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By D Felipe, G J. Harbort

In the past 40 years substantial changes have occurred in flotation machines. This has included increases in mechanical cell size to 630 m3 , significant changes to flotation column aeration design and widespread use of the Jameson cell and other pneumatic flotation cells. Over the corresponding period there has been increased used of machine characterisation measurements to benchmark and optimise flotation circuit performance. JKTech maintains a database of industrial flotation machine characterisation measurements. The database contains over 4000 entries and includes gas dispersion measurements, such as bubble size, gas hold-up and superficial gas velocity, cell dimensions and impeller tip speeds. Data comes from numerous operating sites and commodity groups, including gold, copper, molybdenum, nickel, palladium, lead-zinc, platinum, silica, phosphate, coal and iron ore. Flotation duties registered include flash flotation, preflotation, roughing, scavenging and cleaner circuits. Measurements have been conducted on a wide range of flotation machines from different manufacturers. This includes forced air machines, such as Outotec and Dorr Oliver, and self-aerated machines, such as Denver and Wemco. The database also includes substantial flotation column entries, such as the Microcel, Eriez/CMT Slamjet and Jameson cell. This paper describes the flotation machine characterisation database and discusses the variation between different types of industrial flotation machines, in operating production circuits.

Aug 24, 2022

By D Horacek, I K. Sheppard

Ok Tedi is in a period of transition. By 2008 mill feed will consist of higher levels of high-grade but metallurgically challenging skarn ores. Additionally, the Taranaki pit will start production in 2008 along with the start-up of a new pyrite concentrator. Taranaki ores are very high in sulfur. Sulfur is captured in a pyrite concentrate prior to tailing entering the Ok Tedi River. These and other complex scheduling issues will need to be resolved over a critical three-year period. With these requirements in mind, Ok Tedi contracted AMC Consultants to develop a custom version of the Life of Business Optimisation System (LOBOS¬) to assist medium-term production scheduling at Ok Tedi. LOBOS utilities enable Ok Tedi planning engineers to:import polygon-based reserve data (Blast Masters) from MineSightÆs Interactive Planning Tools (IP Tools); graphically construct block sequencing and material flow constraints; edit constraints defining standard scheduling, processing and financial relationships; define dump and stockpile attributes; and assign capacities to production systems, plants, dumps and stockpiles. LOBOS converts Ok TediÆs production scenario into a mixed integer program (MIP) and submits the resulting model to IlogÆs Cplex MIP Solver. The Solver seeks an optimal production schedule that maximises net revenue per mill hour while meeting all constraints. This paper introduces Ok Tedi and its production requirements and relates these requirements to the facilities developed for an Ok Tedi version of LOBOS.

Jan 1, 2007

Renison Goldfields Consolidated Limited (RGC) and Consolidated Gold Fields Plc (CGF) purchased New Guinea Goldfields Limited (NGG) in 1982 as an exploration venture. Following an intensive drilling programme in the Upper Ridges area sufficient ore reserves were outlined to justify the installation of a new 700 tonnes of ore per day gravity gold extraction plant. Major considerations in the design of the new plant were to minimise production inter- ruptions in the existing plant and to include simple, but technically efficient, equipment that could be operated and maintained by a workforce with limited experience in modern technology. These goals were achieved over a six month period, commissioning being carried out in April, 1983. Mining the epithermal gold deposit is by open cut benching and truck haulage. The gravity concentrator includes a scrubber, wet hammer mill and rod mill, to crush, grind and prepare the ore for sizing and desliming. Gold recovery units consist of a jig, spirals, shaking tables and amalgam barrels. Although the majority of the gold is in the minus 100 plus 20 microns size fraction a recovery of 63 percent, from a head grade of 2.0g/tonne, is Achieved.

Jan 1, 1984

By S Fityus, K Koosmen, J Simmons

The purpose of this paper is to therefore investigate the hydrogeological characteristics of tailings, coarse and mixed rejects from coal processing to enable better understanding of the potential for undrained behaviours in coal mine spoil piles. This is achieved by analysing the results from permeability and oedometer testing of tailings, coarse rejects and mixtures thereof. Focus is given to the effect that tailings content has on the behaviour of mixed rejects, the transition point between drained and undrained material behaviours, and the evolution of properties with increasing stress that would occur with increased depth of burial in a mine spoil pile. The implications of the findings are discussed with respect to spoil pile stability.

