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By S Dunham

A cross-discipline approach combining geology, metallurgy and mine planning, geometallurgy is seen as the next logical advance in improving the design and operation of mining businesses. This rapidly evolving field is focused on realising the value that has often been lost in the chasms between the aforementioned technical silos. When successful, the geometallurgical approach promises the ability to tailor mining and mineral processing development and operational options more closely to the characteristics of the resource with resulting lower costs (both capital and operating), improved recoveries and fewer project failures.As with any technological (or managerial) change, there will be side effects from the success of the geometallurgical approach that will impact areas beyond obvious linkages between geology and processing. Some of these effects have the potential to be beneficial to the resource industry and society in general. Beyond the basic geometallurgical promise of closer alignment between processing design/strategy and the multivariate 3D spatial characteristics of the mineralisation, this paper discusses the broader implications and ramifications of the emergent geometallurgical approach: enhancing exploration and discovery; improving project development success; achieving sustainability in an industry working with non-renewable resources; in a world of increasingly hard won license to operate, improving the management of potentially harmful by-products and waste materials (with knock on effects for proactive management of closure issues); smarter approaches to energy management and thus optimisation of projects with respect to carbon footprint; and potential to re-value assets and thus realise a strategic advantage in the area of acquisitions, divestments, mergers and take overs. The authors strongly believe that companies that actively engage with the above issues (and ensure that technical efforts in the area of geometallurgy are not isolated from the larger value chain activities of the firm) will be able to exploit the opportunities that consequentially arise. These early adopters will gain first mover advantages. Firms taking the broad view of geometallurgy will have an opportunity to maximise stakeholder value and win greater success than their less insightful competitors.

Sep 5, 2011

By M Player, R Klug, N Schwarz

There are several technologies available for thickening and dewatering of mining process slurries. The most commonly used are thickeners and filters, but technological developments have made solid bowl decanter centrifuges a viable option and their use, as a modern and alternative technology, is being considered more and more. In terms of tailings, the main goal for all mine operations is to minimize operating costs and the environmental impact of the disposed material. The high potential risk of wet tailings storage in tailings dams is causing this technology to become unpopular, and there is a strong drive in many parts of the world, by governments, communities and environmental agencies to limit any further construction and use of such facilities. For the alternative disposal method of dry disposal of tailings, two aspects of the process have to be evaluated, namely the maximum dryness of the separated solids and the maximum liquid recovery. For most mining operations dry disposal is a new concept. Presenting these companies with examples of operations where this processing option has been successfully applied and proven, will help them to adapt to the changing requirements in the future. Focus has been placed on adapting decanter centrifuges to the mining environment. Modern decanters stand out in terms of their small footprint, low water demand, high availability and their high degree of automation, combined with the excellent cost / performance ratio. Decanter centrifuges have started to play a key role in applications such as tailing dewatering, drilling and tunnelling muds processing, hydrometallurgical processes of gold, nickel or zinc and separating crud in solvent extraction plants. This paper will present advantages of decanter centrifuges compared to the traditional technology and corroborate these advantages by case studies.

Jul 1, 2021

Determining the controls of high-grade mineralisation at Vera Nancy requires careful data collection and assessment on a global and specific deposit basis. The techniques developed over 60 years ago to analyse structure, grade and width data are just as applicable today and can be enhanced using modern geological modelling software. High ore grades at Vera Nancy are controlled by both the primary geometry of the mineralised structure and the intersections of the main mineralised veins with subordinate splay veins. The main mineralised structure dilated as a consequence of extensional tectonics while the splays acted as conduits bringing oxidising surficial fluids into mixing zones precipitating high gold grades. Near-mine exploration is focussed on identifying zones of vein flexure and splay interaction to locate the relatively small high-grade shoots. Data modelling in a 3D environment is an essential process for understanding the geometry of the system being explored.

