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By Gillies A. D S

Rail, port and shipping charges represent 30 to 50 per cent of landed costs for Australian coal mines selling to Asia. This proportion is higher for sales to Europe, yet it is in Europe where Australian producers are aiming for increased market share. The landed cost of coal to the international customer is the key parameter which determines market competitiveness. The objective of this study is to examine Australian export coal competitiveness in terms of transport distance. The approach used examines world coking coal and steaming coal production and the transport distances between major exporting regions and importing countries. Reference is made to the importance of land transport costs and a comparative approach for emphasising the relative magnitude of this factor is developed. Models developed are examined in terms of Australia's exports and a conclusion is reached that a reduction in rail freight costs would be an effective measure for improving the competitiveness of Australia's coal industry.

Jan 1, 1994

By B Broad

"Establishing ventilation in the early stages of a new mine is an essential step to achieve scheduled outcomes that ultimately drive the financial success of an operation. If the primary ventilation is not in place in time to support a contractorÆs work output, then the ore delivery is likely to be severely impacted. Options to increase ventilation in order to address shortfalls are limited. This in turn can lead to reduced revenue generation at a time when a mine is at its highest capital outlay. This can have implications for any company, but even more for an explorer moving to producer. The ventilation put in place to cover the start-up period is also unlikely to cover any extended or increased load required to meet schedule delays.The following paper examines two issues in relation to ventilation with a focus on small to medium projects where the company is establishing a mine using a mining contractor. The issues being: potential impacts on the contract and tender process when using a mining contractor key mine design considerations, such as æcrunch timeÆ, as they interact with ventilation achieving a successful ramp up.A recommendation is made for higher levels of detail around secondary ventilation leading up to the primary fan installation. The information should be included as part of the tendering process and preliminary project execution planning. Understanding the æcrunch timeÆ concept can lead to strategies, as well as back up plans, to minimise any negative impact.By understanding key risks around primary ventilation establishment for a new mine, detailed design work can be completed where it is needed most. Value is added by reducing uncertainty and a payback with better contract terms and a more robust ramp up plan. This will improve the economic return for the company and reduce the risk.CITATION:Broad, B, 2013. Contract considerations and other critical ventilation aspects in achieving a new mine ramp up, in Proceedings The Australian Mine Ventilation Conference, pp 207-214 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jul 1, 2013

By D Yan, D Connelly

Beneficiation of magnetite is an integral part of the future of iron ore processing. Historically, the focus of Western Australian producers has been on exporting direct shipping ore (DSO) namely haematite. The future for new DSO resources is limited so companies are changing their emphasis into processing the very large, undeveloped magnetite ores in Western Australia (WA), using beneficiation to produce shippable magnetite concentrates. These magnetite resources require higher cost processing techniques such as fine grinding and beneficiation to produce saleable concentrates. This distinct difference, from the DSO ores, has led to the development of a number of new technologies. This paper reviews: the different techniques used for magnetite beneficiation and provides some case studies in the WA industry; the use of mineral liberation analysis (MLA) to describe the nature, grain size, occurrence and associations of the mineralisation;the consideration of coarse cobbing as a critical upgrading; the application of high pressure grinding rolls (HPGR) to save energy; how the field of magnetic separation has resulted in new machines with higher field strength (SLon Separators); ultra fine grinding requirements of magnetite concentrates; andthe application of reverse flotation to reduce silica in the concentrates.

