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The metals titanium and zirconium and their alloys occupy individually unique positions in the catalogue of metallic materials available for engineering applications. Because of the uniqueness of their usage in the aerospace industry, in the case of titanium, and in the nuclear industry, in the case of zirconium, the except- ional resistance of both the metals to the majority of corrosive media is often overlooked. The cost factor in the application of these more exotic metals has, in the past, been a major considerat- ion in the rejection of titanium and zirconium as constructional materials in areas of usage where their superior corrosion resistance strongly favoured them over more conventional metals and alloys. The cost differential, vis-a-vis austenitic stainless steels, for example, is not a trifling matter, being of the order of 6 : 1, when compared on a weight basis. However, if one considers the cost, for, say, sheet product on an area basis, the ratio is redgced to approximately 3.4:1. If one also takes into account the enhanced performance of the more expensive material and the sub- sequent increase in service life and decrease in plant down-time, the economics of the usage of materials such as titanium becomes much more attractive and, indeed, highly competitive,

Jan 1, 1969

By J Q. Shi, M Karakus, Y Liu

Predicting the spatial distribution of rock mass properties in cave mining is a critical challenge. In this study, we introduce a novel machine learning-based model to advance our comprehension of rock behaviour. This model specifically focuses on the spatial distribution of rock mass and mechanical properties, a crucial aspect of our understanding of rock mechanics. Our model is inspired by the recognition that neighbouring information serves as crucial prior knowledge for predicting the spatial distribution of these properties, wherein closer neighbours are likely to exhibit similar characteristics. To effectively capture and model these neighbour relationships, we design a neural network-based model to map the spatial locations within the data set into a new highdimensional space. Within this transformed space, we utilise Euclidean distance to identify N neighbours. Leveraging these neighbours, we introduce a straightforward yet highly effective approach—label propagation—to construct a graph that illustrates neighbour relationships. This graph not only facilitates the prediction of the spatial distribution of rock mass properties but also offers a measure of uncertainty for these predictions. We validate the proposed method using a real rock data set and showcase its efficacy in capturing intricate relationships and distributions within rock properties, enabling precise predictions across diverse spatial scales. Our results underscore the potential of machine learning-based approaches to revolutionise the field of rock mechanics, providing valuable insights applicable to geotechnical engineering, mining, and other sectors where an accurate understanding of rock properties is paramount. This model has direct practical implications, offering a new tool for geotechnical engineers and mining professionals to enhance their understanding and prediction of rock properties, thereby improving safety and efficiency in their operations.

Sep 1, 2024

By A N. Terblanche, D S. Smit

The paper discusses the improvements achieved after an external sparger flotation column, 1.42 m diameter by 9.5 m high, was installed as a re-recleaner unit at the Northam Platinum LtdÆs UG 2 plant in South Africa. The paper also evaluates the pilot plant data prior to the industrial size column installation as well as the accuracy of scale up from pilot to full-scale operation. Since the installation of the PrepQuip flotation column, the final concentrate upgrade ratio improved from 83 to 105, the 3PGM+Auå recovery improved from 79.7 per cent to 81 per cent and the Cr2O3 content in the final concentrate decreased from five per cent to 2.8 per cent. The upgrade ratio can be improved to 125 with an overall 3PGM+Au recovery of 80 per cent. Conventional mechanically agitated flotation cells achieved only 74 per cent recovery at an upgrade ratio of 125.

Jan 1, 2005

By A M. Ebbels, D Pratt

The current commodities super-cycle has seen an explosion in the number of mining projects demanding human resources throughout the world. The demand for key personnel currently far outweighs the international talent pool and will take several years to subside. A highly effective project team can be the difference between a successful project and a bad public relations exercise. Building an effective team and retaining the team members has become one of the major influencing factors for successful project development in the mining industry in the last decade.Increasingly, international teams are being established combining skill sets, subject matter experts, unique previous experiences and diverse cultures to deliver mining projects all around the world.This paper explores the characteristics of a highly effective team, the communication and geographic challenges and some potential pitfalls which influence the ability to form effective teams within the mining industry.CITATION:Ebbels, A M and Pratt, D, 2012. A great project team - Bringing together location and culture, in Proceedings Project Evaluation 2012 , pp 197-202 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 24, 2012

