Search Documents

By P Walker, I Crnkovic, D Bennett

The Phu Kham deposit represents a copper-gold porphyry system, with mineralisation present in skarn, stockwork and disseminated styles. Significant folding and alteration events have created a complex heterogeneous mineralogy horizon. Weathering and water table contact have created a leached zone, overlying transition zones with supergene chalcocite- dominant secondary copper mineralisation and clay-rich gangue. Primary ore copper mineralisation is mainly chalcopyrite with minor bornite. The major challenges to the copper-gold flotation process are a wide size distribution of chalcopyrite mineralisation and poor primary grind liberation, a high pyrite content in skarn ore requiring aggressive pyrite depression conditions, clay-rich gangue and non-sulfide copper mineralisation in weathered zones, and a significant association of gold with pyrite.The Phu Kham concentrator has been developed as a conventional semi-autogenous grinding (SAG) and ball milling circuit followed by selective rougher flotation, regrinding and cleaner flotation to produce a copper concentrate containing payable gold and silver values. The concentrator flow sheet design offered a capital efficient compromise between high copper recovery bulk sulfide flotation with large cleaning capacity, and lower recovery copper selective rougher flotation to ensure concentrate specification of 24 per cent copper grade could be achieved. This paper will examine and discuss concentrator flow sheet development, including projects implemented since commissioning to improve copper recovery, and future projects designed to maintain and enhance copper in concentrate production with decreasing copper grade and increasing pyrite content of ore feed, and increasing hardness of primary ore.CITATION:Bennett, D, Crnkovic, I and Walker, P, 2012. Recent process developments at the Phu Kham Copper-Gold Concentrator, Laos, in Proceedings 11th AusIMM Mill OperatorsÆ Conference, pp 257-272 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 29, 2012

By L Mikhael Gurieff, D Baas

The Phu Kham Copper-Gold Operation (Phu Kham Operation) is located in the Lao People's Democratic Republic and is owned and operated by the Lao-registered company, Phu Bia Mining Limited (PBM). Australian-headquartered copper and gold producer, PanAust Limited holds a 90 per cent interest in PBM; the Government of Laos owns the remaining 10 per cent. The Phu Kham Operation was commissioned in 2008 with an initial concentrator nameplate throughput of 12 million tonnes per annum (Mt/a). Subsequent improvement projects, including the Phu Kham Upgrade Project (PKU), completed in 2012, and the Phu Kham Increased Recovery Project (IRP), completed in 2013, increased the design throughput to 18 Mt/yr. In 2016, the actual mill throughput exceeded 19 Mt/a, this throughput is budgeted to be maintained until the end of 2020.The concentrator flotation circuit upgrade, completed during the IRP, called for a non-selective bulk sulphide concentrate to be generated from the rougher circuit. This in turn caused the mechanical flotation cells in the cleaner circuit, particularly those in the second cleaner bank, to become volumetrically overload. The overload reduced the cleaner circuit performance to approximately 92 per cent copper recovery at a 23 per cent copper concentrate grade, below the expected 95 per cent recovery. This bottleneck restricted copper units entering the plant to approximately 14.5 tonnes per hour (t/h) due to uncontrolled recirculating load build-up in the mechanical cleaning circuit.Maintaining the operating methodologies would have led to a copper production shortfall beyond 2016, to address this shortfall the Phu Kham Operation looked to optimise the Jameson Cell and mechanical cleaner circuit performance. The work included fundamental application of flotation practice and modelling, mineralogical analysis, bubble size analysis, plant surveys and test work. The results were used to develop and implement an innovative automated control system strategy incorporating flotation theory and operating strategies. The automation has the ability to quickly adapt to disturbances in the circuit and maintain optimised performance with little or no intervention by flotation operators.Upon completion, cleaner recovery increased to 95 per cent at a final concentrate grade of 23 per cent copper, and copper units entering the plant increased to 17.5 t/h.CITATION:Baas, D and Mikhael Gurieff, L, 2018. Developing flotation circuit control and automation for the Phu Kham Copper-Gold Operation concentrator, in Proceedings 14th AusIMM Mill Operators' Conference 2018, pp 37–58 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018