Jan 1, 2009

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 G A Brown

Environmental legislation is changing rapidly throughout Australia at the present time, and with that change comes additional responsibilities for the mining and petroleum industries. Among the many changes that are being made are increased penalties for both criminal and accidental environmental impairment. The defences for criminal offences are limited and for other offences the laws may impose strict liability - in effect the offender is guilty until proven innocent. Mines may be included under contaminated land legislation, creating additional liabilities for clean-up, rehabilitation and long-term management. It is not unknown in Australia for the value of a mortgaged property to be less than the amount of the environmental liability acquired by a mortgagor in possession due to contamination of the site. An essential part of the management program for resource projects is now the regular conduct of an environmental audit, the results of which assist in the management of the legal and financial liabilities facing company directors and managers. The audit can also assist with negotiations with government agencies, staff, unions, insurers, Aboriginal and other community groups. An environmental audit may also help to ensure that companies are claiming the maximum allowable deductions for environmental works under the tax laws, and provide evidence in support of such claims. Environmental legislation affecting resource industries Environmental legislation in Australia is changing rapidly and can impose massive constraints, substantial administrative costs, and considerable liability on directors, managers and the corporation. Pollution control legislation Every State and Territory of Australia has a range of pollution control legislation contained in either individual acts relating to air, water, noise and land, or embodied in a single environment protection act. Pollution control legislation provides a critical management baseline for resource industries throughout Australia, often requiring the full-time attention of an environmental manager or an environmental department. In general, it is an offence to discharge effluents into water, or emit gases into the atmosphere above prescribed limits, cause noise above a regulated level, or contaminate land without a licence. A licence determines how much of a substance can be discharged, the location, the receiving environment, the quality, and the time at which discharges can be made or noise can be caused. Planning legislation Planning legislation controls where a project is located, how it will be constructed and operated, how large it is allowed to be, and what will happen once the project is completed. Development consents or approvals will generally contain a range of conditions controlling the preparation of the site, the construction of the facility and the way it is operated throughout its expected life time. Resource projects may be regarded under legislation as scheduled or designated developments requiring special treatment during the decision-making process. Under planning legislation, it is usual for resource projects to be subject to an environmental impact assessment process. Resource legislation Resource legislation specifically covering mining and petroleum in Australia, also contains requirements regarding protection of the environment during exploration for and extraction of minerals and oil. A mining or petroleum production lease usually contains numerous conditions regarding protection of the environment and rehabilitation of the site during and after the life of the extractive process.

Jan 1, 1994

TSL Concepts and Practical Examples of the Non-Reactive System - Meyco TSL 865 Thin Spray-on Liners (TSLs) have been intensively investigated by mining and chemical industries within the last decade. Apart from the basic concept of spraying thin liners, expectations of the product's performance vary, eg immediate active strata support is seen as a key to control the ground permanently. For many coal mines this is an important factor to reduce maintenance in their roadways and enable permanent production from the long wall. In opposition to a passive mesh system this technology offers immediate active support to the strata. But not only coal mines are interested in TSL technology, there are potential applications in hard rock mines, during shaft sinking, pillar support and as an anti-weathering sealant. This paper will explain the advantages and disadvantages of TSL concepts; it will give examples of successfully applied TSLs with a main focus on the non-reactive and flexible system MEYCO TSL 865 by BASF. Furthermore, it will indicate the limitations and discuss briefly the bearing capacity and reasonable lab testing of such systems.

Nov 25, 2010

By A Halim

"There is still debate about who should ultimately be responsible for the ventilation system in anunderground mine. The Queensland Coal Mining Safety and Health Regulation 2001, states that adedicated ventilation offi cer is the person, while Western Australian Mines Safety and InspectionRegulation 1995 states that it is the mine manager who is responsible; the ventilation offi cer actsas the managerÆs principal ventilation advisor. This paper outlines a comparison between bothapproaches."

Jun 1, 2012

By J W. Muir, N Bedford

Hong Kong is one of the most rapidly developing cities in the world. With constant population growth and limited opportunities for space, the development of a fast and effective underground public transportation network is essential. Hong Kong’s Mass Transit Railway (MTR) Corporation is currently undertaking several large underground expansions to its existing network. Much of the excavation will be carried out using the drill and blast excavation method.Drill and blast excavation is common in Hong Kong and with the continued development of underground infrastructure the use of the drill and blast excavation method will increase. Although an effective method of excavation, the blasting vibrations caused during construction can have an adverse impact on surrounding structures and impose disruption on the local community.In order to minimise the risks associated with blasting vibrations, and to demonstrate that the impact on local stakeholders will remain within acceptable limits, it is generally necessary for a contractor to submit a blasting assessment report for approval by government authorities before blasting may commence.Continued increases in population density will force more infrastructure to be constructed underground. Tunnels and caverns are increasingly excavated in closer proximity to critical sensitive receivers. This leads to greater potential impacts on the community, tightening constraints on contractors and a higher level of confidence required for approval authorities. Finding a balance between the needs of the community and rising construction costs becomes more challenging.This paper presents a case study on how the blasting assessment report process has been successfully implemented for a major MTR project situated in a densely developed area of Hong Kong. It describes several methods of assessing blasting vibration impacts, innovative uses of blasting for excavation and the mitigation measures employed to provide the best outcome for all project stakeholders.CITATION:Bedford, N and Muir, J W, 2014. Blasting vibration assessment and innovative blasting methods in high-density urban environments, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 9–20 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By J Zhang, L Klemettinen, A Jokilaakso, J Biswas, J Partinen, H O’Brien, A Klemettinen