By M Stewart, J Petrie, L Basson

This paper explores tools which have the potential to promote and assess the formation of partnerships between the minerals and energy industries to enhance the economic, environmentally responsible and socially acceptable use of energy. There is a need to look at energy provision and energy services in an integrated manner with key drivers for economic development û both locally and regionally. The minerals sector will remain highly significant to regional economic development in a number of globally significant regions in the medium term. Furthermore, mining, minerals and metalsÆ projects are both consumers and, in some cases (potential), generators of large amounts of energy (electricity included). It is therefore appropriate to focus on the promotion of partnerships between energy providers and the minerals sector which seek to improve resource efficiency within the combined minerals/energy envelope, guided by the tenets of Sustainability.Whilst there has been considerable development of systems analysis tools in recent years to address this sort of æcomplex systemsÆ analysis (Life Cycle Management, Cleaner Production and Industrial Ecology arguments for example), there is no effective roadmap available to decision makers to guide the selection and exploitation of these tools in different contexts. Our previous work developed a Decision Support Framework (DSF) which provides some guidance here, but only within the context of coal-based power generation. The DSF employs the tools of Multi Criteria Decision Analysis (MCDA), within which trade-offs between competing objectives are explored in such a way that alternatives can be compared without necessarily reducing all the different cost and benefits to a common basis (eg a monetary basis). Even if the existing DSF is extended to include all aspects of supply-side management, it is still lacking the necessary tools to analyse energy providers as dynamic network partners within minerals projects (or indeed any resource or manufacturing sector). New models are required for this, which firstly, seek to characterise such network structures, and secondly, enable the application of the necessary analytic tools to exploit these partnerships and networks for optimal performance.This paper explores the development of such an integrated set of network analysis tools, and their relation to the DSF. Due consideration is given to the choice of the attributes needed to characterise partnership linkages and network integrity (eg security of supply of electricity), and the efficiency of material transformations within any node of the network (as a function of energy consumption), and the impact that this has on the viability of other linkages (eg due to reduced availability of raw materials). We discuss how these perspectives help shape the form of objectives to be considered by MCDA.

Jan 1, 2004

By A Castillo, K Wiese, L Panduro Robles

For decades, organisations worldwide have been working to overcome challenges associated with new technology adoption while keeping up with rapid growth, development, and globalisation. In minerals processing, the challenges in developing and implementing solutions that contribute to the mining value chain are unique from other markets, as mining operations expect that world-class suppliers provide them solutions to gain a competitive advantage in their operation, production, performance as a financial asset, and as a long-term partner as we move into the future of mining. A simple shift in mindset is proven key to successful technology implementation. Change leaders must no longer think of their expertise in the area of application as their only responsibility; they must make a mental shift and see themselves in dual roles that strive to integrate the perspectives and needs of both developers and users. Successful change leaders must: (1) collaborate, seeking user involvement to ensure fit between product and operational needs, (2) demonstrate commitment to receive new technology, and (3) communicate to achieve an eventual shift of ownership from supplier to users that is seamless. Additionally, this strategy contributes to the mining value chain, as it allows developers and implementers to evaluate how change contributes to the asset’s position both within the company and in the commodities market. This paper will explain the shift in perspective for new technology implementation in detail and provide recommendations that operations can emulate, using examples of real challenges and lessons learned during a commissioning of the CYCLONEtrac™ Particle Size Tracking (PST) system at Cerro Verde’s C2 Concentrator. This concentrator has led technological change for plant optimisation, witnessed improved Net Metal Production (NMP), among other benefits with PST, the only technology in the market capable of providing real-time, online, and direct particle size measurement at the individual hydrocyclone level

Aug 24, 2022

By J Pan, G Qiu

In this paper, an analysis is made of the present situation in the Chinese steel industry and its demand for iron ores. It is shown that the demand for iron ores has been growing substantially with the rapid development of the steel industry all over the world, especially in China. However, the iron ore market is currently in the situation where supply exceeds demand due to the economic crisis, with more investment in mines and less output of steel for several years ahead all over the world. Gigantic pressure is confronting the Chinese steel mills due to the too high and irrational price of iron ores. It is time to return the price of iron ores to a normal position much closer to their value. More attention has therefore been paid to developing low-grade and complex iron ore resources in China due to the irrational price of imported iron ores. More innovative mineral processing processes have been developed to tackle these complex resources. A systematic introduction to the development of beneficiation processes for low-grade iron ores is provided, including upgrading low-grade siderite, limonite, micron sized haematite and magnetite resources.

