polygons by distances indicated by the BMM vectors. However, studies of BMM vectors show that blast movement not only displaces material laterally but also mixes material internally within the bench (Thornton, 2009a).This paper presents a method for modelling the post-blast muck pile that accounts for displacement and internal dilution using simulated annealing. The preblast ore control block model is re-blocked to 1?×?1?×?1?m sub-blocks. Each sub-block is displaced by simulated BMM vectors conditional to post-blast surface topography and blast initiation sequence data in addition to BMM vector data. The displaced sub-blocks are aggregated into new ore control model blocks whose grades are calculated from the contained sub-blocks. New dig lines are then designed on the post-blast muck pile model using the new ore control block model grades. A case study based on actual data is provided.CITATION:Isaaks, E, Barr, R and Handayani, O, 2014. Modelling blast movement for grade control, in Proceedings Ninth International Mining Geology Conference 2014 , pp 433–440 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 18, 2014

By J F. Colinet, G, J A. Zimmer, R J. Timko

It has long been known that ventilation is a cost-effective method to lower respirable dust concentrations in all types of mining applications. The National Institute for Occupational Safety and Health has been working on a number of different research techniques that use ventilation as a critical component to lower respirable dust levels at surface and metal/non-metal operations in the United States. This article presents five such research efforts. The first research area discusses how improving the ventilation flow patterns in an iron ore mill facility lowered respirable dust concentrations by 31 per cent throughout the primary grinding area. The second research area examines how respirable dust levels were lowered at a dimensional stone shop by using air cleaning units suspended from the ceiling. A third area discusses how improvements in ventilation at underground limestone mines lowered respirable dust concentrations. The fourth area examines how improvements in dust filtration and pressurisation systems significantly impacted the air quality in enclosed cabs of surface mining equipment. The last area presents a newly developed clothes cleaning technique. This technique uses an air spray manifold to blow dust from a workerÆs clothing in an enclosed booth, which confines the dust for capture and removal by a baghouse dust collector. These research areas represent an array of different control technologies to lower respirable dust concentrations. Ventilation is an integral part of these control technologies.

Jan 1, 2005

Excavator output rates given in Makers' catalogues are sometimes based on favourable operating conditions. Mine operators and planners are more interested in the Effective Hourly Output in normal operation (Qe) a plant system can give hour by hour and year after year in a particular application. The number of hours mining plant will be available for normal operation will be less than the annual total of 8760 h. The number of the available hours which can be utilised at Qe will depend largely on the number and types of units in the plant system, the manners in which they are applied and the nature of the deposit in which they work. The emphasis herein is on continuous systems for deep stripping with BWE's as the primary excavator. Examples and suggestions are given for the annual hours at Qe for some BWE systems.

Jan 1, 1981

By Grader F. E

A linear motor properly wound can serve as a mechanism for separating paramagnetic sulphide minerals, like pyrrhotite, from other sulphides and associated gangue minerals. The effective- ness of separation depends on the energising current of the separator, the frequency of the a.c. cycle, and the particle size of the minerals. The speed of travel of the minerals over the surface of the separator is also a function of particle size, and appears to be constant. The movement of pyrrhotite, magnetite and iron filings of comparable size fraction (150um +74pm) on the linear motor surface has been observed using a cine camera. An attempt has been made to give a theoretical basis for the movement of the particles by calculating the minimum electrical energy required to move them. Further, the rate of decay of magnetic moment of the particles has been estimated for magnetite and it has been found that sufficient residual magnetism existed in the particles after they had been exposed to the first half of an a.c. cycle for them to have like polarity with the second half of the cycle. The particles are therefore repelled from the motor surface every second half of the cycle. This repulsion due to remanent magnetism is the probable cause of particle movement over the linear meter surf, e.

