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By A T. Bernardes

Using the cellular automata computational technique it was possible to simulate the generation and discharge of an iron ore pellet pile inside a direct iron reduction oven, as well as to calculate the reduction degree of the pellets as they leave the oven. It allows simulation of the variation of operational parameters and verify the results of those variations in the pellet reduction degree. The simulated data was validated in two instances: for the dynamics of the pellet flow inside the oven it was used in an acrylic bi-dimensional silo; and data from direct reduction iron literature was used for validation of the pellet reduction. The simulated results were considered acceptable to describe the movement of the iron pellet inside the direct reduction iron oven and to describe the iron pellet reduction direct in the oven.

Sep 26, 2011

Coal mining in the Illawarra commenced in 1848. By the early twentieth century mining operations were spread over quite a distance along the coast centred on Wollongong. By this time there were already numerous tunnel mines and one shaft mine. Coal was first reported in Illawarra by Lieutenant Flinders on a voyage of exploration, southerly along the coast from Sydney in 1796. Because of the topography, particularly the escarpment and the narrowness of the coastal plain, access from Sydney was not easy by land and the normal access was by sea. It was not until some coastal areas had been developed for agricultural purposes that the mining of the seams on the South Coast commenced for the supp- ly of fuel. The most important mines in the early nineteenth century were Bulli and Osborne Wallsend. In general, coal was won from the tunnel mines and was transported directly, usually by tramway, to the nearest shipping point. Considerable hardship attended the earliest attempts at mining coal in regard to materials for mining and the way of life of the miners in the vicinity of the mines. With the growth of production and the installation of coke ovens at some mines the area, hitherto virgin bush- land, began to take on a more industrialised appearance. The mines were necessarily small,

Jan 1, 1976

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 K Tanguturi, B Belle, R Balusu

Management of high rates of goaf gas emissions between 4000 and 6000 L/s of methane gas in longwall panels is a challenging issue, particularly in start-up areas of the panels. There is a need for investigation of the effect of various goaf gas drainage concepts and techniques, and development of effective gas drainage strategies for management of high goaf gas emissions in start-up areas of the longwall panels. This paper presents the results of various computational fluid dynamics (CFD) simulations that were carried out to investigate the effect of different goaf gas drainage strategies and combinations for gas management in the start-up area of the longwall panels. Results indicated that the gas (methane) concentration in goaf holes on the tailgate (TG) side vary between 50 and 75 per cent under the simulated field conditions with flat coal seam gradients. The results also indicated that operation of more goaf holes for draining the goaf gas on the TG side results in high ingress of oxygen and further reduction in gas concentration in goaf gas drainage holes. The simulations also included scenarios with goaf gas drainage holes on the maingate (MG) side, TG cut-through seal and near the start-up area. This paper presents the results of various goaf gas drainage strategies and discusses the effect of various combinations in order to develop effective goaf gas drainage strategies for gas management in start-up areas of the longwall panels.CITATION:Tanguturi, K, Balusu, R and Belle, B, 2015. Development of goaf gas drainage strategies for start-up areas of highly gassy longwall panels, in Proceedings The Australian Mine Ventilation Conference, pp 251–258 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 31, 2015

By J Wu

Swirl Flow Technology (SFT), a novel approach for agitation in large industrial slurry tanks, was jointly developed and patented by CSIRO and Queensland Alumina Ltd (QAL). Currently, SFT is used in 16 alumina precipitation tanks at QAL, with the first installation in January 1997. This paper provides insight to the underlying fluid dynamics, which were investigated through pilot-scale experiments. A key finding was that SFT produces tank wall velocities approximately four times that of conventional draft tube agitator systems for the same power input, whilst for solids suspension, much less power is needed. SFT is energy efficient and practical in scaling suppression as demonstrated by the full-scale experience at QAL.