Waste lithium-ion batteries (LIBs) are important secondary sources of many valuable materials, including Critical Raw Materials (CRMs) defined by the European Union (EU): lithium, cobalt, manganese, and graphite. Additionally, LIBs typically contain nickel and copper, which are classified as Strategic Raw Materials for EU since 2023. In recent years, great effort has been made to develop efficient recycling processes for waste LIBs. Pyrometallurgical processes have been essential in industrial production of metals for many decades. These technologies are relatively mature, with high adaptability for different raw materials. Pyrometallurgical treatment in LIB recycling typically involves the use of smelting processes, in which waste batteries are heated above their melting points and metals are separated through a reduction reaction in the liquid phase. Through this recycling route, cobalt, copper, and nickel can be efficiently recovered in the form of a metal alloy, whereas lithium and manganese are lost in the slag phase. The goal of this work was to increase the recoveries of valuable battery metals through a combination of hydro- and pyrometallurgical unit operations. First, industrial Li-ion battery scrap underwent a selective sulfation roasting stage, where the aim was to transform LiCoO2 and Mn-oxides into Li, Co and Mn sulfates. After roasting, the battery scrap was leached in distilled water with a solid to liquid ratio of 100 g/L at 60°C and recovered 95 per cent of Li, 61 per cent of Mn and 35 per cent of Co. After leaching, the solid leach residue was mixed with industrial Ni-slag and biochar, followed by reduction at 1350°C in argon atmosphere. The high-temperature smelting experiments were conducted as a function of time (5–60 mins) to investigate the reduction behaviour of battery metals. The results show that Co and Ni from the slag and leach residue can be efficiently recovered in the slag cleaning stage.

Jun 19, 2024

Economic recovery of valuable natural resources is enhanced through an integrated approach to establishing and operating the mine.Gordonstone has a unique and valuable high quality coal and the basic aim for the mine is to satisfy customers through high standards of safety, productivity and reliability and genuine regard for its people.Gordonstone defined its main resources available for recovery of its natural resource and has designed and built facilities which display technical and engineering excellence.But to build a world class mine Gordonstone recognised the need to take a large- step beyond relying on technical excellence. In designing Gordonstone mine all aspects of coal mining were treated as part of an integrated process.This paper will explain the route Gordonstone has taken and will continue to take into the future in using an integrated approach to mining.

Jan 1, 1993

By P A. Grossman, J H. Rubinstein, M Brazil, D Whittle

Many ore reserves are harvested by a combination of open pit and underground mining methods. In these cases, there is often material that could be mined by either method, and a choice has to be made. The area containing this material is referred to as the transition zone. Deciding where to finish the open pit and start the underground mine is referred to as the transition problem and it has received some attention in the literature since the 1980s.In this paper, we provide a review of existing approaches to the transition problem encompassing: graph theory-based optimisation employing an opportunity cost approach, heuristics and integer programming. We also present a novel opportunity cost approach, that takes into account a crown pillar, and show how the new approach can be best applied through the unconventional application of an existing mine optimisation tool.CITATION:Whittle, D, Brazil, M, Grossman, P A, Rubinstein, J H and Thomas, D A, 2016. Determining the open pit to underground transition – a new method, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 731–742 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