Jan 1, 2000

By Reichman J. P

Extensive use is made of a small scale computer (IBM 1130), in the calculations of ore reserves for Western Mining Corporation's nickel mine at Kambalda, W.A. All surface drilling data such as assays, density and location information, are stored on disk files at the Company's Technical Computing Centre at Perth, W.A. The computer is used to search through the data, select significant ore intersections, calculate the area of influence of each intersection and perform the necessary calculations to arrive at an estimate of the ore reserve. Comparing the computer-assisted ore reserve calculation with an entirely manual operation, it is estimated that a saving of 40 percent in time is achieved together with

Jan 1, 1973

By J P. Wyethe, D P. Padayache, B R. Green

The development of an ion exchange process for the recovery of vanadium from solutions containing low concentrations of vanadium and/or slurries is discussed. The process can be used to improve overall vanadium recovery throughout the plant, and/or to reduce the vanadium concentration of waste materials prior to their disposal. The development of the process on a laboratory and miniplant scale is discussed, and includes:selection of a suitable resin with the desired loading and elution characteristics; laboratory-scale testwork to evaluate the use of the resin in both resin-in-pulp and fixed bed configurations; recovery of a high-value vanadium product from the resin eluate; and a preliminary techno-economic assessment of the financial viability of the process.

Jan 1, 2000

By A Roshal

It is anticipated that many future uranium mines in Australia will be using the in situ leaching mining process. It is fair to say that close to one third of uranium production will be generated by this method, whilst the other two thirds will fall on the uranium generated from hard rock mining and other mining methods, such as traditional open cut mining. For other types of deposits the in situ leaching mining method will remain the best technological, commercial and environmental alternative. It is important to identify and prevent all risks involved in uranium mining. The expertise in this subject is limited. Over the years there was only one mine using the in situ leaching process for uranium extraction in Australia. Computer simulation of propagation of leachate during and after the uranium in situ leaching is a crucial factor, not only for addressing the environmental concerns, but also for the most efficient recovery of the deposit. The decontamination can be modelled for a period of up to 100 years, with the acid neutralisation forecast for a period of up to 400 years. The results of the modelling are paramount for definition of the reserves, efficiency of the mining method and the environmental impact statement. The accuracy of the hydrogeological modelling and carefully selected environmental management program enables a mining company to quantify and minimise the impact of the mining activities on the regional aquifer and to prevent environmental disasters. In the study, the completed hydrogeological model allowed the client, the authorities and the community to make an informed decision about the environmental impact of the in situ leaching of uranium. In particular, the model proved that neither during the mining, nor during the neutralisation the toxic elements would interact with the local catchment area.

Jan 1, 2008

By S R. Grano, M Vera

This paper deals with two separate case studies investigating the froth phase performance and characterisation of two industrial rougher/ scavenger flotation circuits. Froth phase performance was quantified using a mass balance approach to estimate froth zone recovery. Measured characteristics of the froth phase included frother solution concentration determined by gas chromatography, and the time taken for an equilibrium froth sample to decay to one-half of its original froth height. The latter measurement is referred to as the æfroth half-lifeÆ and is strongly linked to froth stability. Special methods and techniques developed to preserve frother in solution and to measure froth half-life are briefly described. The frother type in the first case study was a mixture of straight and branched alcohols, whilst the frother type in the second case study was a mixture of alcohols, aldehydes and triethoxybutane. The first case study focussed on a flotation circuit treating a low-grade ore containing only a small fraction of floatable copper sulfide minerals, while the second case study focussed on a flotation circuit treating a higher grade complex sulfide ore containing significant quantities of chalcopyrite, galena, sphalerite and pyrite. It was found that froth zone recovery of valuable mineral generally decreased down-the-bank of the two industrial rougher/scavenger circuits. Moreover, decreases in froth zone recovery significantly limit the overall cell recovery of valuable mineral achievable from the plant scavenger cells. However, the decrease in froth zone recovery could not be linked to the removal of frother from the pulp solution to the concentrate product in the preceding rougher flotation stages. Measurements of residual frother in solution suggested that, approximately, only five to ten per cent of the added frother was removed into the rougher/scavenger concentrate, with the remainder appearing in the scavenger tailings. This finding suggested there was apparently adequate frother in solution in the scavenger stages.