Aug 8, 2011

By O Aydan, R Ulusay

Blasting is the most commonly used excavation technique in mining and civil engineering applications. Blasting induces strong ground motions and fracturing of rock mass in rock excavations. Particularly, high ground motions may also induce some instability problems of rock mass and structures nearby. Furthermore, it may cause some environmental problems due to noise as well as vibrations of structures near the populated areas. Furthermore, flyrocks is another major issue for the safety of people and damage to machinery and equipments when blasting is employed. In this study, the authors explore the ways how to estimate the ground motions as a function of distance, amount of explosive, number of holes. The ground motions were measured by stand-alone accelerometers developed by the first author and some empirical relations are developed. The effect of ground motions on the instability issues of benches such as sliding, toppling and rockfalls were investigated. Furthermore, the flyrock issue is investigated and some empirical relations to estimate the maximum distance of flyrocks from the blasting relations are compared and discussed. CITATION:Aydan, O and Ulusay, R, 2018. The ground motions induced by blasting in open pit lignite mines and its environmental effects, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), pp 142–151 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

The Gj0vik Olympic Mountain Hall is the world's largest underground cavern for public use and was created primarily to facilitate the ice hockey tournaments for the 1994 winter Olympics in Norway. The cavern has a span of 61 m, is 91 m long and is 25 m high. Ordinarily, rock caverns have a span width of 15 to 25 m, however, temporary mining caverns of up to 60 m have been excavated and natural caves with even greater dimensions occur. The Gj0vik Olympic Mountain Hall is unique as it is for public use with a capacity for 5800 spectators. Blasting was conducted with a high production rate at normal costs due to detailed planning and strict supervision of each round. The initiation system and vibration monitors were the main tools to control vibration levels and to facilitate a high production rate. It was of utmost importance that the rock remaining in the roofs and walls was of high quality after blasting to avoid rock fall, rock slides and excessive maintenance work.

Jan 1, 1995

By Gray E, Banks J

In mine site revegetation, exotic grasses are more commonly used than native grasses. This is due to unavailability of native grass seed on a commerical scale and lack of information on agronomical aspects of native grasses. This paper lists a number of native grass species that have the potential to grow well on mine sites, and provides some information on their seed collection, processing and germination. Further, it demonstrates via results of a field trial conducted at Ranger Mine spoil the relative performance of ten native grasses and Rhodes grass. It is concluded that (i) some native grasses have similar ability to grow on mine spoils compared to Rhodes grass and (ii) the use of native grasses have added advantages in ecosystem restoration.

Jan 1, 1994

By R Berry, J Lett, C L. Harraden

"In the past decade, increased processing capacity combined with precision robotics in high resolution spectrometers has resulted in a new generation of high-speed hyperspectral core logging systems. The application of these multisensor automated platforms provides a key advancement in the characterisation of metal resources. The development of this technology has allowed for comprehensive, drill core-based, mine-scale rock mass characterisation studies. Here we propose a new method for the extraction of parameters that seek to more accurately quantify ground conditions, including quantified rock mass rating (RMR) and the Rock Tunnelling Quality (Q) Index. Data inputs include rock quality designation (RQD), number of joint sets, joint roughness, joint alteration and joint spacing. Geologists and geotechnical engineers have historically collected these inputs by manually logging drill core. With automated core scanning technologies, these parameters can be estimated from the acquired image data and used to objectively calculate RMR and Q-index values for oriented core.Corescan is an automated hyperspectral core scanner that uses a 3D laser profiling system to measure the height of the surface of drill core. This technology allows for rapid core analysis to produce detailed fracture and rock condition data. Through an integrated geometallurgical approach, the proposed methodology will test the accuracy of joint measurement using the height profile Corescan data from oriented drill core. This will be combined with joint roughness and alteration mineralogy measured from the hyperspectral images to calculate the RMR and the Q-index continuously downhole. The values obtained can then be compared to the traditional, manual geotechnical log data. If the precision is sufficient, these techniques can then be applied site-wide to automate the collection and modelling of key ground condition classification indices across an entire deposit. Compared to the laborious manual geotechnical logging procedures that currently form the industry standard, utilisation of core laser profile data and high resolution red-green-blue (RGB) images provide an opportunity to collect large volumes of consistent geotechnical data, which can increase the efficiency and accuracy of deposit scale geotechnical models.CITATION:Harraden, C L, Berry, R and Lett, J, 2016. Proposed Methodology for Utilising Automated Core Logging Technology to Extract Geotechnical Index Parameters, in Proceedings The Third AusIMM International Geometallurgy Conference (GeoMet) 2016, pp 119–124 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jun 15, 2016