By Y Lanwin

The Australian mining industry, a cornerstone of the nation’s economy, is on a journey towards greater equity and inclusion. Th paper introduces a comprehensive exploration of how universal design principles, stemming from architectural roots, have evolved through automation and digital technology into the more encompassing frameworks of inclusive design and equitable design. The paper proposes a practical framework for those involved in work, facilities and equipment design in the mining industry to identify and assess for equity and inclusion. Universal Design emerged in the 1960s with a primary focus on architecture, aiming to create spaces accessible to people of all abilities. Its foundational principles sought to ensure equitable use, flexibility, simplicity, perceptibility, tolerance for error, low physical effort and optimal spatial considerations. Over time, these principles evolved and expanded beyond physical spaces, finding applications in various fields, including technology, education and transportation. In response to advancements in technology and a growing understanding of the multifaceted nature of diversity, Universal Design evolved into Inclusive Design. Inclusive Design goes further than mere accessibility, considering a broader spectrum of users with varying cognitive, sensory, cultural and socio-economic backgrounds. It emphasises user centred design, customisation options, diverse user research and continuous iteration. Equitable Design emerged as a framework that addresses not only the diversity of needs but also systemic disparities. It emphasises fairness, justice and the elimination of structural inequities. Equitable Design encompasses accessibility and affordability, representation and diversity, ethical considerations and community engagement. This paper will explore the applications of these design principles through a series of case studies including village and on-site facilities, remote operations and office based work design and technology design. By applying these frameworks in a mining context, the paper proposes that mining companies and suppliers can improve diversity, equity and inclusion leading to safer, more engaged and productive workplaces.

Apr 16, 2024

By A Bird

Gravity gold circuits have an important part in reducing operating costs and maximising recovery in modern gold plants where coarse gold is present in the ore body. The design and selection of equipment has a vital part in the overall effectiveness of the gravity gold circuit. There are a number of associated factors that need to be taken into consideration when selecting the most suitable equipment for gravity gold circuits including occupational health and safety, security and labour requirements. This paper is a case study that outlines the validation behind the design, selection of equipment and subsequent benefits of the recent upgrade of the gravity circuit at the Marvel Loch gold mine with the main component to the upgrade being the installation of a Consep Acacia Reactor. Since the upgrade there has been a significant increase in gravity recovery, which has reduced the amount of gold reporting to the leaching circuit therefore reducing reagent consumption and overall operating costs. There has been an increase in overall gold recovery and therefore increased gold production. The benefits to occupational health and safety include the removal of toxic gases being released in the gold room during the previous practice of gold concentrate calcination and the removal of the arsenic and nickel from the gold doré, which poses a risk during refining. Manual handling and security has improved as there is no physical contact with gold concentrates during the automated process using the Acacia reactor. The total time for gold room personnel working in the gold room has also reduced from around six hours per day to less than one hour per day.With the continuing development of low grade gold deposits, there will be an increase in demand for low capital, high recovery gravity gold circuits that can significantly increase overall production while reducing operating costs.

Aug 8, 2011

By A Giblett, B Putland

This paper provides a simple guiding framework for grinding circuit optimisation, focussing on common themes in past optimisation success stories, the conditions for success and techniques that can be employed to identify and define opportunities. Many significant grinding circuit improvements have been reported for operating plants, based on recurring themes such as the optimisation of mill feed size, mill liner design, process control, critical size, grinding media and classification. The paper condenses these experiences into a set of simple questions for the operator to ask, and provides guidance towards identifying and achieving the optimisation goals.CITATION:Giblett, A and Putland, B, 2018. The basics of grinding circuit optimisation, in Proceedings 14th AusIMM Mill Operators' Conference 2018, pp 129–140 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018

By E McLean

The decision making check-list and hierarchy of information for process and plant design is generally wide-ranging and complex. The nature of grades, mineralisation and ore types in an ore body, its mine development sequence, and the body of results from metallurgical and physical test work present complex and competing influences on flowsheet development, values for design, equipment selection, plant efficiencies and operating strategy. The challenge is how to manage all these variables, to understand their impacts on performance, and how best to provide a cost-effective plant design and robust process that meets daily/weekly/monthly operating objectives. Throughput, production and grade or product specifications need to be met. The ore body is not average; its range of metallurgical and physical characteristics may be moderately to highly variable. This paper assesses some of the key competing influences and conflicting issues in design and equipment selection, and their effect on production and performance expectations.