Jan 1, 2005

By D Connelly

Magnetite ores can be used to produce very high-grade concentrates that are suitable feed for the direct reduction process route but the high sulfur content of some concentrates can cause substantial environmental issues. Processing of high sulfur magnetite ore is therefore increasingly problematic for the industry. Generally, the industry demands a concentrate with <0.05 per cent sulfur and <2 per cent silica. This paper reports the outcomes of a study to produce a concentrate with the requisite low sulfur content from a sulfur-rich magnetite ore. The main findings may be summarised as follows: if the sulfur is present in magnetite as nonmagnetic pyrrhotite or pyrite, it can be beneficiated using magnetic separation and hence, monoclinic pyrrhotite is magnetic and is magnetically recovered with magnetite leading to a concentrate that is too high in sulfur. X-ray diffraction and QEMSCAN analyses revealed that the magnetite concentrate was liberated at P80 30 microns and was associated with maghemite, pyrrhotite (magnetic), carbonates and hematite with very low amounts of chalcopyrite, sphalerite and arsenopyrite. Sulfur removal using flotation was the first stage of investigation and this required flash flotation in the grinding stage followed by column flotation of the initial concentrate to generate the final concentrate. At the same time, it was observed that oxidation of the pyrrhotite had a negative effect on its flotation requiring copper sulfate to activate it. Bioleaching and concentrate leaching were also considered and achieved over 90 per cent sulfur removal but were deemed unsuitable owing to the production of highly reactive wastes and high CAPEX. Reference is made to a number of operating magnetite producers and how they manage the sulfur in feed.

Sep 18, 2023

By B Putland, I Lovatt, D Schwann, A Cervillin

The Mount Carlton project in Queensland&#39;s North East sits on a high-sulphidation epithermal style deposit rich in gold, copper and silver. Mt Carlton is an open pit mining operation with ore processed using a primary crusher, single stage SAG mill and flotation to produce a concentrate for sale. Orway Mineral Consultants (OMC) was involved in the original design of the comminution circuit and the project was commissioned in late 2012, with first concentrate shipped in March 2013. When Evolution sought to optimise the project in 2015, OMC was invited to assist by undertaking a circuit review to identify opportunities for the optimisation. During 2016, the Mt Carlton site team implemented the optimisation strategies developed in conjunction with OMC. These included reconfiguring the SAG mill discharge arrangement, reducing the average ball diameter and allowing the mill to operate at higher speed and under more autogenous conditions. Cyclone operation was changed to constant pressure and the vortex finder size was decreased. The combined strategies improved energy efficiency and allowed higher SAG mill power utilisation. The additional power has been used to increase throughput by 2.4 per cent while achieving a 27&#181;m reduction in product size (P80) to gain downstream recovery improvements. The reduction in grind size has been achieved with only 6.8 per cent increase in specific energy consumption because of a 6.5 per cent increase in grinding efficiency. The circuit product size is also notably more consistent due to the improvements made to the cyclones, providing benefit to the downstream flotation circuit. A significant decrease in ball consumption was also gained, saving hundreds of thousands of dollars a year in operating cost.This paper will discuss the circuit design, start up and will detail the changes made during the optimisation and why these were successful.CITATION:Putland, B, Lovatt, I, Cervillin, A and Schwann, D, 2018. Mount Carlton comminution circuit design, start-up and optimisation, in Proceedings 14th AusIMM Mill Operators&#39; Conference 2018, pp 517–528 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018

Although the last decade has seen the growth of many new licencing and approval requirements for the exploration and mining industries, there remains in each State of Australia and the Northern Territory a predominant "Mining Act" containing provisions for the grant of exploration and mining tenements. What then are the rights and duties of tenement holders either by virtue of a Mining Act or through other approval and licencing mechanisms? What rights and duties does a person acquire when he is granted an exploration licence or a mining lease? In this paper I will attempt to cover these types of questions using in particular examples from New South Wales. I will also refer to a range of other subordinate approvals and licences which today&apos;s society requires and the need for ethics and recognition of liabilities.

