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The Kiirunavaara apatite-magnetite orebody is about 4 km long and approximately 100 m thick sheet-like body, which lies roughly in a north-south direction and dips from the horizontal plane along its entire length, in towards the town of Kiruna. The origin of this orebody has been a matter of controversy, with both magmatic and hydrothermal origins proposed. Traditionally and for practical purposes this rich apatite-magnetite ore has been divided into two main types: low phosphorous ore (B-ore) and high phosphorous ore (D-ore). Further the low phosphorous ore is divided into the low alkali (B1) and the high alkali (B2) ore.

Jan 1, 2006

By S F. Rogers, K Doumis, J H. Graaf, B J. Barsanti

Advances in technology now allow geotechnical practitioners to better describe the properties and variability of a rock mass through advances in surface and underground mapping, borehole technology and geophysical imaging. Yet the way in which practitioners use this data is not being realised to its full potential and the quality and quantity of data that is collected is often superior to the conventional design approaches that are typically adopted. A discrete fracture network (DFN) approach provides the ideal basis for using this data to generate geologically-realistic rock mass models based on parameters derived from field data, which more effectively capture the variability and rock mass behaviour. However, until recently, the DFN approach has mainly been applied to cave mining and small-scale models associated with synthetic rock mass modelling or groundwater flow modelling for the nuclear waste and oil and gas industries.Ground support design for blocky rock masses in Australia is often dealt with in a rather traditional manner, adopting either an observational empirical approach through rock mass classification systems or conventional wedge stability analysis techniques. Using these methods requires several generalised assumptions about the rock mass fabric and excavation geometry. As such, the support system is often designed for a worst-case scenario based on a predetermined risk tolerance that the mine is willing to accept and a design block size that is generally determined by the proposed excavation dimension.A study by Doumis (2014) used conventional wedge stability analysis and the probabilistic key block analysis software JBlock (Esterhuizen, 1996) to estimate potential block sizes and support requirements. A DFN approach has also been adopted at Callie underground mine using FracMan™ software (Golder Associates, 2014). The methodology of the DFN wedge analysis will be compared with the key block analysis work undertaken by Doumis.CITATION:Graaf, J H, Barsanti, B J, Doumis, K and Rogers, S F, 2014. Towards the implementation of discrete fracture network modelling as a geotechnical design tool – case study of callie underground mine, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 399–408 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014

By J Zanganeh, M Ajrash, B Moghtaderi

Application of thermal oxidation is considered a promising technique in reducing fugitive methane gas from ventilation air methane (VAM). A typical thermal oxidiser operates with diluted methane and converts it to less potent greenhouse gases. However, having a thermal oxidiser in the vicinity of the coalmine exhaust shaft is a major safety concern as its high operation temperature increases the likelihood of accidental fire and explosion. The aim of this study is to investigate the application and effectiveness of side venting technique in reduction of deflagration consequences caused by methane gas. To address this importance a series of experiments were conducted on a detonation tube designed and fabricated as part of larger scale VAM Abatement safety project. The experimental work was carried out into two stages: examine the flame and explosion properties in a large-scale detonation tube to get reliable data; and then design and employ a venting system into the detonation tube to verify the effectiveness and performance of the venting against the flame and explosion.Results corresponding to this study show that the side vent duct with venting coefficient magnitude of 37 had a significant influence on methane flame deflagration and the explosion characteristics. The maximum pressure rise at the detonation tube reduced approximately 20 per cent to 32 per cent by applying the side venting duct. Also, the data shows that the venting damped the pressure oscillation after the flame deflagration which eventually reduced the system instability. Finally, by applying the venting technique the expected level of damage due to the dynamic pressure reduced to the level of limited building damage.CITATION:Ajrash, M, Zanganeh, J and Moghtaderi, B, 2017. Application of side venting technique in mitigation of methane – air explosion and flame deflagration in ventilation air methane, in Proceedings Australian Mine Vent Conference 2017, pp 153–258 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