Aug 8, 2011

By G J. Halstead, R C. Steinhaus

The True Pipe® in-line sampler was developed in an attempt to address the need for a mechanically reliable and correctly designed sampler to suit one-dimensional pressurised slurry pipelines, often found in metallurgical process plants but for which no reliable and representative sampling solution as yet exists.The design, whose operation is based on the principle of symmetry, is described by Dominique François-Bongarçon (2005) with the synchronous opening and closing of relevant valves. It representatively isolates portions of the particulate material stream at predetermined intervals for effective extraction of primary increments for subsequent sample compositing.Theory of Sampling applicable solutions have proven elusive in flowing pressurised particulate material streams, with various attempts to date not having formulated a viable, mechanically reliable and acceptable design.Compliance to sampling theory is critical, and a number of tests were conducted where certain operating parameters were altered to determine their influence and sensitivity on sampling representativeness.The results of the initial series of tests performed on a carefully designed rig are presented, with additional work discussed for necessary investigation in the near future.Getting closer to a robust, economic and correct design for this challenging application in the minerals industry may now not be that far away. Plant management staff will see improved metallurgical mineral balances around their process plants and significantly reduced sampling discrepancies, particularly in tailings applications. Improved quality control is now possible where, due to plant head room constraints, classical cross stream sampling methods cannot be employed.CITATION:Steinhaus, R C and Halstead, G J, 2014. True pipe sampler – a correct design utilising the principle of symmetry in pressurised slurry particulate streams, in Proceedings Sampling 2014 , pp 127–134 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 29, 2014

By S Robinson, A Turner, R Dale, C Butler

"Sandfire Resources NL- (‘Sandfire’) DeGrussa definitive feasibility study (DFS) identified geometallurgy as a major factor in achieving optimum plant performance at the DeGrussa mine. A geometallurgical initiative was created to proactively investigate this issue, and a key initial achievement was the 2013 paper by Condon et al (2013) on developing a working geometallurgical model from first principles. Significant advancements in Sandfire’s geometallurgical understanding since that publication now shape how information is presented and communicated.The main geometallurgical parameters so far identified as critical factors affecting plant performance are Cu:S ratio, iron sulfide mineralogy, talc carbonate content and sphalerite content. Apart from specific mill strategies, geometallurgical issues have been managed through communication between departments and strategic run-of-mine (ROM) pad management.This paper uses the current theories of geological evolution of the volcanogenic massive sulfide (VMS) deposit at DeGrussa, to discuss the variability between the orebodies C1, DeGrussa (sea floor mounds) and C4, C5 (sub-sea floor replacement) to highlight the different issues each orebody is expected to encounter when processing.A zone of altered low-grade mineralisation surrounds the main orebodies at DeGrussa, referred to as a halo. Talc minerals are often patchy within this halo and often cause significant recovery issues during processing. This halo has been successfully modelled using MgO as a proxy. The ability to model the talc material assists with both identifying potentially problematic zones for processing and geological interpretation of the ore deposits evolution.Early in geometallurgy studies at DeGrussa it became apparent that it would be useful to identify processing performance prior to mining. This necessitated the incorporation of specific sulfide species into the mining block model. These attributes are interpolated from the logged sulfide estimates allowing a clear picture of the abundance of each mineral type within a defined area.In conjunction with the block model a geometallurgical factor (GMF) graph was developed, identifying sulfide mineralogy based upon mineral assays. These two recent additions to the model provide a clear picture of the nature of the ore sources that will be presented to the processing plant.The future of geometallurgy at DeGrussa will see these tools used to aid mine scheduling with a view to further improve processing recoveries.CITATION:Butler, C, Dale, R, Robinson, S and Turner, A, 2016. Geometallurgy – Bridging the Gap between Mine and Mill: a Case Study of the DeGrussa Geometallurgy Program, in Proceedings The Third AusIMM International Geometallurgy Conference (GeoMet) 2016, pp 77–88 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jun 15, 2016