Jan 1, 1980

By A P. Wibowo

Indonesia holds a significant role in the utilisation of coal resources in the world. Although the number of Indonesian coal resources and reserves do not fall into the world’s top ten, according to 2009 statistics, Indonesia is the seventh largest producer of coal with a production of 256 Mt. More than 80 per cent of this amount is sold in the export market, making Indonesia the world’s second largest coal exporter. Most of the exported coal from Indonesia is used to fulfil the needs of the Pacific market, such as Japan, Taiwan, China, among others. It is also possible to reach the Atlantic market.Along with Indonesia’s development program, until 2025 the Indonesian government has adopted a National Energy Policy that aims to reduce the role of petroleum in electricity generation and replacing it with coal. As a follow-up of the policy, since 2009 PT PLN, the state electricity company has built steam power plants throughout Indonesia as an implementation of the first stage of the Electrical Acceleration Project with a capacity of 10 000 MW. Moving forward, in 2011 PT PLN will also build the second stage of the project with a capacity of 10 000 MW. As a result of the program, the domestic need for coal is expected to increase as much as 44.8 Mt.With the increase in domestic need and decrease in the number of reserves, the Indonesian government has adopted policies to secure the domestic coal supply. A policy that may potentially be adopted by the government is the limiting of coal production, seeing the high rate of increase in Indonesian coal production. The adoption of such a policy will change the distribution map of coal in the Pacific market. Thus, this paper will evaluate the change of coal distribution patterns in the Pacific market along with the increase in Indonesian domestic needs and Indonesian adoption of policies regarding the securing of coal supplies.

Nov 22, 2011

By M Neurohr, B Wacker, D Mensing, C Murphy, W Kitz

Mining operations have large power requirements. The biggest consumers of energy are the drives for the mills located in the concentrators. Assuming that the decision is made on how many mills are needed and how big these mills will be, it can be determined how these mills should be driven. The decision as to which drive should be applied depends on design limits for different mechanical or electrical drives, anticipated operation modes, capital expenditure optimisation and lifecycle cost optimisation.The task for the engineer specifying the drive equipment is to select a drive solution that can debottleneck the operation, avoid interruption of production and enhance the reliability of the process. At the same time, the engineer must choose a design that enables cost optimisation either in a single investment or in relation to the total cost of ownership (TCO).This paper outlines different mechatronic or electric drive alternatives for tube or horizontal mills applied in the mining industry, along with their advantages and disadvantages. The paper covers a wide range of applicable drive systems and provides a background to the benefit of applying integrated drive systems.CITATION:Wacker, B, Kitz, W, Murphy, C, Neurohr, M and Mensing, D, 2015. Application of different drive systems for horizontal mills, in Proceedings Iron Ore 2015, pp 205–216 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By K Fiedler, A Newell, P D. Munro

Test work is the foundation upon which the success of projects and subsequent operations is laid, reflected in Professor Arthur Taggart’s pithy observation: ‘Make your mistakes on the small scale and your profits on the larger scale’. Indeed, Professor AllanTrench has succinctly noted that ‘Get the metallurgical characteristics wrong and you don’t have a project’.With deposits becoming lower grade, more structurally and mineralogically complex, final products requiring lower levels of impurities and tailings management demanding more attention, test work now assumes even greater significance in the acceptance and successful execution of a project. This paper is the first in a series aiming to stimulate thought on the metallurgical test work process by getting back to the fundamental basics through exploring and providing some guidelines for the metallurgical testing world, noting preferred practices as well as precautions and mitigations. This covers the key characteristics of metallurgical test work programs, including what needs to be done, sample selection, quality control and associated drivers, and most importantly, selecting, assessing and managing test work facilities. CITATION:Newell, A, Munro, P D and Fiedler, K, 2018. Metallurgical test work – between a rock and a hard place, in Proceedings 14th AusIMM Mill Operators' Conference 2018, pp 15–32 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018