In the past two and a half years, over 40 000 metalliferous mining and related services personnel have been trained through an Australian Generic Safety Induction system. This is almost half of AustraliaÆs metalliferous mining related workforce. This remarkable industry acceptance and delivery of safety courses is supported by Acacia Resources, Great Central Mines, Homestake, Newcrest Mining and WMC Resources, amongst hundreds of other mining, exploration and major contracting and services companies. MARCSTA; the Mining and Resources Contractors Safety Training Association (a pro-active not-for-profit self-help group of 24 major contracting companies) developed this generic safety induction. MARCSTA set out to find the æcommon groundÆ necessary to help address the evident safety problems and cost of re-training that were plaguing development of an internationally competitive and productive export industry. The incredible expansion of Australian mining during the decade fuelled a need for out-sourcing, resulting in much larger numbers of contractors on-site. At the same time, changes within Australian legislation, community expectations and the development of huge fly-in/fly-out operations and widespread skills shortages led to a rapid labour turnover and a higher paid workforce. Many Australian mining houses also ran international operations, particularly in South East Asia and head hunted people across the world. The skill levels fluctuated and fell at some local operations. Employers could no longer rely on systematic in-house training of permanent employees to improve safety and productivity as workers could and often did move on. Serious discrepancies in both quality and quantity of safety induction training and work practices occurred. Repetitive, boring and ineffective safety training became an embarrassing and costly burden for companies and workers alike. Then a spate of mining deaths sparked highly publicity, workforce concern and a demand for improvement from government, unions and corporate stakeholders. MARCSTA recognised it had to develop a high-quality safety-training program to satisfy the needs of all employers and be acceptable to others within the industry. This induction system had to be flexible enough to meet differences in legislation between states and industry sectors and be portable to enable cost and time savings for the new transient workforce. Changes in the last two years as a result of evaluating and incorporating various Taskforce inquiries into underground mining fatalities later led to the development of the MARCSTA Underground Safety Induction. This logical development added to the run away success of MARCSTAÆs General Safety Induction and was seen to be essential for many surface mines that were planning to develop underground operations. There are many lessons that MARCSTA learnt during its development that Pacific and South East Asian mining operations can benefit from. The most important of these are the support of stakeholders within industry and the recognition of higher safety and health expectations from workers and government. This goes hand-in-hand with the productivity and return on investment expectations of companies and their shareholders.

Jan 1, 1999

Mechanical and electrical (M&E) systems in road tunnels are constrained by the traffic envelope and the construction profile. Whilst these spatial constraints are often ælocked inÆ early in the design process, the detailed M&E design continues for some considerable time after key civil engineering issues have been resolved. Ventilation design criteria for both normal and emergency operation often involves considerable negotiation with a wide range of stakeholders. Final system performance and spatial requirements are only finally resolved when suppliers are selected following the tender process. Lighting design is dependent upon a wide range of factors including tunnel lining materials and associated colours as well as agreed maintenance regimes. Cabling systems can only be developed when the general arrangement for power distribution is agreed and a system of substation, switchrooms and equipment rooms is in place. Many other systems such as fire protection and communications facilities fill the available space beyond the traffic envelope, where physical, structural and æsight lineÆ requirements must all be accommodated. The more co-ordinated civil engineering and M&E design is and the earlier the process starts the better the outcomes for all parties.

Jan 1, 1999

By J Jackson, K Nguyen, A Nguyen, E Manlapig

"With the recent advancement in drill core imaging systems, a large volume of high resolution drill core images can now be rapidly collected and mineralogically classified. This paper introduces a novel semi-automated method for rapid prediction of process engineering parameters from this type of image. The aim is to allow for a rapid and low-cost assessment of the ore processing variability within a mineral deposit with a reduced amount of metallurgical test work. This method will see its application primarily in the project evaluation phase, where proper evaluation of the processing variability of the orebody normally requires a prolonged and costly metallurgical test work program. Applying this image-based texture analysis method on the mineralogical classified drill core images, the ores are classified according to their textures. For each engineering parameter, a small number of physical test work is required to produce a data set for training and testing of the predictive model. The paper also presents a case study in which this method has been applied to predict the A*b parameter used in mineral process plant design.CITATION:Nguyen, A, Jackson, J, Nguyen. K and Manlapig, E, 2016. A New Semi-automated Method to Rapidly Evaluate the Processing Variability of the Orebody, in Proceedings The Third AusIMM International Geometallurgy Conference (GeoMet) 2016, pp 145–152 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jun 15, 2016