By P Luo, J E. Danoczi, P Nakutnyy

Sensor-based sorting methods to remove waste or for upgrading ore prior to downstream metallurgical processing is becoming more prevalent for mining operations. X-ray transmission (XRT) sorters are a popular choice for mineral processing plants since they can sort a wide variety of minerals. XRT sorters pass high intensity X-rays through particles to generate images of varying greyscale, based on their effective atomic density. The ore sorter then mechanically separates the particles using algorithms based on the images. A popular test currently used to evaluate the amenability of the ore to XRT sorting is to pass the particles through the sorter and obtain the greyscale images showing mineralogical differences. This test provides information on the mineralogical heterogeneity between ore particles for their separation. However, it does not provide an understanding of the actual mineralogical composition of the ore or information pertaining to which other minerals may respond in a similar manner, nor does it provide liberation information. This paper describes a test that combines high resolution X-ray micro Computer Tomography (CT) combined with QEMScan to obtain information about amenability of ore to XRT sorting and to obtain valuable information that can streamline metallurgical testwork programs. This test also provides information relating to particle thickness and associated X-ray attenuation coefficients, desired mineral presence and mineralogical information relating to associated minerals and clays to assist with developing sorting algorithms. Combining the CT and QEMScan can address many limitations of the current method to determine whether XRT sorting technology is appropriate for particular ores. Mineralogy information from QEMScan can identify incidences of; mineral encapsulation, problematic clays, detrimental minerals as well as calibrate the greyscale values of CT data. Additional 3D CT imaging carried out on cores provides spatial information of the minerals within the ore and mineral grades.

Nov 10, 2020

By K Biegaj

During the author’s 25+ year career in mine management in various parts of the world (mostly in Australia), the author has been privileged to live and work in mining towns (not FIFO) for more than 20 years. And has personally observed other people from the mining industry carrying out work at home in an unsafe manner, eg pushing lawn mowers whilst wearing thongs or performing electrical jobs whilst standing on aluminium ladders, as well as many others. It is common that injuries sustained at home whilst on break are not reported upon arrival back on a mine site. A large number of compensation claims for injuries at work, which in fact had been sustained at home, come at substantial extra costs to mining companies.

May 5, 2022

By H Cifuentes, D J. Williams

Despite the recognised importance of tailings management, there remain little data on the potential benefits of biological treatments compared with physical and chemical treatments. The operation of the majority of tailings storage facilities (TSFs) continues to employ mainly physical solutions, such as sub-aerial tailings slurry deposition, with increasing adoption of thickening, paste and filtration to dewater the tailings involving the addition of chemicals such as flocculants and coagulants. However, with tailings production continuing to escalate rapidly due to the increasing demand for commodities and reducing ore grades, available technologies have not demonstrated cost-effective performance at high tailings production rates. This paper examines the emerging role of bacteria to better manage tailings, reducing risks and optimising storage capacity. Bacteria have the potential to enhance tailings dewatering, maintain their permeability, delay the onset of desiccation cracking, and improve their shear strength. Bacteria-treated tailings may be suitable for use as construction materials. Bacteria also have potential in limiting the dusting of tailings and facilitating rehabilitation on closure. The paper describes a series of laboratory involving the addition of harmless bacteria to a range of tailings. The bacteria form a compact material called calcite (a common and stable form of calcium carbonate), which immobilises the tailings particles, releases water, and cements the tailings in a stable and natural matrix. The water released can be recovered or evaporated, depending on site objectives. The bacterial reactions are linked to physical and chemical processes, providing the potential for an optimal mix of technologies for particular tailings and site conditions.CITATION:Cifuentes, H and Williams, D J, 2018. Potential improvement of tailings geotechnical behaviour using bacteria, in Proceedings Mine Waste and Tailings Stewardship Conference 2018, pp 228–238 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 23, 2018