By A McCallum, J Abols, G Patrick, G Johansen

The authors challenge the traditional thinking that whole ore cyanidation followed by Carbon in Pulp (CIP) or Carbon in Leach (CIL) should be applied as a standard process in the majority of gold processing flow sheets. The concept of whole ore leaching by using cyanide can result in unnecessary environmental and capital risk. Alternative, currently available technologies can be used to provide the desired level of gold recovery at a much lower installed cost and less impact on the environment. Gravity concentration, alone or in conjunction with flotation, can produce a gold bearing concentrate that can then be fed directly to a batch or continuous intensive cyanidation unit. The In-line Leach Reactor (ILR) is an intensive cyanidation unit developed by Gekko Systems of Australia. Advantages of this technology include significantly reduced capital outlays for greenfield plants or plant upgrades and increased investor returns. Reduction of onsite cyanide and carbon inventories improves plant safety, materials handling and site security. By using direct electrowinning to treat the gold bearing solutions produced by the ILR, the need for a conventional carbon stripping circuit is removed. Potential also exists to increase grind size û saving energy, further reducing capital and operating costs and decreasing the environmental impact of a mill. Detoxification of cyanide before the release of solution to the tailings dam can minimise tailings disposal and containment requirements. When used in the right application the proposed process will have little or no impact on gold recovery and may actually increase recovery for complex ores. Areas applicable to this type of treatment include: plants in environmentally sensitive regions, lower tonnage higher grade deposits, coarse gold deposits, and preg robbing ores û some of which may not currently be economically feasible using standard processes and flow sheets. We have provided two examples of such projects, where an alternative to whole ore leach and CIP or CIL has the potential to deliver these benefits.

Jan 1, 2004

By M Yahyaei, F Vos, J Siliezar

Site-based case studies (including data collected from industrial surveys) and their application in evaluating circuit performance, have a significant role in developing reliable process models. Such models are useful to both plant metallurgists and researchers. Appropriate process models enable the plant metallurgist to assess the impact of different operational parameters on the overall circuit performance. They also provide the researcher with a detailed understanding of process behaviour in response to changes in ore characteristics and process conditions (ie plant throughput, ore competence, ore type). Thus enabling the identification of effective operating factors, and allowing them to be ranked in order of their influence on the process response, which eventually develops into a process control tool in the hands of plant operators.The above approach has been developed and applied at the Julius Kruttschnitt Mineral Research Centre (JKMRC) separately for both comminution and flotation processes. In recent years, the JKMRC has attempted an integrated approach by developing process models that incorporate the impact of upstream processes on downstream processes. This is not possible using the traditional approach of separate comminution and flotation surveys, so conducting integrated plant surveys is crucial for success in developing integrated process models. This paper summarises industrial experience gained while conducting such an integrated plant survey at Glencore’s Ernest Henry Mining operation near Cloncurry in north Queensland. An appropriate approach should be taken to enable the alignment of different requirements from different processes during the plant survey. This, as well as the challenges faced in integrating comminution process models with flotation process models, are identified.CITATION:Yahyaei, M, Vos, F, Powell, M S, Siliezar, J and Perkins, T, 2014. Challenges in developing integrated process models based on industrial survey data, in Proceedings 12th AusIMM Mill Operators’ Conference 2014 , pp 437–446 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 1, 2014

By V S. Vutukuri, K Shariar

This paper present a modification of selected strength criteria for coal and rocks containing weakness planes. The three strength criteria, namely, Murrell (1965), Bieniawski (1974a, 1983) and Hoek and Brown (1980) have been assessed for coal (containing weakness planes) by using triaxial strength tests. Triaxial test results indicated that the strength of coal specimens depends on the weakness plane inclination with respect to the principal stress direction. However it is shown that with increasing confining pressure, the effect of weakness planes inclination on the strength of coal specimens is reduced. The constant parameters in the three failure criteria for coal are determined for each weakness plane inclination by using the Datafit computer program (nonlinear regression analysis) and the results are compared with other rock types.