By B W. Ham

The legacy of underground coal mining may be a land surface which, in parts, may be unstable in the long term. A case study analysis has been undertaken to explain some of the hazards and how the risk may be assessed and managed.The Ipswich Coal Measures were extensively mined with shallow underground workings, which now underlie a number of suburbs in the eastern side of the city of Ipswich in south eastern Queensland. The area was subject to underground mining from the 1840s to 1997. In general, the mines were small, family-owned operations that were restricted by complex geology, interactions with neighbouring operations and ownership of surface facilities. The oldest available mine plans date back to the late 1890s.The residents in these mining areas have a long history of unexpected mining subsidence events. A level of risk management for property owners has been implemented by the Ipswich City Council, which requires a mining subsidence risk assessment to be submitted as part of building applications for property development in the areas suspected of having mining subsidence risk. This discussion examines a series of generic subsidence events and how the risk may be assessed and managed and the hazard controlled.CITATION:Ham, B?W, 2014. The legacy of underground coal mining – mine subsidence: Ipswich coal measures case study, in Proceedings Life-of-Mine 2014 , pp 113–120 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

By A Karrech, E Hamdi

The uncertainty of geomaterials properties is commonly encountered in resource engineering applications, especially in mining engineering where the rock mass texture, joints, fractures and damage zones can impose the mining method and operation cycles. In the present research work, we focus on the elastic properties of rock masses. We use stochastic numerical simulation of fractured rock masses to estimate their Young moduli. The procedure starts with field mapping campaigns which are conducted to evaluate the locations, dip angles, strike and trace lengths of pre-existing fractures. We develop statistical law parameters of the natural fracture network to represent the weakness patterns. In addition, we use HLA-Dissim, a recently developed and validated Matlab program, to simulate the propagation of monochromatic longitudinal waves and derive the equivalent elastic modulus of fractured rock masses. Such procedure applies within a simulation domain, which is greater than an Elementary Representative Volume.At a second stage, we conduct finite element simulations to validate the previous approach. The matrix and the actual fractures zones are reproduced in the model to mimic the natural set-up. The block is excited on particular positions and its response is evaluated on predefined spots. Real field rock fracture mapping data and monitored single-hole blast induced vibrations are used to validate the theoretical and numerical approaches discussed herein. Comparison between the simulated and measured vibration records shows a great agreement which confirms that the proposed methodology has a full potential to predict and optimise multihole/multidelay blast-induced vibrations.CITATION:Hamdi, E and Karrech, A, 2015. A methodology for rock mass characterisation to control blast-induced vibrations, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 89–96 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By M Stephens, T A. Sutra

Currently, there are several open pit mines with production rates of about 200 000 tpd of ore that are reaching the end of their economic lives. In most cases, the remaining orebody extends to depths greater than 300 m below the pit limit, leaving hundreds of millions of tons of reserves that can only be recovered by means of an underground mining method. One such method used for mass production is block caving. This paper presents a ventilation system for a four-zone block cave mine operation developed on a footprint 1000 m wide and 1200 m long. The system is designed for a mine with a nominal production rate of 120 000 tpd of ore using diesel powered units on the production and reduction levels. It discusses the air quantity requirements for the worst case scenario, which is anticipated to occur five years after the mine has reached its full production capacity. Finally, it summarises the results of computer modelling exercises that were carried out to determine an economic ventilation infrastructure that includes shafts, drifts, main fans, and ventilation control devices.

Jan 1, 2005

By M Schaffer, T Kewe, N Moffatt

Porgera mine is 95 per cent owned by Barrick Gold Corporation. It is located at an altitude of 2200–2700 m above sea level in the Enga province of Papua New Guinea and produces approximately 460 000 oz per annum with a proven and probable reserve of 6.2 Moz. The refractory ore is ground in a conventional semi-autogenous grinding and ball mill circuit. After the gravity gold is recovered, the slurry is floated, oxidised in the autoclaves and then leached. This paper will focus on the flotation circuit and the recent upgrade of the control system. The five interdependent flotation circuits were challenging for operations to control as they dealt with variable grade, throughput and circulating loads, as well as the physical limitations of the equipment. With the installation of 18 Portage Froth Characterization® (PFC) cameras, the plant’s operation has been converted from a level-control based strategy that was focused on individual cells to one that targets grade and recovery control across the entire circuit. Variability in feed and the corresponding launder issues were addressed with a unique site initiative of deflector plates to indicate filling level. Non-linear closed loop control was implemented directly in the DeltaV Distributed Control System (DCS) using Portage Advantage Regulatory Control (PARC) algorithms and optimised with AwaRE advanced controllers. The most noticeable benefits achieved with the upgrade include improved flotation gold recovery, consistent flotation sulfur grade and autoclave performance. Correspondingly, there was a significant drop in boiler diesel fuel usage and launder overflow conditions.CITATION:Kewe, T, Moffatt, N and Schaffer, M, 2014. Porgera flotation circuit upgrade and expert system installation, in Proceedings 12th AusIMM Mill Operators’ Conference 2014 , pp 345–356 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 1, 2014