By G F. Johansen

The erratic and localised occurrence of economic gold grades is a common feature of high-nugget effect gold veins. The nugget effect is a consequence of small-scale geologically controlled enrichment, and the inclusion or exclusion of sparse gold particles because of the sampling process. Such deposits do not always contain visible or coarse gold, and can be characterised by fine gold particles. Economic grade accumulations are generally contained within discrete oreshoots, which are surrounded by barren to low-grade material. Problems are often encountered where small sample types (eg drill core or channel samples) often vastly understate in situ grade, due to their general inability to intersect rare gold particles. As a result, the definition of grade and its distribution is often challenging, and leads to substantial resource uncertainty. Proxies, or indicators for grade, can help the geologist gain a better understanding of grade distribution and grade potential. These are based upon geological (eg mineralogical, textural, etc) and/or geochemical (eg specific elemental ratios, fluid inclusion compositions, elemental correlations, etc) criteria. The paper discusses the use and application of such proxies through three case studies.

Jan 1, 2004

By I Ametov, S Harmer, R Alford

A process that allows selective flotation separation of low Cu/S ratio minerals (chalcopyrite and pyrite) from high Cu/S ratio minerals (bornite and chalcocite) from a mixed copper mineral concentrate under controlled oxidative-reductive potential conditions has been developed. The process has been extensively tested on samples with varying mineralogy using laboratory batch flotation tests and mini pilot plant trials.In this process, the mixed final copper mineral concentrate is purged with nitrogen, and then treated with sodium dithionite to achieve a slurry Eh in the -200 to -100 mV standard hydrogen electrode (SHE) range. Flotation was then carried out using nitrogen gas. As a result, a low Cu/S ratio concentrate (<1.3) and a high Cu/S ratio (>1.6) tailing stream were produced. QEMSCAN analysis of the flotation products showed that more than 85 per cent of the chalcopyrite and 95 per cent of the pyrite reported to the froth concentrate. Chalcocite and bornite were almost evenly distributed between the concentrate and tailing streams.Surface analysis studies, focused on the mechanism of separation, showed that at a negative redox potential xanthate and possibly dixanthogen are the dominant hydrophobic species on the surface of chalcopyrite and pyrite. As a result, the flotation of these minerals remained unaffected. In contrast, a much lower concentration of xanthate species on the surface of chalcocite and bornite particles was observed. Therefore, it is likely that at low Eh the copper xanthate complex desorbs from the chalcocite and bornite surfaces, causing a decrease in surface hydrophobicity and the diminished floatability of chalcocite and bornite.CITATION:Ametov, I, Harmer, S, Grano, S and Alford, R, 2014. Selective flotation of chalcopyrite and pyrite from a mixed copper mineral concentrate under controlled redox potential conditions, in Proceedings 12th AusIMM Mill Operators’ Conference 2014 , pp 131–140 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 1, 2014

A recoverable uranium resource, shown to be suitable for in situ leaching, was discovered at Honeymoon in South Australia in 1971. Exploration of the deposit was carried out during the period from 1973 to 1979. Uranium mineralisation occurs in a coarse-grained unconsolidated sand aquifer located in the Yarramba Palaeochannel at a depth of approximately 110 m. Following initial development during 1979 to 1983 and the construction of demonstration leach facilities, the Project was put on hold. Southern Cross Resources purchased the Project in 1997. Government approval was received in March 1998 for the operation of on-site demonstration leach and recovery facilities while an Environmental Impact Statement was prepared and a 1000 tpa commercial production plant was designed. The Environmental Impact Statement (EIS) was released in June 2000 and operation of the test facility was completed in August 2000. Acceptance of the EIS by Commonwealth and South Australian state governments was announced on 20 November 2001. A Mining Lease was granted over the area of the proposed ISL operation on 8 February 2002. Operation of the Project is entirely dependent on using highly saline underground water resources to supply process and human needs. The management of discharge streams from the plant by re-injection was approved. The Honeymoon demonstration plant was the first adaptation of the solvent extraction process to highly saline in situ leach solutions. As such, it incorporated a number of unique operating and installation features. The trial period enabled optimisation of the process chemistry, additives and management and serves as an invaluable base for the proposed plant design and future operation. This paper discusses the nature of the uranium occurrence, the effect of saline water on the leach process and equipment, project design and environmental considerations, the requirements for disposal of discharge streams to minimise the impact on the arid environment and the requirements for rehabilitation following project completion.