Jan 1, 2009

By A Scrase, J Brereton

The Latrobe Valley is located approximately 150 kms east of Melbourne. Within a very small area there are 3 large brown coalmines and associated power stations, 3 large towns, and numerous smaller towns in the vicinity. The mines have been generating power for Melbourne and surrounds for the last 100 years, with two of the mines being owned and operated by the Victorian Government (State Electricity Commission of Victoria) prior to privatisation in the 1990s. All three mines were privatised with the expectation that the mine voids would be filled with water to become pit lakes, as the final landform/rehabilitation solution (Hazelwood Mine Fire Inquiry, Teague and Catford, 2016). It could be argued that until relatively recently, this was largely expected, by government and industry, to be the rehabilitation solution for managing the two key risks associated with the sites:  The geotechnical stability of the mine pits.  The prevention of fire – through covering coal batters with water. Transitioning away from mining economies requires collaborative, regional, innovative thinking with a multitude of stakeholders, from a wide range of government departments, industry, First Nations people and broader community. Closure planning and rehabilitation activities require a range of skills and experience, such as, closure planning, various scientific and engineering disciplines (pit water quality modelling, geochemical modelling, cover design, landform design, contaminated site etc), civil engineering, demolition etc. Some of these skills are similar, such as financial modelling, stakeholder engagement, contract and project management. But the majority are different to those required during the operational phase of a mine. These closure skills can also be lacking within government, with Departments more familiar with monitoring and compliance activities associated with operational facilities. Some key aspects that appear to be critical to planned successful closure are:  Collaborative regional and localised planning, with industry, government, community, First Nations and other industry, business leaders and entrepreneurs all involved in providing a smooth transition away from mining.  Well-defined and known regulatory pathways to achieve mine licence relinquishment assists in encouraging investment.  Appropriately skilled and experienced government and industry personnel.  Mining companies, who are committed to closure planning and provisioning from the earliest point in project planning.  Mine employees who are appropriately skilled and experienced in mine closure planning and implementation with access to all the relevant technical expertise required for the project. Areas like the Ruhr Valley in Germany provide good some examples of smooth processes that facilitate mine economies transition into new economies (World Resources Institute (WRI), 2021).

Aug 2, 2023

By J Sykes, W Treasure, A Saleem, A Trench, S Ulrich, R S. Davies

Below-ground technical complexity remains a traditional source of project challenge. Above-ground challenges then augment this complexity, including in the domain of commodity marketing. All challenges must be solved to produce quality, saleable, ex-mine product. The situation is further complicated in that technical complexities are not independent of each other, so complexity is best regarded as a system rather than a series of isolated factors. Additional above-ground challenges to mining projects are also increasingly sourced from societal and environmental factors, locally and globally. These challenges not only confer project complexity, but have their source in larger, global wicked problems. Finally, financing and resourcing of projects represents an ever-present challenge for all but the highest-quality mineral deposits. CITATION: Trench, A, Davies, R S, Saleem, A, Sykes, J, Treasure, W and Ulrich, S, 2018. On the sources of complexity in contemporary and future mining projects, in Proceedings Complex Orebodies Conference 2018, pp 65–66 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

By B J. Monaghan, R J. Longbottom, D J. Pinson, S J. Chew

Recycling steel plant by-products is a critical issue for achieving both environmental and economic sustainability of integrated steel plants. A key steel plant by-product stream is dust from basic oxygen steelmaking (BOS), which can be recycled back to the BOS vessel as iron units and to aid slag formation. The major limitations for its recycling are zinc and the uncertainty in zinc speciation of the dust. This uncertainty affects the amount of dust recycled and how it interacts with the slag during processing. BOS dust in stockpiles can undergo self-sintering reactions that oxidise the iron-bearing components. As this occurs, zinc (or oxide) may combine with iron oxides to form a zinc-iron spinel solid solution phase. Knowing which zinc-bearing species are present in the BOS dust is a key aspect in understanding and developing an efficient recycling process for the dust. To overcome difficulties associated with phase identification in the BOS dust (both fresh and selfsintered), particularly the magnetite-zinc ferrite spinel solid solution using X-ray diffraction (XRD) / scanning electron microscopy (SEM) / energy dispersive spectroscopy (EDS), high end characterisation tools, transmission electron microscopy (TEM) and Mössbauer spectroscopy, were also used. Such an approach allowed improved phase identification of key zinc- and iron-bearing phases that were not previously resolvable. The zinc in fresh BOS dust was mostly present as extremely fine separate particles of zinc oxide, attached to the iron particles. These extremely fine particles were <10 nm in size. Additionally, a small amount of zinc ferrite was also identified within the sample (most likely contained within a magnetite-zinc ferrite spinel solid solution). However, the zinc in the self-sintered BOS dust, was found to be present entirely in a magnetite-zinc ferrite spinel solid solution. While this spinel phase had been previously identified by XRD, it was not clear that it contained zinc. The Mössbauer results provided definitive evidence of zinc within the spinel phase.