Jan 1, 1995

The following is a brief summary of the Bulli Colliery and its method of operation when Australian Iron and Steel Ltd. took control.Bulli Colliery is situated about a mile west of the village of Bulli and is some 10 mUes north of the Australian Iron and Steel Company&apos;s Steelworks at Port Kembla.The mine is owned by Australian Iron and Steel Limited, who purchased it in 1936 from the liquidators of Bulli Colliery and Coke Works.It is one of the oldest working coal mines in Australia, having been opened about 1858 and has worked more or less continuously since that date.The seam worked is the No. 1, or Bulli, Seam, which outcrops along the escarpment of the Illawarra Range and is generally operated by tunnels, the portal at Bulli being some 440ft. above sea level.The colliery holding is fairly extensive, but the coal seam over a large portion of the area within two miles of the outcrop has been more or less destroyed by an intrusion of basalt.At present there is no coal being worked within a distance of about 21 miles from the surface, the farthest workings being about four miles from the tunnel mouth.The existing main haulage road, for the first two miles from the portal, is not straight; it is very narrow over fairly long stretches and has many changes of grade varying from 3% in favour of the load to 13% against the load.The dumping station and screens are situated close to the portal of the haulage tunnel, and at this point the coal is loaded into railway hopper waggons, which are then hauled by rope to the top of a self-acting incline. The waggons are lowered down the incline, a distance of approximately! mile, the ruling grade being about 18 %.From the bottom of the incline, waggons are hauled by Company&apos;s steam locomotive to exchange sidings from whence they are taken by New South Wales Government Railway engine to the Company&apos;s Steelworks at Port Kembla.

Jan 1, 1947

By P Murthy, Z Guan, P Townson

In this paper, we introduce a methodology to optimise mining equipment operation in terms of the conflicting concerns of productivity and availability. We also introduce the concept of damage points and equipment dutymeters. These provide the mine management with tools to monitor the success of such optimisation. Since we have quoted the results of an on-going Australian Coal Association Research Program (ACARP) project, the apparent focus of this article is on draglines. However, the concept is equally applicable to other equipment. Mining is the type of business that requires a large investment in capital infrastructure and equipment to produce a product that is sold at a relatively low unit cost. In such a business, the key to competitiveness lies in achieving the full realisation of capital investment ie sustained production at high levels. Some of the concepts outlined in this paper are essential components of this picture.

Jan 1, 2000

By T N. Little

The grade control process undertaken at mines aims to maximise the value of the ore (valuable product) mined and fed downstream for processing or sale. The full range of grade control activities includes: reserve estimating, drilling/sampling, assaying, modelling, ore block design, blasting, ore mark out, excavating, stockpiling, processing and reconciling. Over the last 25 years, the grade control process has undergone significant improvements and this is in part due to the developments in grade control blasting. This paper discusses the development and classification of grade control blasting applications in surface mining. A review by the author in 1988 (Little and van Rooyen, 1988) is used as a benchmark for discussing the very significant progress that has been made.Two major technology initiatives have enabled this development. The first was the development of a method for the measurement and analysis of total displacement during the blasting process. Currently, the Blast Movement Monitor (BMM&#174;) is a practical tool that has been used around the world to improve the industry’s understanding of three-dimensional blast movement dynamics. The second technological enabler was the development of electronic detonator systems. The unique aspects of electronic detonating systems are their higher accuracy and that all detonators are activated at time zero (initiation). From a grade control blasting perspective these features and other improvements allow experimentation and, ultimately, more complex, multiobjective blasts to be designed and implemented.This paper reports on a classification and review study undertaken by the author. In all, five selective blasting methods and nine bulk blasting methods are classified and reviewed. Five important observations are made: there is value in classifying the range of grade control blasting strategies, and the blasting objective framework presented is helpful in this regard the range of strategies available to designers is increasing as enabling technology develops, so too do the ambitions of blast designers and the expectations of downstream customersgrade control blasting and Mine to Mill concepts are merging, and this paper caters for this trend using multiple blasting objectiveshaving a technical primary blasting objectives framework, combined with the classification system presented here, should assist practitioners and stakeholders with lateral thinking in regards to future technological innovations, grade control blasting and Mine to Mill initiatives.CITATION:Little, T N, 2015. Classification and development in grade control blasting for surface mines, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 343–354 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