Jan 1, 2002

We outline a first version of an ambitious goal: The world's first horizontal (matrix-independent) generic sampling standard. The specific needs and requirements are overwhelming, as all the world's analytical standards follow strict matrix or material type classification pigeonholes, leading to a plethora of analytical standards. One could rightly expect a similar multiplication regarding sampling standards, yet the singular HORIZONTAL is aimed at being truly generic. Also the existing style of standards writing is cumbersome and partly contradictory. The current work is presently being pursued in CEN and European Union standardisation regimens, for which reason full disclosure and publication is not allowed. Respecting this constraint, we unofficially present selected key issues involved in developing HORIZONTAL: The objective and scope of a horizontal sampling standard is to delineate the minimum set of principles and procedures needed to guarantee documented representative sampling for all types of materials. The horizontal standard is designed for two types of use: 1. auditing/assessing/ improving the reliability of an existing sampling procedure, and 2. design and implementation of a new sampling procedure (new lot type). The principles in this standard are all derived from the Theory of Sampling (TOS), but the standard is far from a mere collection of TOS principles. Representativeness is a characteristic of the sampling process, not of samples themselves. For practical purposes, the horizontal standard follows the fundamental distinction between 'stationary lots' (0-D, 2-D, 3-D lots) and 'dynamic lots' (within TOS aka process sampling - including extended, non-moving 1-D lots). TOS' principles of 'correctness' must never be broken at any stage, lest representativeness is irretrievably lost. The horizontal standard is not written in the mandatory fashion for legally binding matrix-specific standards, eg ISO - for the present overarching purpose a different style had to be developed. The standard must be immediately understandable in full, which merits special demands, eg extensive use of didactic illustrations. HORIZONTAL introduces an all-inclusive sampling variability measure, Relative Sampling Variance (RSV) which is for sampling of stationary lots as variographics is for process sampling - RSV is to be used as a quality criterion for any stationary sampling procedure as applied to a specific heterogeneity (lot/material). The target for this standard is all individuals, companies, organisations and regulatory bodies who are responsible for sampling: technicians, process engineers, laboratory personal, academic and industrial scientists as well as project leaders, technical managers/directors and top managers. Based on current R&D we illustrate the principles promulgated by HORIZONTAL with cases from exploration and mining of minerals commodities, a Finnsh 'Autosampler' at work in the mining context (RSV) as well as sampling equipment for use in the cement and mineral commodities industries. This is an ABSTRACT ONLY. No paper was prepared for this presentation.