Jun 19, 2024

By G Corder

The aim of the circular economy is to accelerate the transition from a conventional linear take-make-dispose economic model to a circular model. It is restorative and regenerative by design and aims to keep products, components and materials at their highest utility and value at all times. This extended abstract presents a brief overview of the circular economy, provides application of the circular economy in other industrial sectors including the downstream metals value chain and proposes how circular economy thinking could progress the development of complex orebodies.CITATION: Corder, G, 2018. Can the concept of the circular economy help unlock complex orebodies?, in Proceedings Complex Orebodies Conference 2018, pp 8–10 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

The main features and recent developments in the processes of benefication and extractive treatments of tin ores are reviewed. The need for development of processes to recover fine tin, tin from low-grade complex ores and from hard rock resources is indicated. The progress in understanding of slag-metal interactions and developments of fuming processes on industrial scale is delineated. the processes and prospects of hydrometallurgical and chlorination methods are briefly indicated.

Jan 1, 1992

By Marwick PL

As part of its operations Hamersley Iron operates a heavy medium Concentrator to upgrade low grade, unsaleable iron ore to produce saleable lump and fines products. Firstly, the attempts at delivering a blended feed in both chemical and physical characteristics are presented. Improvements in blending controls are shown to have given process performance improvements. Secondly, improvements to the feed preparation section are detailed. These alterations are providing a much cleaner feed to the subsequent processing stages.

Jan 1, 1987

Nauru Phosphate, which is one of the world&apos;s highest grade deposits discovered to date, contributed in 1969, 2.2 million tons of the total world production of 77.7 million tons. Phosphate production, which is the major source of revenue for the island nation, is carried out by the Nauru Phosphate Corporation, headed by a Government appointed Board of Directors. The complete mining operation, including ship loading techniques, is discussed along with proposals at present being investigated to upgrade the Quality of the product.

Jan 1, 1971

Supergene nickel sulphide ore mined currently by Agnew Mining Company is at times partially oxidised to sulphate. The resulting soluble nickel, and calcium and magnesium in mill water, are shown to act as depressants in flotation. The depressant effect is favourably selective in that violarite, the main nickel mineral, is less affected than pyrrhotite. Nickel recovery, however, is adversely affected, probably through reduced flotation of complex sulphides. Soda ash consumption is increased markedly by the presence of the cations as shown by operating data and pulp titration tests. A significant increase in concentrate grade, from 9% to 14% Ni, was achieved late in 1981. One of the changes in plant practice which contributed to this improvement was the addition of soda ash to mill feed rather than to flotation feed as before. It is shown by laboratory tests that this reduced the depressant effects of the cations, thereby improving recovery at the expense of rougher selectivity, or equivalently, increasing concentrate grade at constant recovery. The selective depressant effect cannot be exploited until scavenger recovery is improved and a scavenger concentrate regrind-retreat äcircuit is implemented. Development is

Jan 1, 1978

By Lemberg D. W, Friday R. G

Potential means of lowering overall costs to permit deeper stripping include : 1. the use of larger diameter blastholes in highly-fissured strata (to reduce drilling costs); 2. dewatering from semi-permanent bores to reduce blasting costs (by maximising the use of bulk ANFO) and promote highwall stability; and 3. the use of inclined blastholes, bulk AN, staggered V1 patterns, adequate backfill and more cost-effective stemming columns. Each of these is covered. The pumping of bulk watergels continuously raises the blasthole water column, thereby perpetuating the demand for these blasting agents. This must be a principal consideration when choosing between a bulk and a packaged watergel. Any packaged product should exhibit dimensional permanence and an energy yield per metre length equal to that of bulk ANFO. Possible ways in which controlled trajectory blasting (CTB) could benefit deeper stripping operations are outlined. By allowing the maximum use of bulk ANFO, de- watering may be a prerequisite of a viable CTB Operation.