By B Stump

Reliable particle size analysis in minerals processing plants is a critical factor to the economic return of a plant. As recovery of valuable minerals is compromised for particles outside the optimal size range, effective and reliable particle size analysis is more crucial than ever, particularly in the current upswing of the global commodities market. Inefficient particle size analysis can lead to excessive over-grinding, thereby significantly increasing energy consumption and reagent costs, whilst negatively affecting process operation, thickening capacity, water recovery and tailings disposal.Australia’s first installation of a particle size analyser in Iron Ore has been monitored with great interest by the industry. Previously, manual size sampling at Rio Tinto’s Paraburdoo fines processing plant involved off-site sample analysis, with a turnaround measured in days. The Outotec PSI® 500 particle size indicator, commissioned in July 2009, takes approximately three minutes per line at site.The paper will include details on the following:• plant description,• sampling design,• PSI® 500 analyser functionality description, and• key learnings from site.

Jul 11, 2011

By J Bohm, B Csoke, I Tarjan

In process technology, especially in coal preparation, it is often necessary to have a continuous knowledge of the average density of granular material in order to achieve both quality control and process control. The paper presents a new method and means supported by laboratory measurements for the rapid, practically continuous, determination of the average density of continuously supplied granular material through frequent sampling.

Jan 1, 1993

By G S. B Karunatillake

Following a pre-feasibility study, Mount Isa Mines commenced a feasibility study on the deposit of the George Fisher Mine in May 1997. Board approval was granted in May 1998 to construct a 2.5 million tonne per annum mine and to upgrade existing concentrator and smelter facilities. The world-class George Fisher zinc-lead-silver deposit is located approximately 22 kilometres north of the city of Mount Isa, in north-west Queensland and is 2.6 kilometres north of the existing Hilton Mine. It will be a large-scale underground mine, sustaining a profitable zinc-lead-silver business in Mount Isa for at least ten years. This paper will outline the details of the mine that was developed during the feasibility and design phase. It will include a description of the mining methods, ventilation, fill, ore handling, services and infrastructure. The utilisation of existing assets and the development of innovative ideas were essential to the successful economic development of the George Fisher Mine.

Jan 1, 2000

By Jardine G, Woodall C

The Henty Gold Mine, located in Western lasiuania use, uuiusatise solutions to effectively manage a mining operation in an environmentally sensitive setting and has been presented with several environmental awards. Fill is required as part of the mining method to provide passive ground support, minimise rock exposure and ensure maximum recovery of the small but high-grade orebody. The use of the whole portion of leach residue in the backfill reduces the surface tailing disposal requirements. Therefore, High Density Paste Fill (HDPF) has been selected as the most appropriate fill method to meet these objectives. Additional benefits include the minimisation of excess water from fill and the subsequent need for the collection and treatment of water and slimes. There are minimal equipment requirements during placement, thereby optimising mine resources for production. The initial paste fill design was based on the Bad Grund and Ranunelsberg Mines paste fill systems of Preussag in Germany and comprised pumping filtered tailings paste some 1.2 kin uphill from the mill to the mine portal, where cement was to be added before being distributed underground. The system was designed following initial testwork that was undertaken on a bulk sample of ore mined from the scar surface Sill Zone. Subsequently, during the mining of the Zone 96 orehody, it was found that there were significant mineralogical variations in the composition of the ore mined. Following processing, the resultant Icach residue caused significant changes in the paste rheology and therefore the pump and flow characteristics. An alternative solution was implemented that involved the use of agitator trucks to transport the cemented paste to the portal. This required modifications to the fill preparation system and also the underground distribution system. Laboratory strength tests of the HDPF using actual gold plant leach residue showed low early strengths were attained with HDPF containing only filtered leach residue. Therefore, high binder addition rates or an increase in the fill cycle time would be required to allow the fill to gain sufficient strength. A considerable amount of potentially acid generating waste rock also requires underground disposal. By blending the waste rock with the HDPF, the strengths were improved and the required cement addition rate reduced by about one-half. The potentially acid funning waste rock is encapsulated in the highly alkaline cemented paste, minimising the potential for acid generation.