Jan 1, 1999

At the beginning of the seventies pre- drainage of methane was introduced in West German coal mining in order to reduce the gas emission from the worked seam. After three pilot tests on the "Rheinland" Colliery (86 boreholes in seam "Prasident"), "Bergmannsgluck/ Westerholt" Colliery (23 boreholes in seam "Gustav") and "General Blumenthal" Colliery (27 boreholes in seam "Hugo" and 170 boreholes in seam "Karl") systematic large scale tests with extended investigations were carried out un the "Rheinland" Colliery (127 boreholes in the seams "Anna", "Blucher", Prasident"). During this time an analogous test was carried out on the "Consolidation" Colliery (21 bore- holes in seam "B"). In these studies and tests the technical feasibility, efficiency and economy could be proved, so that pre-drainage of methane starts spreading. On the "Rheinland" Colliery pre-drainage has become common practice in gassy seams. Mainly two points impede a faster spreading of method: 1. in many cases the necessary requirement, that one or both of the gate roads should ire driven 6 to 12 months before the face is worked, is missing. This is mainly due to the difficulty of retreat mining in passe seams.

Jan 1, 1982

By D Tanzil, H Jones

Every mine will close! Charting a profitable course through mine operations to acceptable mine completion requires that risk and opportunity management planning of the mine life begin as early as possible in the life cycle. Management targets and metrics are required to identify and navigate the course to successful mine completion based on economic, social and environmental criteria. This paper outlines the application of The Metrics NavigatorÖ principles to the life cycle of a mine site. In general, metrics are required to make key strategic ideas apparent, transforming those ideas into a manageable set of quantitative measures that guide communication and decision making. For example, the chemical industry has established metrics that focus on the life cycle impacts of its products and eco-efficiency of their processes. Other industry sectors have focused attention on workplace and community well-being outcomes. These management metrics are necessarily organisation-specific, aligned to stakeholdersÆ expectations and the strategic outcomes sought, as well as the cause-and-effect relationships underlying key issues. Recently, the Global Environmental Management Initiative (GEMI), a consortium of multi-national companies, developed The Metrics NavigatorÖ. The guidance document provides a structured process for assessing and developing metrics for key environmental, social, and economic issues based on business and stakeholder perspectives. It incorporates best practices learned from the chemical and other industry sectors and has since been applied to develop metrics that guide life cycle strategies. The paper examines how the life cycle of a mine site could benefit from experiences in other industry sectors where sustainability metrics have guided strategy. It considers the potential application of The Metrics NavigatorÖ process to the life cycle of a hypothetical Australian mine site using the processes that have been successful in other industry sectors.

Jan 1, 2009

By M Brady

"It has long been recognised that the barometer infl uences areas of underground coal mines that havebeen sealed off from the current, or active, mine workings but it appears litt le formal research hasbeen done on how the barometer aff ects the goafstream sample point. Based on statistical analysis of samples from a number of mines from Queensland and New South Wales it can be concluded that there is a direct correlation between the barometer and oxygen concentration at a goafstream sample point. To help mitigate some of the high consequence hazards within the underground coal industry and protect the health and safety of the persons within that environment, many monitoring tools are utilised. A control recognised in management plans prescribed under New South Wales and Queensland legislation is the need to conduct monitoring to identify the early warning signs of spontaneous combustion. One of the monitoring tools utilised involves a bagsample being collected from a goafstream sample point then returned to the surface for analysis.When the sample is incorrectly collected, the resultant analysis from a gas chromatograph provides litt le value to the persons charged with the obligation of operating the coal mine at an acceptable level of risk. This, therefore, increases the probability of spontaneous combustion leading to a loss of equipment, mine and in the worst case, life. When the sample is collected correctly, the analysis presents early warning signs of low level oxidation allowing corrective action to be taken, to prevent the oxidation accelerating to spontaneous combustion. The eff ect the barometer has on this sample point should be recognised and the knowledge imparted to persons who conduct sampling to remove a variable in the bag sample collection process. This will ensure the persons operating the mine have a bett er understanding of what is happening within their longwall goaf."