Jul 1, 2021

By I M. Platten, Y Xie, R-M F. Bell, S C. Dominy, L E. Howard, R C. A Minnitt

For any resource evaluation program, the collection and processing of representative samples for assaying is critical. Sampling, sample preparation and assay protocols must be designed to suit the style of orebody in question. The a priori need is for the characterisation of mineralisation type(s) and domain definition. The proportion and size of gold particles has a direct impact on the effectiveness of sampling protocols employed. Mineralogical studies focusing on gold particle deportment, size and distribution are required. Key issues are the presence of gold particle clustering and proportion of coarse versus fine gold. High-resolution X-ray computed tomography (HRXCT) is a radiographic technique that produces high-resolution 3D computerised models of in situ objects based on density distribution. The ævirtualÆ specimens are made up of voxels, the 3D equivalent of pixels each assigned a grey value based on X-ray absorption. This paper presents the results of recent research on the imaging of in situ particles in coarse gold-bearing ore samples from the Nalunaq mine, southern Greenland. The samples used were previously well-characterised through mineralogical and metallurgical testing, and serve to test the HRXCT methodology. Gold particle size and distribution in the context of the sampling liberation diameter was investigated.CITATION:Dominy, S C, Platten, I M, Howard, L E, Xie, Y, Bell, R-M F and Minnitt, R C A, 2012. Determination of the sampling liberation diameter in a high-grade coarse gold ore by high-resolution x-ray computed tomography, in Proceedings Sampling 2012 , pp 161-170 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 21, 2012

By D R. Lueking

A technology involving separate unit processes for the generation and use of ferric ions for the oxidation of sulphidic minerals has been developed. The technology utilises a stand-alone automated bioreactor for ferric-ion generation (termed SAAB-FIG) and produces a low pH, ferric ion-rich leach liquor with a high oxidation potential. This leach liquor is then employed, in a separate unit process, to oxidise sulphidic minerals and regenerate ferrous iron that may subsequently be recycled to the bioreactor for the continual generation of ferric ions. The technique was successfully applied for the recovery of copper from chalcocite (Cu2S) and chalcopyrite (CuFeS2), as well as other ores and concentrates containing copper sulphide minerals. Coarse ore, ground ore and concentrates were treated with acidic solutions containing 8 to 12 (g/L) Fe(III) ions at a variety of temperatures. This process yielded over 50 per cent of the contained copper from both chalcopyrite and chalcocite samples. Maximum reaction rates and copper recoveries were found to be highly dependent upon temperature and pH and leach liquors containing bacterial cells displayed little difference in their leaching efficiency when compared to cell-free leach liquors.

Jan 1, 2000

By J Zhang, B Wei, T Zhao, K Wang

Understanding mining-induced surface movement and fissures is critical for environmental protection and geological prevention. In this study, image recognition algorithms, satellite remote sensing and unmanned aerial vehicle photogrammetry (UAVP) were combined to identify surface movement and fissures caused by mining, and a case study was conducted in a coalmine in western China, and the following conclusions were obtained.

Sep 1, 2024

By A G. Guinea

Every person in an organisation has what could be called ‘a different take’ on what it means to be a safety leader. The directors will tell you they are ultimately responsible for everyone’s safety and that they can be imprisoned as a consequence of a workplace fatality. Managers, take more of a focused approach and would explain that they are totally responsible for the safety of their teams. And then there are front-line leaders. Those that not only have the responsibility (like directors and managers) but they also have the accountability, and the ability, to influence how safely their teams work. But it is not just physical safety that leaders should be concerned with.