Sasol Roche Blasting Services (SRBS) and its former owners have been in the process of developing and utilising low-density explosives over the last ten years. Many blasts have been fired in varying strata types in a number of mining operations. This has led to a good understanding of the product and the best methods to exploit its characteristics when designing blasts. Unlike some other low-density products, SoftLOAD« is a homogeneous mix that is easily handled and able to be loaded at high load rates. This paper discusses the physics of SoftLOAD« low-density explosives and how through correct utilisation, blasting outcomes can be significantly improved. It also touches on the various side benefits that can provide the blast designer with a more controlled blast.

Jan 1, 2004

By P Marianelli, J Theiler, B Beamish, A Spillman

The presence of reactive pyrite in waste rock contributes to the hazard of spontaneous combustion in emplacement facilities as it acts as an initiator of self-heating at low ambient temperatures. Organic carbon also present in the waste rocks acts as a fuel at elevated temperatures above 120&#176;C and can lead to thermal runaway resulting in eventual ignition. A new laboratory test method (adiabatic incubation testing) is now available that can identify the presence of reactive pyrite and quantify the self-heating behaviour of the waste rock. McArthur River Mine has a waste rock profile that contains pyritic shale units, which have created spontaneous combustion events in the past. A systematic sampling and testing program is underway to characterise the spontaneous combustion hazard likelihood of the McArthur River Mine waste rocks to provide a sound database for future mine planning of the waste removal and emplacement. This paper presents some initial outcomes of this program and shows the leading practice in spontaneous combustion hazard assessment and management that has been adopted at McArthur River.CITATION:Beamish, B, Marianelli, P, Theiler, J and Spillman, A, 2018. Spontaneous combustion hazard assessment of McArthur River Mine waste rock, in Proceedings Mine Waste and Tailings Stewardship Conference 2018, pp 422–426 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 23, 2018

By Gochin RJ

This paper focuses on measures of the economic significance of mineral exploitation and processing activities, such as beneficiation, refining and smelting. Empirical measures are suggested to quantify the relevance of the degree processing within a nation&apos;s mineral industry. The most useful, based on the input-output econometric framework, are used to establish the magnitude of links between the mineral industry and its satellite activities and for the appraisal of large, non-marginal projects. The input-output impact analysis is refined to allow for country specific behaviour and synthetic indices for the appraisal of investments in the mineral sector are developed. These indices are further improved with the introduction of shadow prices to incorporate socio-economic issues. They are useful to direct mineral policy decisions and several investments towards the most promising objectives for national goals. Finally traditional methods for the appraisal of small scale, marginal, mineral projects are assessed where local impact and regional development issues are more relevant than national ones.

Jan 1, 1993

By McQuade C. V

Mining is an activity which has, in the past, been regarded as often leaving land in a condition unfit for further use. As the need for development that is both economic and ecologically sustainable has grown, so the issue of re-use of land after mining has become significant. During operation it is usual that mine environmental conditions which minimise unnecessary or avoidable environmental impact are agreed with the regulatory authorities . These conditions are usually set down in such a way that they can be interpreted reasonably well by both miners and regulators. However, the conditions to be met by a mining company before it can be absolved of responsibility of a site are often less clear. The close-out criteria by which the success of rehabilitation programs will be judged have received little attention in the past. These conditions are now growing in importance as the costs of rehabilitation of a mine site to an agreed post-mining land use assume greater significance in the economics of mining. This paper briefly describes the status of close-out criteria presently being applied across Australia. A comparison is made with similar guidelines from other countries.