Mar 1, 2010

By R L. Grogan

Mining is currently undergoing a progressive expansion into novel environments (such as the deep ocean), commodities (such as tantalum, rare earths, and other ‘green economy minerals’), and new methods (such as the autonomous underwater cutting machines required to operate in the deep ocean environment, or the use of expanding grouts to deliver a blast-free mining method). The advent of novel mining, environments and commodities heralds an era that will undoubtedly start with much discomfort on the part of regulators and stakeholders, due to a feeling of overwhelming uncertainty. These proposed mining scenarios have few precedents, few examples of successful implementation, short baseline monitoring periods, and few examples of legacy sites that may assist with understanding long term risk and exposure. The evolution of the environmental and social impact assessment (ESIA) process in many regulatory environments recognises stakeholder engagement in a formal and facilitated manner. This is a positive step, and allows stakeholders to be much more meaningfully involved in the permitting process than they historically were. However, with this advance comes the challenge of identifying and communicating with stakeholders; sharing information in a meaningful way, fostering relationships with what can be an extremely large group, and delivering on commitments that inspire confidence to permit operations that have never been permitted before. In order to meet this challenge, it is suggested that changes to collection of data, communication of data, the nature of commitments, and the reporting of performance need to be made in order to effectively communicate management of new technologies, and the impacts that mining may have in new environments (such as the deep ocean). The communication challenge is necessarily greater when describing technology that has never been used, or environments that have never previously been accessed by humans on an industrial scale. CITATION:Grogan, R L, 2018. Permitting in the face of uncertainty – how to deliver confidence to regulators and investors, in Proceedings Life-of-Mine 2018, pp 46–48 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 25, 2018

By M Sykes

Gold was initially discovered at Ballarat in 1851. After initial alluvial mining, underground quartz mining commenced in 1853, continuing until 1918. The historic miners were considered to be capable of mining anywhere in the world after overcoming the difficult conditions within the Ballarat goldfields. Whilst mining has changed dramatically since the early 1900s the challenges with underground mining at Ballarat have not. Modern pumping systems cope with the moderate water inflows. However, modern machinery and efficient mining methods influence opening sizes and extraction techniques. In some cases modern techniques have accentuated the challenging ground conditions and complex orebodies that were faced by the historic miners. As the Ballarat East project has progressed towards production, technical challenges relating to geomechanics and mine planning are being resolved resourcefully.

Jan 1, 2008

By D Kent

"There has been a revolution occurring in underground mining over the last several years, where big headline items such as the Internet of Things (IoT), optimisation, managing data, data mining etc – the list of current catchphrases, goes on. In the end these are nothing new; but the ‘things’ (sensors) are becoming smaller, cheaper and easier to deploy, and the analysis much more powerful as computer processing speeds increase. However, to take advantage of the myriad of devices out there and gain the processing power to analyse and use the data, a reliable ‘conduit’ is needed for that information to be delivered where it can actually be used. That is, a high quality data network.Modern mining is like any other industry in the information age: the access to reliable data is the first, critical step in improving productivity (Stevens, 2015). The convergence of communications onto an IP (Internet Protocol) backbone has been the driving force in enabling the productivity gains in general industry over the last two decades.This paper overviews how this technology has developed as an enabler in accessing productivity and safety benefits, and how it has used access to large amounts of data to manage mining processes underground. Reams of data are useless, but with the reliable receipt, analysis, processing and feedback system in place to use that data, benefits can be realised.Automated mining systems are increasingly being seen as a key requirement for a productive mining operation, and the importance of an integrated communication network infrastructure to support such systems is growing. Another emerging driver is the much talked about IoT and data analytics, both dependant on reliable, accurate, high volume data.The author will outline how communication infrastructure is fundamental to the operation of such systems, and explain why the resultant communication networks require much more than just increased bandwidth (data capacity) to properly support the automation and other data hungry systems within the overall mine operation.Mining operations embarking down this road are discovering that the required network must be based on a true enterprise level architecture to, not only enable the mine’s current plans for remote or automated mining, but also to provide a scalable and integrated platform for future developments. The emerging issues for the communication network to truly support automation systems include: increased complexities of operating and maintaining multiple networks integration issues with disparate systems problems with reporting, particularly as demands for corporate reporting and compatibility with enterprise systems become the norm ongoing management challenges, which will only increase with the proliferation of new technologies.How certain mining operations lay the necessary foundations to meet their current requirements, while supporting their visions for a more automated and proactively managed mine, will be explored.CITATION:Kent, D, 2017. Modern mining – why bandwidth matters, in Proceedings 13th AusIMM Underground Operators’ Conference 2017, pp 123–128 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 16, 2017