May 5, 2022

By G M. Taylor

The application of high technology to monitor and control fire life safety, critical functionality in tunnels and underground spaces generally has progressed at an ever accelerating rate over the past decade. Today these systems comprise some of the most complex and little understood aspects of the tunnel/underground facility construction industry, with this area being perceived as high risk comprising impenetrably complex ‘black box’ technology covered in blinking LEDs. This paper will seek to explode some urban myths and common misconceptions associated with such systems, providing its intended audience with a review of what all this technology comprises and where the real risks lie in its delivery lie.The author contends (and looks to support such contention via this paper) that by applying baseline project and risk management processes to the procurement of this widely misunderstood black box technology, the quality of the final outcome can be much improved, driving innovation, reducing both cost and significantly mitigating delivery risk.CITATION:Taylor, G M, 2014. Procuring control and intelligent traffic systems for major new build projects – avoiding pitfalls and maximising value, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 113–120 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By H Bao, M Nehring, M Kizil, P Knights

The mining sector, a notably energy-intensive industry worldwide, is a major consumer of fossil fuels, leading to significant carbon emissions globally. The move towards electrification, coupled with advancements in battery technology, has redirected focus from traditional diesel-powered solutions to battery-powered alternatives. This paper introduces a novel mining haulage system, termed the Battery Trolley system, and examines its theoretical foundations, configurations, and operational processes. It offers a comprehensive analysis of the system’s characteristics and limitations. Through a hypothetical road simulation, the study analyses various battery mining trucks, calculating energy consumption based on force parameters and tailoring battery sizes to contemporary materials and technology. When assessing various battery truck alternatives—considering aspects such as battery size, effective payload, duty cycle, energy efficiency, productivity, and single-shift production—a range of performance outcomes and characters become apparent within the mining context. The findings indicate that Battery Trolley configurations, requiring smaller battery capacities, entail lesser compromises on effective payload. Consequently, these configurations achieve a higher duty cycle, reduced energy consumption per tonne, heightened productivity, and enhanced singleshift production capabilities compared to Battery-only alternatives. The comparative analysis of Battery Trolley with stationary charging (BT-S) and Battery Trolley – dynamic charging (BT-D) underlines that battery Trolley systems are capable of overcoming the challenges associated with battery size, thus successfully fulfilling the production demands of large truck applications in mining. This positions Battery Trolley systems as a more advantageous option for the decarbonisation of mining fleets, underscoring their potential in contributing to the sector’s sustainable evolution.

Sep 1, 2024

By L E. Howard

Micro-computed tomography (Micro-CT) is an X-ray imaging technique that produces high-resolution 3D computerised ‘virtual’ models of geological specimens based on the X-ray attenuation of different materials in the specimen. The ‘virtual’ specimens are made up of voxels, the 3D equivalent of pixels, each assigned a gray value based on X-ray absorption. Micro-CT has enormous potential for allowing non-destructive, digital analysis of structure and composition when the mineralogical phases can be digitally separated. However, variation in X-ray flux between scans results in highly variable grayscale values for identical materials. Consequently, materials usually have to be segmented manually, which is subjective, inaccurate, labour-intensive and time consuming. Here we present a protocol and imaging software package that can be used to accurately and precisely extract quantifiable information in a repeatable and objective fashion. The software will allow the separation, visualisation, measurement and analysis of spatial and volumetric distribution of different mineral phases without damaging the specimen. This paper explains the potential use of this protocol and software package to ultimately allow automatic segmentation and quantification of gold in drill core samples, removing subjectivity and inaccuracies from data processing.

Sep 5, 2011

By Hart J. G, Anderson J. S

The presence of platinum metals in the nickeliferous copper ore of the Thomson River Copper Mine near Walhalla, Victoria, was first revealed in 1905 by assays made in the laboratory of the Department of Mines (1).These disclosed the presence in the ore of 5 dwt. platinum metals, 1 dwt. gold and 13 dwt. silver per ton. Attempts to isolate the platinum-bearing mineral were unsuccessful, and the absence of obvious native platinum led the assayer, Mr. P. G. W. Bayley, to suspect that the platinum might be present as sperrylite. Subsequently, Mr. C. M. Lyons, then metallurgist to the Long Tunnel Gold Mining Company, Walhalla, tried to isolate the platinum mineral from samples of ore containing as much as 7 dwt. platinum metals, but again without success.In 1912, a sample of copper matte from this ore was submitted to Messrs. Johnson, Matthey and Company, Limited of London, for analysis. The analysis, which is quoted below by their courtesy, revealed tnat a large proportion of the metal pi'eviously reported as platinum was palladium, there being about two parts of palladium in the matte to one part of platinum.