Jan 1, 1994

Carbon sequestration in planted forests provides an immediately available, low cost option to address the greenhouse impacts of coal mining and coal utilisation in a carbon constrained world. In addition, planted forests also offer the opportunity to address other environmental issues, particularly salinity and loss of biodiversity. Given salinity is characteristically associated with agriculture in the 500 to 700 mm rainfall belt, then where such forests can also produce commercial timber products, they offer the additional opportunity to establish new, diversified rural employment in both timber growing and processing. In the majority of Australian catchments affected by salinity, where rainfall is generally less than the 700 mm limit to conventional forestry, and where groundwater reserves are often saline, the objective of achieving economically viable forestry production presents a significant challenge. In 1996, Saltgrow commenced a collaborative breeding program to combine the salt and stress tolerance of E camaldulensis, with the growth rate, stem form and wood properties of the commercial species, E grandis and E globules. This program aimed to produce trees with the potential for commercial rehabilitation of saline landscapes. Results covering a range of site conditions from SaltgrowÆs network of over 100 trials around Australia are presented. The opportunity for commercial plantations integrated with agriculture in low to medium rainfall areas to address salinity and sustainability will be discussed. In addition, the significant potential for partnerships between land-rich, cash-poor farmers, catchment management authorities seeking to invest in public good projects that enhance environmental sustainability, and major carbon producing industries with either mandated or voluntary requirements to curtail net emissions will also be discussed.

Jan 1, 2005

By P N. Nkrumah, A van der Ent, G Echevarria, P D. Erskine

Nickel phytomining is a low cost alternative to traditional nickel mining and a complementary process to existing mining operations in areas with low-grade nickel soils or nickel waste material. The process of nickel phytomining consists of growing selected hyperaccumulator plant species (‘metal crops’) on Ni-rich (ultramafic) soils, followed by harvesting and incineration of the biomass to produce a ‘bio-ore’ from which Ni salts or Ni metal may be recovered (Chaney et al, 2007). The ‘metal crops’ are selected on the basis of high biomass yield combined with high Ni concentrations (&gt;1 per cent) in the above-ground biomass (Chaney et al, 2007). Currently, Alyssum murale and A. corsicum have been used for Ni phytomining trials, mainly undertaken in Albania and USA (Bani et al, 2015; Li et al, 2003), while the agronomy of &lt;10 species has been tested in temperate regions (Nkrumah et al, 2016). Nickel phytomining has high economic potential; however, large-scale demonstrations are needed to provide ‘real-life’ evidence for commercial operations (van der Ent et al, 2015). Unrealised opportunities exist in tropical regions for commercial scale Ni phytomining. To date, the agronomy of tropical ‘metal crops’ has not been tested. This extended abstract presents the progress of tropical phytomining, and reports on agronomic trials undertaken to determine whether the trends in temperate regions could be confirmed in a wet tropical environment.CITATION:Nkrumah, P N, Erskine, P D, Echevarria, G and van der Ent, A, 2016. Progress in tropical nickel phytomining, in Proceedings Life-of-Mine 2016 Conference, pp 135–137 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By A Vakili

Dilution is associated with considerable direct and indirect costs in underground open stoping operations. As shown in previous works, an improved ability to predict dilution enables the economic risks associated with unplanned dilution to be reduced. Depending on the width of the orebody and depth of mining, the economic performance of an open stoping operation can become even more sensitive to dilution. It is shown in several well-documented studies that as little as 1 per cent of additional dilution can impose millions of dollars of lost profits per annum. Optimisation of a stoping operation is therefore largely dependent on the ability of the operation to minimise dilution. This can only be achieved through sensible analysis of past and future performance of mined stopes using the most appropriate recent available technologies and tools. This article presents a new design process that utilises advanced geotechnical numerical modelling and various other analytical tools to assist with a more robust mine design of open stoping operations. The focus of this design process is on geotechnical factors affecting dilution during the life-of-mine. A recent application of this optimisation method for a mining operation is presented in this paper as a case study. Through the application of this method and various other operational improvements, the mine was able to deliver more consistent production and lower operating costs over its life-ofmine outlook and was able to reduce dilution by up to 50 per cent and achieve sustainable record high production rates.

Mar 29, 2023