By C Delwig

ThyssenKrupp specialises in the manufacture of high-grade steel-sheet products. Its main customers include the automotive, construction, household appliance, energy and packaging industries.At its works in Duisburg, Germany, ThyssenKrupp Steel Europe produces 12 Mt of crude steel annually, making Duisburg one of the world’s largest steel hubs.ThyssenKrupp have installed an online elemental analyser and limestone dosing control System on one of three Sinter strands at Duisburg in an attempt to control the sinter raw mix with better precision. Traditionally, set point changes to the raw mixture were made after sampling and laboratory analysis of the sinter product. The analyser chosen uses prompt gamma neutron activation analysis to determine the elemental content of moving material on a conveyor each minute and was supplied by Thermo Fisher Scientific. The project goal was to control the CaO/SiO2 ratio (basicity) and reduce its variability in the sinter feed.Evaluation of the system has shown that the addition of the online analyser reduces the time lag related to the former method, therefore upset conditions can be reacted more quickly by the control system, and this has resulted in a more stable sintering process. As a result, the sinter feed variability in case of the basicity has been reduced by half. While CaO/SiO2 control was the initial aim of the project, a number of other benefi ts have been realised, such as a reduction in return fi nes and a financial benefi t of 0.11 €/ton of sinter attributed to the reduction of coke breeze and limestone. ThyssenKrupp Steel Europe has identifi ed that additional information available from the analyser could be used to optimise the complete sinter process.The project was carried out with a financial grant of the research program of the ‘Research Fund for Coal and Steel’.

Jul 11, 2011

By A L. Randriamanjatosoa, G Small, C Greet

In flotation simulation models, the effects of pulp chemistry other than pH are often ignored and reduced to particles hydrophobicity or contact angle, neither of which can be measured readily in real time in an operating plant. The flotation response of a given sulphide mineral is known to be influenced and can be improved by changing the chemical characteristics of the pulp during grinding and flotation. The on-line measurement of pulp pH, potential, dissolved oxygen, temperature and oxygen demand of a process stream was completed with the PCM® (Pulp Chemistry Monitor) developed by Magotteaux in this study. The data generated together with relevant plant operating parameters were used to construct an empirical model and simulate the metallurgical performance of the ore. The same approach was also applied to laboratory flotation tests data using various grinding media types. The flotation models better fit the actual data when the chemistry of the pulp is taken into account.CITATION:Randriamanjatosoa, A L, Greet, C and Small, G, 2018. Effects of pulp chemistry on plant and laboratory flotation modelling, in Proceedings 14th AusIMM Mill Operators' Conference 2018, pp 423–432 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018

By C DahnTr-Lindqvist

The Kiruna mine produced about 19 Mt processed iron ore in 1999 using sublevel caving. General failure in the hangingwall has been widely studied and its mechanism is rather well understood. Failure in the footwall is more recent and not perfectly explained. Plane shear failure and Hoek and BrayÆs circular failure charts were successfully used to match the first surveyed failure surfaces. The footwall is not free yet but covered by a caved waste rock abutment whose exact behaviour is poorly known. Based on new field data and numerical models (FLAC), the following paper presents recent improvements in understanding the Kiruna mineÆs footwall failure process.

Jan 1, 2000

By L Nicholls, A Parbhakar-Fox

Reprocessing Queensland’s historical copper tailings for critical minerals is an opportunity to circularise the state’s mining industry by converting waste liabilities into assets. Mine waste valorisation enables economic rehabilitation of legacy mining sites, improves environmental outcomes, and can establish a secondary resources sector that produces a sustainable supply of critical minerals to supplement growing global demands (Australian Government, 2023). The North-West Queensland Minerals Province (NWQMP) hosts numerous copper mines with known cobalt mineralisation (Degeling, 2020). Cobalt is a critical metal essential for green energy and battery technologies, however its global supply is at risk due to geopolitical and ethical concerns (Rachidi et al, 2021). Historically mining in the NWQMP has focused on copper, leaving cobalt to theoretically accumulate in the mine waste. First-pass geometallurgical characterisation of waste repositories by the Sustainable Minerals Institute identified Capricorn Copper as a key site for further investigation into cobalt deportment and recovery potential.

Aug 2, 2023

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