Jun 1, 2012

By B Tutmez

Determination of stress-strain behaviour of rocks plays a crucial role in understanding the response of rocks during loading. However, it is a tedious, expensive and a time-consuming process to obtain such characteristics both in the laboratory and in situ. On the other hand, non-destructive testing methods such as ultrasonic velocities can produce a reliable and fast solution to indentify state of strain and stress in rocks. The present paper aims to provide insight into the relations amongst ultrasonic wave velocities, amplitudes and deformability properties of porous siltstone under compressive loading. For this purpose, pulse (vP) and shear wave velocities (vS) along with amplitudes (AP - AS), and applied loads with resultant strain were measured simultaneously so that response of siltstone to compression can be evaluated. In addition, initial vP and vS were recorded at the beginning of each test to calculate dynamic elastic properties of the specimens. This provided a comparison between static and dynamic elasticity properties of siltstone. Crack damage associated with the onset of dilation was also investigated. The results showed that there is a non-linear logarithmic relation between velocities and stress-strain level for siltstones.

Sep 26, 2011

By S Amor, A Beasley

This paper provides an example of how industry can respond to the implementation of new regulatory approaches to mining risk, health and safety by adopting a robust, practical, software-based approach to the management of risk accountabilities in terms of competence, experience and suitability for obligations and responsibilities, as required in Queensland Coal Mining operations due to the introduction of Recognised Standard 22 (‘RS22’; Resources Safety and Health Queensland, 2021). Based on the authors’ experience from working with several Qld mine operations, it offers a snapshot of the experiences, approaches and reservations faced collectively by industry as a result of the introduction of RS22. Several challenges exist within the detail of RS22, leading to varied interpretations, implementation strategies and overall compliance between mine sites. Arguably the single biggest challenge identified has been how to find a balance between compliance and practicality – considering cost, operational interruption, available pathways for delivery of competence, ongoing compliance and value adding to the business operations and people. Software-based solutions are increasingly being relied upon to address the introduction of new regulatory approaches and the significant administrative load placed on mining operation Site Senior Executives (‘SSE’) due to RS22 means this case is no different. This is further complicated given the continuous, ongoing changes with the site management structure witnessed by the authors across each of the mining operations as a result of continuous changes to personnel, the site risk profile and an overall mining industry uncertainty of how to respond to RS22. The stringent reporting/notification requirements under legislation compounds this further. The approach put forward by the authors is a well-considered rationale and approach to the application of training and skilling; and equally how to ‘future proof’ the coordination of site training needs around changes to the Management Structure, the Risk Register, skilling processes and succession planning. A brief investigation of other legislative frameworks concluded this approach would likely meet or exceed expectations of jurisdictions across Australia and overseas, making this a highly flexible approach for establishing a competent Management Structure to provide safe systems of work.

Apr 16, 2024

By R Ballantyne, M Adams

Time Usage Models, used as a basis for calculating performance indicators for mobile mining equipment, have developed from very simple to very sophisticated models. This development has paralleled the increased collection and analysis of production data that itself has been enabled by the evolution of underground voice and data communications along with the relevant information systems. A Time Usage Model divides the hours that equipment is (or is not) used into standard components, by a hierarchical breakdown, so that measures of productivity can be used to compare performance of both people and equipment. The calculation of equipment availability, and thus the underlying Time Usage Model, has always been an extremely emotive topic as different groups use time usage information for different purposes. The direct link between measuring performance Key Performance Indicators (KPI) calculated from these models and employee rewards impacts upon the workforce. This paper discusses the conflict in use by various stakeholders and proposes ways to address some of the more contentious issues each supported by case studies. The simple status code functionality used by early systems has proven inadequate, leading to the evolution of “work-arounds”. These workarounds have become the norm and unfortunately have become embedded in the next generation of models and the information systems that incorporate them. This paper contends that the industry should stop building Time Usage Models to accommodate shortcomings in proprietary systems, but rather collaborate with suppliers to develop innovative methods to deal with the fundamental requirements. There are many points of differentiation that are not clear-cut. Pitfalls are discussed as well as threats to success. A framework of rules is developed as guidelines for how a Time Usage Model should be developed and applied. This will hopefully stimulate the on-going discussion as to how Equipment Availability and other components of the model should be calculated.