Jan 1, 1981

By A Golsby

Both primary and secondary ventilation is important in underground mining. Secondary ventilation refers to the provision of ventilation to development ends, stopes and services facilities, which constitute secondary circuits tapped off the primary circuit or main through flow of air.An unbalanced primary and secondary combination can cause re-circulation, which is inefficient and potentially hazardous. These inefficiencies extend into operational and other considerations, such as power.Most cost justification analysis covers capital and physical consumables. These analyses are often not comprehensive or holistic. This case study is an example of ‘how to holistically justify’ a secondary ventilation circuit and optimise it to meet all stakeholder needs.This paper particularly addresses the following:how to account for all stakeholders in a secondary ventilation cost justificationthe secondary ventilation componentsthe cost justification outcomes and how to measure themsome of the sensitivitiesthe stakeholdershow to present the justification to meet the stakeholder needssecondary ventilation cost justification.CITATION:Golsby, A, 2015. Secondary ventilation as a value proposition – a case study, in Proceedings The Australian Mine Ventilation Conference, pp 49–54 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 31, 2015

By A L. Hemphill

Conventional models, based on pulp kinetics, were regressed directly to steady-state data from a nine-stage platinum flotation plant, to provide a basis for optimisation studies. æFroth factorsÆ were used to characterise the froth in each stage and a ædepressant factorÆ was used for gangue minerals, to account for addition of depressant to the cleaners. These factors improved the fit, but differences between plant and model of up to 50 per cent were still present in a number of streams in the cleaning circuit. A new model was developed, which incorporated two rate constants for the recycle of particles from the froth. These parameters provided a workable approximation of the distribution of probabilities of particles being recycled in plant cells, depending upon where particles appeared at the surface. The feed streams were characterised by two pulp kinetic parameters and the above recycle parameters, for all minerals and all stages. The fit to the data was improved very significantly, when compared to the use of conventional pulp-based models with several pulp rate parameters. This relatively simple model did not require additional data from batch tests and it was suitable for plant simulations.Simulations of various strategies for plant operation were tested, allowing the simulator to vary the concentrate flows from all or some of the stages, in order to maximise platinum recovery. The simulator was imbedded in an automatic optimiser and constraints on chrome content or mass flow of final concentrate were used. The simulations of the existing circuits demonstrated that an improvement in recovery, (for a constant concentrate mass) of about 0.5 per cent was possible, by optimising all concentrate flows. A significant reduction in the flow of scavenger concentrate and an increase in the recycle flows in the cleaners were noted. The results of simulations of various changes to the circuit configuration are also discussed. An increase in recovery of 1.4 per cent (for constant concentrate mass) has been achieved in recent simulations, through circuit changes. However, it was necessary to keep the mass pull of concentrate, per unit area, within typical limits.

Jan 1, 2005

By Dobos SK, Gibson GM, Little TA, Sliwa R

Current studies, and analysis of previouslypublished data, have lead to a re-evaluation of the inclusion of the North D&apos;Aguilar block within the "Gympie Province" in southeast Queensland. The metamorphic rocks are part of a Late Devonian(?)-Early Carboniferous subduction accretionary complex and are unconformably overlain by volcanic and coarse-grained clastic rocks of probable Early or mid-Permian age, as well as by Early to middle Triassic rocks of the Esk Rift. Metamorphic fabrics in the basement rocks include not only those that can be related to convergence, but also younger fabrics that may have developed during Late Carboniferous or Permian uplift and unroofing of the accretionary rocks. A predominance of basic schists, some of which are blue amphibole-bearing, and associated fine-grained pelagic and hemipelagic sediments in the Northern D&apos;Aguilar block contrast with the siliciclastic-dominated sediments of most of the accretionary complexes of the New England Orogen. However the similarity of structural style, and metamorphic and igneous history, with adjacent basement blocks, and with other blocks throughout the New England orogen, suggests that the North D&apos;Aguilar block simply represents deeper, probably underplated, levels of the same subduction complex. Uplift and cooling may have been accomplished by extensional faulting during Permian inception of the Esk rift, which flanks the block on the west.

Jan 1, 1990

Mining of the Martha Hill epithermal gold deposit via open pit methods will excavate a pit to 15 m below sea level. Regular geotechnical evaluations of pit slopes have taken place. Details of the various components of these evaluations, including geological structure, material strength, and groundwater, are covered. Pitwall geological structures are represented clearly on pit floor grade control maps with the dominant sets being steeply dipping strike fractures. Cross cutting shears are common. Material strength is reflected by the oxidation status of the hydrothermally altered host rocks, with weaker material occurring in partially oxidised ground. Regional groundwater is generally high, particularly on the north-eastern side of the pit, where it has been little affected by de-watering. Geological structures appear to control the flow of groundwater in the proximity of pitwalls and require draining by the introduction of horizontal drains. An overview of pit slope design is given. Slopes are designed for overall slope stability, allowing for the occurrence of minor interbench failures.

Jan 1, 1991