Jan 1, 1942

By M McCarthy

Over the last six years Mandalay Resources has increased production rates and improved safety outcomes at its Costerfield mine in Victoria, Australia. This mine is an underground operation utilising narrow mining techniques to extract vertical veins, and produces up to 80 000 equivalent ounces of gold per annum, in both gold and antimony value.The operational challenges of narrow vein mining include controlling overbreak when veins being mined are only 300 mm wide. The mine has developed methods and modified equipment to suit extraction of these veins. Productivity improvements over the period have involved development of a stoping method and equipment to suit 1.8 m wide development drives. Over the last five years and during a skills shortage, recruitment, training and retention of personnel has been key to keeping corporate knowledge and skills to execute a careful efficient mining technique to minimise overbreak.Managing an underground operation close to nearby residents has unique challenges. Historically Victorian residents had family members work as underground miners; however, in the current day with few underground operations in this jurisdiction, community knowledge of mining has decreased. The Costerfield Operations are only 100 m from the nearest residence and the company values community engagement, partnership and investment with local Heathcote organisations.The mine has invested substantially in executive coaching of its leadership team early, which has paid dividends in problem solving potential of that team and ensuring the operation delivers on its promises to all stakeholders. The operation has become safer and employees are now more aware of their individual contribution in producing safe, efficient gold and antimony that benefit the whole operation, community and the region.CITATION:McCarthy, M, 2016. Costerfield – a narrow vein case study, in Proceedings International Mine Management Conference, pp 331-338 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 22, 2016

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

By C A. Cooper, G A. Suter

The sizing of a starter dam for a Tailings Storage Facility (TSF) involves balancing many competing demands. It should cost as little as possible, be high enough to store tailings until the first raise can be constructed, it must be able to contain water safely, and it must be designed in such a way that the long-term integrity of the higher raises are not compromised, among other things. In addition to these demands there is the complication of the behaviour of the process plant, and the tailings during commissioning. Variations in slurry density, excess water in the TSF, initial settled density of the tailings, reliability issues, and beach slopes above and below water can all impact the way the tailings beaches are developed and ultimately impact the ability of the starter dyke to contain the required volume of tailings and water.The conventional approach to the design of a TSF starter dyke is to begin looking at the elevation required for a set of deterministic design parameters, find ways to reduce the size or volume of it as much as possible to reduce cost, and then possibly look at the sensitivity of some of the input parameters. This paper discusses a stochastic modelling approach for starter dykes that allows a wide range of design inputs to be simulated quickly, with an envelope of possible results produced. The sensitivity to different parameters can also be examined to understand which design inputs have the biggest impact on the required dyke sizing. By integrating the 3D TSF modelling tool Muk3D with GoldSim, it will be demonstrated how a wide range of scenarios can be evaluated and how that information can be used to make better decisions about the selection of design options.CITATION:Cooper, C A and Suter, G A, 2018. Starter dyke optimisation with Muk3D and GoldSim, in Proceedings Mine Waste and Tailings Stewardship Conference 2018, pp 466–475 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 23, 2018

Sampling protocols and metallurgical flow sheets should be designed to suit the style of mineralisation in question. In support, the a priori need for evaluation programs is the characterisation of the mineralisation type(s) and domain definition. The proportion and size of gold particles has a direct impact on the effectiveness of sampling protocols and metallurgical processes employed. Within the coarse- to-fi ne gold spectrum, the samplability of a deposit ranges from relatively simple for fine-grained disseminated particles, through to difficult for coarse gold mineralisation. Conversely, metallurgical processing may be relatively simple for coarse gold ore and more difficult for very fi ne gold ores. Most deposits contain a proportion of both particle size types. The nature of mineralisation, mineralogy and associated gold particle sizing can only be determined by preliminary sampling to facilitate testing. Mineralogical studies, focussing on ore mineralogy and gold particle deportment, size and distribution are required as part of wider paragenetic and geometallurgical investigations. This paper discusses key issues and presents a methodology for the determination of gold particle size in coarse gravity-gold ores to support sampling optimisation and which also contributes to metallurgical characterisation.