By M Sandy, P Bamford

The Challenger Gold deposit was discovered in 1995 by Dominion Mining Ltd in a remote western area of the Gawler Craton in South Australia. Mine development commenced in 2002 with initial production from an open pit supplemented by ore from a very small adjacent auxiliary pit. Development of the underground mine commenced in 2004. The orebody plunge of just less than 30 degrees requires careful attention to mine design. Production from the M1 orebody, with less than 800 ounces per vertical metre (ovm) and very limited æsurgeÆ capacity, requires careful scheduling and implementation to ensure continuity of ore feed for milling. Initial production results from underground stopes included more dilution than anticipated. The narrow, high-grade zones proved to have much more complex geometry than early interpretations had indicated. Greatly improved understanding of the mineralisation controls resulted in important changes being made to the underground mine design and method. Coupled with careful control of development and drilling and blasting practices, this resulted in an immediate reduction in dilution and high recoveries of the resource. The benefits of these changes flowed through in the 2005/06 financial year, resulting in a 150 per cent increase in gold production to 108 080 oz and a sharp reduction in cash operating costs to A$280/oz. This was followed in 2006/07 with production of 108 91 oz of gold at an operating cost of $309/oz and in 2007/08 with 109 326 oz of gold at $367/oz. Production to June 2008 has been mainly from the M1 orebody, with the lowest stoping to date on the 580 m Level (615 m below surface) above development mining on the 520 Level. The rate of vertical advance of mining this orebody has averaged 150 vertical metres per year. The increased current combined JORC compliant resource and reserve position of over one million ounces, now includes the M2 and M3 orebodies with a current total average gold inventory up to 1400 - 1500 ovm. Exploration has intersected other shoots and all shoots are open at depth. The adjacent M2 and M3 orebodies are being developed for stoping. The narrow width of these zones from 1 m up to 4 m will require continued focus on ore zone definition, accurate development and careful drill and blast practice. In addition, to minimise cost increases in the current period of rapidly escalating labour, equipment, consumables and energy costs, high productivities will need to be maintained to allow the established rapid mining advance to continue at low unit costs.

Jan 1, 2008

By E Amini, N Beaton

Application of ore pre-treatment technologies such as Grade Engineering and in-pit ore treatment require comprehensive analysis to show proven value is being generated by switching away from the current practices. Considering most mining operations last several decades; the pre-treatment technologies must be investigated over life of mine (LOM) to truly show value was generated or lost. Therefore, a value chain flowsheet model has been usually developed to run those analysis/simulations over LOM using a set of defined ore characteristics and the operating equipment capacities. The Integrated Extraction Simulator (IES) has been used for this type of LOM simulations as it has the necessary flexibility to accommodate the whole mining value chain flowsheet in one platform and provide essential computation power to run mass simulations for the given scenarios using the resource block model. This allows to forecast the value chain response over the LOM for all given scenarios in a feasible amount of time. The traditionally developed flowsheets for the analysis/simulations are usually limited to the mineral processing plant and were developed based on a single audit conducted on the plant in a very short time, e.g. several hours. The process plant is being operated with a certain ore at a certain condition during the short audits which would not reveal the true capacity of the operation equipment when ore characteristics changes. Therefore, it would be impossible to define the true capacity of the equipment and identify the constraints along the value chain. In this study, a methodology was developed to identify the constraints along the value chain and implement those in the IES flowsheet using process information. Also, the equipment models were fine-tuned to represent the true capacity of the equipment in the flowsheet using the same data set. The methodology was tested over five process plant in two operations and showed the performance forecast was significantly improved over the traditional methods being used so far. Then those high-fidelity flowsheets were used to evaluate the ore pre-treatment technologies proposed by the relevant resource company experts.

Nov 10, 2020