Mar 15, 2021

By J Joy, D Griffiths, A Bye, G V. Kizil

Poor standards of electrical installation and maintenance continue to contribute to electrical related fatalities and injury risk in the mining industry. Electrical isolation has the potential to initiate major unwanted events (MUEs) and as such requires thorough analysis to demonstrate adequate management. There have been 719 incidents related to accidental contact with electricity over the past five years in the Queensland mining industry (Queensland Government DME, 2012a, 2012b) with the last fatality being recorded in 1997 (MESA, 2012).A project funded by the Australian Coal Association Research Program (ACARP) has developed a form of a safety case using the four-layered æCoal Mine Safety Regime (CMSR)Æ approach. The CMSR is transparent and robust as it includes full site risk assessment and special issues risk assessment to be demonstrated as part of the process.The practical application of the CMSR has been demonstrated using a longwall mining case study site, where a unique 11 kV armoured face conveyor (AFC) is in operation. The case study has involved progressive application of the requirements of each layer of the CMSR (see Figure 1) to high voltage (HV) electrical isolation related issues. The project has specifically concentrated on understanding and analysing two high priority MUEs, electric shock and unplanned movement of equipment, through Layer 1 analysis. These two MUEs are an important part of the project as they have demonstrated the steps that may be taken to satisfy the risk management processes at Layer 1 of the CMSR and have contributed to resolving issues at the other three layers of the CMSR.The analysis of HV electrical isolation has been used as an exemplar to demonstrate the CMSR process and its practical application. The CMSR is applicable to major/principal hazards management as identified by the New South Wales and Queensland jurisdictions.This paper provides an overview of the development of a form of safety case using the CMSR and introduces the case study application for HV electrical isolation risk management at underground coal mines focusing on the major unwanted event of electric shock.This project provides the mining industry with a documented, publicly accessible, form of safety case using the CMSR approach for the first time.CITATION:Kizil, G V, Griffiths, D, Bye, A and Joy, J, 2012. Using a coal mine safety regime approach to the management of high-voltage electrical isolation, in Proceedings International Mine Management 2012, pp 59-74 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 20, 2012

By K Katov, S T. Ciutina, J D. Pyke

The development and optimisation of mill discharge trommels, and specifically their screen panels, can be a neglected area in the complex operation of a minerals processing plant. Trommels are often seen as a ‘set and forget’ component of the circuit, even when significant improvements in design are possible. A redesigned trommel and panel arrangement has simplified and added flexibility to the plant shutdown schedule at Kirkland Lake Gold’s Fosterville Gold Mine in Central Victoria.Prior to the trommel redesign, the shutdown frequency was determined by the expected life of trommel panels at 14 weeks. Planning downtime around this item led to higher maintenance costs and wastage in other areas of the plant. This was particularly disruptive with respect to mill lining change-outs, which were forced out of sequence and often changed prematurely. Fosterville Gold engaged Metso Australia Limited to propose a new trommel design that would better suit the site. The new trommel was engineered to balance simplicity with performance, and incorporated the latest in Modular trommel design, modelling and Finite Elemental Analysis (FEA). Modular Panels and Spiral Segments achieve significantly longer life, and allow in-situ panel change outs, flexibility in spiral and dam positioning and an improvement in classification performance. Trommel panel life has significantly increased from 14 to 71 weeks in the trommel’s highest wearing zone. The new design has eliminated some risks to safety by reducing manual labour and lifting requirements during shutdowns. There is greater flexibility with respect to shutdown requirements. The site is no longer at the mercy of trommel panel lifespan, which allows for better optimisation of wear components in the circuit. CITATION:Pyke, J D, Katov, K and Ciutina, S T, 2018. Modular SAG mill discharge trommel for maintenance flexibility and performance, in Proceedings 14th AusIMM Mill Operators' Conference 2018, pp 613–620 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018