Jan 1, 1998

By R Lachenicht, J Player, A Thompson, E Villaescusa

Kanowna Belle Gold Mine is a deep, high-stress, sublevel open stoping mine located near Kalgoorlie. Seismic activity during the development cycle presented problems, including concerns regarding the exposure of personnel. A number of seismic management systems were developed and tested to monitor seismicity and control the risk. It was recognised that a dynamically capable reinforcement and support system was required to be installed as part of the development cycle to reduce the risk of exposure of the underground workforce to uncontrolled movement of rock. The performance of a new Garford Dynamically capable bolt was measured in tests performed by the Western Australian School of Mines (WASM) at their Kalgoorlie Dynamic Test Facility. Detailed descriptions of the facility and data processing were reported by Player, Villaescusa and Thompson (2004) and Thompson, Villaescusa and Player (2004). The development of the Garford Dynamic bolt is described and dynamic testing results are presented and evaluated. This bolt was implemented in the mining cycle following the testing program; the observed performance is described and assessed in this paper.  

Jan 1, 2008

By M C. Schodlok

Banded iron-formation (BIF) and iron ores were measured using the CSIRO developed TIRHyLogger ™ to assess its ability to map quartz, carbonates and riebeckite. The TIR-HyLogger™ measures continuously spectral refl ectance data from diamond drill core or drill chips with a high spatial and spectral resolution. Samples from twelve BIF, bedded iron deposits (BID) and channel iron deposits (CID) have been analysed. The spectral data were processed with two different approaches. The first approach, focused on the identifi cation of the major minerals, was performed using principal component analysis (PCA). It identified four minerals (quartz, ankerite, riebeckite and goethite) and provided pure spectra called end-members. The second approach included a mineral diagnostic spectral feature extraction involving wavelength position, relative peak heights and relative depths of absorptions. Quartz has a diagnostic absorption at 8.625 µm and ankerite shows a refl ectance peak at 11.275 µm. In addition to the identified end-members, two carbonate populations (calcite and siderite) and two silica species (quartz and amorphous silica) were identified.

Jul 11, 2011

By C Roche, G M. Mudd

The Morobe Province of central Papua New Guinea (PNG) has been mined for gold for nearly a century, although it is only in the past decade that large-scale modern mining commenced. The Hidden Valley gold-silver project began construction in mid-2006 and production by August 2009, and is located in the mountains above Wau in the headwaters of the Watut River. The mine is owned and operated by the Morobe Mining Joint Venture (MMJV), which also owns the Wafi-Golpu project, comprising the Wafi gold deposit and Golpu copper-gold deposit, situated in the Watut River Valley. Together they represent a potential mine of the scale of Ok Tedi or Bougainville or bigger. The MMJV is owned in equal shares by Newcrest Mining from Australia and Harmony Gold from South Africa. Although Hidden Valley was the first large-scale mine in PNG to engineer and build a tailings storage facility, poor environmental management during construction and early operations led to significant erosion of waste rock and sedimentation impacts throughout the ~200 km length of the Watut River. Since then, substantial efforts have been made to improve environmental management, especially waste rock placement and storage and water quality management. While the impacts from the Hidden Valley project appear to be reducing, the saga has heightened concerns by many along the Watut River and across PNG about ongoing impacts from mining.This paper presents the results of an ongoing project in the Morobe Province conducted by the Mineral Policy Institute examining the historical, current and future impacts of mining, including community views, social and environmental impacts and the monitoring and regulation of mining. Overall, there is a clear need to more fully integrate social and environmental issues into life-of-mine planning and go above and beyond regulatory requirements. In this way, some of the lessons learnt – by the community, MMJV and government – can be incorporated before, during and long after mining.CITATION:Mudd, G M and Roche, C, ?2014. Mining in Morobe, Papua New Guinea – impacts, assurance and self-determination, in Proceedings Life-of-Mine 2014 , pp 313–336 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

Future metal prices play a direct role in both the economic evaluation and short to medium planning of a mine scheduling sequence. It is difficult to predict with accuracy the future price of volatile metal commodities, however, it is possible to fix some future metal price, outside of long term contracts by the selling of futures contracts through a commodities exchange. The futures contract represents a fixed amount of a specified quality of a commodity for future delivery at a predetermined price. Several different types of hedging are possible, one in particular which is best suited for mining companies. There are relative advantages and disadvantages when trading in futures contracts and particular reference is made to gold contracts on the Sydney Futures Exchange.