Aug 1, 2010

Continuous, steady-state laboratory flotation tests showed that the recovery of cha1copyrite from a naturally occurring ore, under conditions closely resembling those of plant practice, could be expressed in terms of a first order rate equation.Tests on full-scale plant flotation cells, using impulse tracers, indicated ideal mixing of the pulp in the cells.It was demonstrated that values of first order flotation rate constants can onlv be obtained from conventional methods of analysis in special cases.Analysis of a plant sampling campaign by the author supported a first order kinetic equation for two mineral species, and for the individual size fractions of one of these.The effect of stage-addition of reagents is interpreted in kinetic terms.

Jan 1, 1966

Longwall mining operations have been in place in Australia since the early 1960s. This mining method is currently used to extract the bulk of coal obtained from underground mines in Australia (CSIRO, 2010). Despite the high tonnages extracted the expected utilisation of much equipment remains relatively low. To some extent this level of utilisation is influenced by the variability in conditions inherent in the mining process. This variability in production rates presents challenges to those attempting to design a coal clearance system. The difficulty is to design a system that has sufficient capacity to support production, without over capitalising or incurring high operating costs. The need to allow for a series of largely unplanned events in the design of a coal clearance system makes simulation modelling an ideal technology to employ. Simulation modelling is a methodology that allows a system with interacting components to be modelled over time, while explicitly taking into account unplanned events that may disrupt operations.This paper discusses how dynamic simulation models have been used to assist in the design of coal clearance systems. Typically this type of modelling has been used to look at the likely profile of production rates from the Longwall shearer and to determine how well various proposed combinations of belts, bins and stockpiles would support production.

Sep 26, 2011

By G Deans, M Longbottom

OZ Minerals’ Carrapateena mine is one of Australia’s newest ‘greenfield’ mining deposits. It will be a 4.25 Mtpa sub level cave underground operation, with an estimated mine life of 20 years. The integration of stakeholder values to inform project development influenced the social and environmental outcomes. A Native Title Mining agreement was developed in 12 months. Project primary approval was obtained 12 months from submission, with achievable licence conditions and one public comment. The project moved from a Pre-feasibility Study in 2016 to construction in 2018. Following recent international dam failures, the Tailings Storage Facility (TSF) was a focus for Government approvals and stakeholder engagement. Significant effort was made into understanding the science around potential effects, impacts and risks. A leading practice Impact Assessment Framework that identified Sources, Pathways and Receptors was applied. A process of failure mode identification and layers of protection analysis was undertaken for robust design controls at each stage, while simultaneously transitioning between downstream and upstream discharge arrangements. Participatory selection of the TSF site and design layout was critical in managing project costs and environmental constraints, and in incorporating cultural heritage constraints and technical risks.

Jul 1, 2021

Silica and limestone fluxing levels in copper smelting slags were studied. Copper concentrates with flux additions were smelted to matte (55.5 per cent Cu) and slag in a pilot scale submerged combustion furnace.Results indicated that oxidic and sulphidic copper levels in slags were minimised with a slag Si02 level of 36 per cent and a SiO2/CaO ratio of 5.5. Total copper losses in slags were 0.6 per cent under these conditions.To produce the desired slag chemistry, additions of bulk silica and limestone to copper concentrates of fluctuating grades were predicted numerically. The method employed the solution of two simultaneous equations, each respectively for silica and limestone calculations.The predicted flux additions were applied in a further series of tests and the resultant stages were found to be satisfactory. The method is applicable to smelting 'operations which employ two flux bins, with weigh feeders, so that slag chemistry may be controlled with the flux/concentrate feed mix.

Jan 1, 1985