Jan 1, 1980

By H W. Scriba

The development and improvement of computer-based process simulation packages over the past 20 years has provided process engineers with a powerful tool to use in the design of complex metallurgical plants. The use of such modelling tools has enabled the design of process plants that minimise operating and capital costs whilst optimising plant efficiency and recovery. Almost every new project developed in the current market is underpinned by a simulation of the process. In line with engineering best practice this simulation should be based on laboratory/pilot plant test work results and sound assumptions. Any errors that are not identified in the development of the process simulation may have significant effects on the final design and operation of the processing plant. Developing a simulation of the process in a comprehensive, logical and auditable manner is thus essential in ensuring the simulation accurately represents the expected process plant behaviour. A methodology that ensures these requirements are met has been developed by SNC-Lavalin Australia and is described in this paper. The methodology includes the major review stages of data collection, model planning, model building and optimisation, model review, scenario testing and options development, and model reporting. All of these stages should incorporate comprehensive client interaction and review by a suitably qualified representative. In applying these methodologies SNC-Lavalin Australia ensures that the process simulation model developed can be confidently utilised in the design of the process plant, and in the estimation of operating and capital costs, whilst ensuring that engineering best practices are met.

Jan 1, 2008

By C Zhang, I Canbulat, G Fan, D Zhang, C Wang

A clear understanding of the intensity of coal and rock burst is the basis for future research on burst mechanism and control. There has been a wide variety in the description of coal and rock burst damage at different countries using multi-methods, which makes the common understanding even more challenging. Therefore, this paper presents a broad review on the quantifications of intensity of coal and rock burst and seismic risk around the world, considering critical factors including seismic energy, magnitude, peak particle velocity and ejection velocity. It is found that the seismic energy of coal and rock burst can widely range from 0.002 MJ to 60000 MJ, with equivalent Richter magnitude from -1 to 4. The daily seismic energies can be used for seismic risk potential assessment, with energy levels from 0.1 KJ to 10 MJ, which is much lower than the burst sources. The magnitude of the seismic events can be also estimated based on the weight of damaged coal mass and human senses of vibration and sound. For the seismic intensity represented by peak particle velocity (ppv), it keeps constant within fault radius and attenuates with a speed of 1/r4 and 1/r in near and far field respectively, thus it is possible for a small seismic event to induce considerable ppv causing severe damage if the epicentral distance is small enough. There has not been a strong correlation between the ejection velocity and ppv, as seismic energy is only one of the energy sources that contribute to the kinetic energy of burst damage. CITATION:Wang, C, Zhang, C, Canbulat, I, Zhang, D and Fan, G, 2018. Intensity quantification of coal and rock burst risk – a review, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), pp 223–233 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

By H Jones

The paper outlines the adoption and evolution of ‘sustainable development’ as a concept in tailings management practices in the mining industry over the last 30 years. Over 500 lives have been lost in tailings facility accidents since World War 2. The paper outlines commonalities in many of these accidents, particularly the role of excess water. It considers the role effective tailings management can play in enhancing the social acceptability of mining in the future.Tailings management is a major operating cost at many mines while the cost of successfully closing tailings facilities is also very high. Current tailings management practices in the industry are outlined. The technical and engineering challenges of reducing potential risks associated with tailings by reducing water entrainment are described. The successful development of practical techniques to better manage tailings and reduce water consumption and wastage are described. For example, water removal in the alumina industry to produce a paste for dry stacking is now a reality.The future adoption of these new risk reducing techniques by the industry is discussed and the implications of the adoption or non-adoption of these techniques on the industry’s future ‘social licence’ is considered.

Nov 22, 2011

By E M. Wightman, C L. Evans

A recent survey of mineral processors undertaken as part of the International Mineral Processing Council (IMPC) Education Commission identified mineralogy as one of the key skills required for mineral processors (the other key areas being comminution, flotation, physical separation, sampling and extractive metallurgy). Past experience in a number of operations has shown what can be achieved when the data outputs from mineralogical tools are coupled with people with the right skills who can transform the data into actionable information. This paper reviews what has been done successfully in plant operations over a period of more than four decades and gives examples of a range of applications with both long and short-term objectives. The examples demonstrate the usefulness of mineralogical data – both basic and complex – in optimising mineral processing operations, whether the data are applied in a simple analysis or in more complex modelling. Similarly, the examples show the range of options available for operations to access the mineralogy information they need – through in-house experts and equipment based in centralised technology centres, through on-site equipment and experts or through external laboratories and consultants.The examples from industry highlight the huge potential benefit of including mineralogy as an integral part of operational best practice and raise the question of why more operations do not utilise what should be readily available data. Successful application of mineralogical data requires skilled people to generate relevant data of the required quality, together with skilled people to interpret the data (this may be the same person). And, as in any project, corporate recognition of the value of this approach to best practice is required to ensure continuing support. With fewer university courses providing courses in process mineralogy to undergraduate mineral processing engineers and chemical engineers, there is an increasing lack of knowledge about what mineralogical information is needed, how to get the required data and, equally importantly, how to turn the data into useful information.CITATION:Evans, C L and Wightman, E M, 2018. Understanding minerals in mineral processing – the basics and beyond, in Proceedings 14th AusIMM Mill Operators' Conference 2018, pp 363–376 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018

The key to the successful debt funding of a new mining project, whether in economically established or developing nations, is the submission of a comprehensive feasibility study. The feasibility study forms the basis from which the resource banker can construct financial models which govern the amount of available funds, the conditions which control the supply of such funds and the time period over which the loan may be repaid. The bank will wish to ensure that the feasibility study is the best representation and confirmation of reality possible because this model is the basis of the loan security package. Thus the study will be vigorously interrogated by independent experts in all its elements including the ore reserve, mineability, metallurgy, operating and capital cost profile, environmental factors and management. A well constructed feasibility study, undertaken by well recognised and respected independent consultants can save the client company a great deal of real and opportunity costs especially in relation to project timing. Once constructed and operating, the mining project may face one or more completion tests in relation to the loans provided. The genetics of such tests often relate to either the ability of the operating company to become solely responsible for the repayment of the loan or to be rewarded by lower interest rates or some other mechanism. Strong professionalism, accessible records, good checking procedures and high quality, competent site management will greatly assist the client company passing these tests. A record of well established technical competence with its bankers may well assist a company in the establishment of a mezzanine loan for the early development of its next project, thus allowing an earlier return of dividends to shareholders.

Jan 1, 1995

By V A. Chanturia, T N. Matveeva, V V. Getman, A Yu Karkeshkina

The development and application of new effective environmentally friendly reagents for the flotation of thin and ultrathin mineral components is an urgent task. The analysis of the nomenclature of chemicals, including flotation reagents and flocculants, showed that water-soluble polymers (WSP) might be used in flotation separation of fine grinding products containing non-ferrous and precious metals. Water-soluble polymers that are responsive to temperature changes are the most attractive as reagents during flotation. These are the thermo-responsive polymers or thermomorphic polymers. The presence of nitrogen and oxygen atoms in the polymer molecule contributes to the formation of a coordination bond with non-ferrous and precious metals. A research conducted at the ICEMR RAS within the framework of the scientific school of Academician of the Russian Academy of Sciences Chanturia helped to develop a method of flotation of finely ground mineral particles containing valuable components using modified thermomorphic polymers. The paper focuses on the experimental study of poly (vinyl caprolactam) (PVC) as a flotation reagent for gold recovery from finely ground mineral products. PVC is a ready-made water-soluble thermosensitive polymer that does not require complex synthesis. PVC has a high ability to form complexes in an aqueous environment when heated. According to experimental data, the polymer interacts with gold nanoparticles, contributing to the extraction of gold from fine mineral products and the tailings that makes it perspective as an additional flotation agent for the processing of gold-containing ores.

Aug 24, 2022