Equilibrium in the reaction H2(g) + [%0] (in liquid copper) = H2O (g) was investigated at temperatures between 1200 -and 1350°C with p(H2Oj/p(H2) ratios between 1 to 15. A semi-microbalance was used for direct measurement of dissolved oxygen in molten copper. Oxygen was found to obey Henry's law under the experimental conditions used. The standard free-energy change for the above reaction is given by Equation 1where 1 weight per cent solution is the standard state for dissolved oxygen.For the dissolution of oxygen in copper according to 1/2 O2(g) = [%0] (liq. Cu), the standard free energychange is given byEquation 2.

Jan 1, 1973

By R Dunne, W McCallum

Continuous improvement might be defined as seeking incremental improvement over time through improved equipment, processes, technology and the efforts of people. Most people working in ore processing facilities embrace the general principles of continuous improvement. However, given the industry-wide issues with skilled personnel and the constantly changing environment in ore processing facilities, it is often difficult to identify improvements in a facility over a given time period. The driver for these outcomes is the use of basic principles and technology to achieve best practice targets. The process involves four stages: develop standards of practice to define best practice in specific areas; write procedures to guide the organisation towards these best practices; implement the procedures and develop a review process to provide a method of measuring performance against best practice.By reviewing performance against best practice on a regular basis, the organisation measures progress towards the best practice targets and the incremental improvement between these regular reviews is a measure of continuous improvement.This paper provides the background for developing standards of practice for metal accounting, metallurgy and metallurgical management. The paper also describes how standards of practice can be used to develop continuous improvement and the skills set of the departmentÆs leadership team.CITATION:McCallum, W and Dunne, R, 2012. Metallurgical management tools for continuous improvement, in Proceedings 11th AusIMM Mill OperatorsÆ Conference, pp 225-230 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 29, 2012

By B Ellis

Brunswick Mine is one of the largest underground zinc/lead mines in Canada, producing 3.4 million tones of ore annually. As mining activities advance to deeper levels, ground pressure also becomes greater. To cope with the highly stressed ground, the mine has taken some strategic measures to ensure the targeted production level. Such measures include the implementation of a pastefill system and transferring the mining method from primary/secondary stoping to pillarless pyramid stoping. With the pillarless mining method, stope sizes become smaller and the number of active stopes is also less than before. In addition, mining sequence and cycle time have to be strictly followed according to production schedule. The blasting project described in this paper tackles one of the steps in the mining cycle aimed at shortening the blasting cycle time in a stope. Furthermore, this project was conducted and managed with the Six Sigma initiative in Noranda which was implemented in the fall of 1999. Like a typical process review, the blasting operation was examined by breaking it down into many steps that can be quantified and measured. Each activity was then correlated with different factors associated with blast design as well as blast operations underground. It was found that the utilisation of voids plays a key role in the blasting cycle time. With improved void utilisation ratio, blasting cycle time has been reduced from an average of 12 shifts to ten shifts per stope. This improvement translates into approximately 180 000 tonnes of ore being blasted without any increase in manpower. This paper presents the technical aspects of the study, as well as some operational issues and improvements made during the project.

Jan 1, 2001

It would be a good thing when reviewing the challenges to be faced by the Australian gold industry to set the backdrop and scene for them, by briefly examining the history of this vital and dynamic industry in the Australian context. Gold mining in Australia had its official beginnings in 1851 when John Lister and William Tom discovered gold at YorkyÆs Corner, later renamed Ophir by Edward Hargraves. From that first tentative beginning, the ensuing rush of prospectors into New South Wales and Victoria meant that the annual gold production in those early years surpassed that of the next 40 years. This early rate of production was only eclipsed when AustraliaÆs production was once again lifted by the discovery of gold on the other side of the continent, in Western Australia. (Figure 1). The years leading up to the First World War saw Australian production peaking once again at over 115 tonnes of gold, a production rate that would not be surpassed until 1988. This renaissance in production at the beginning of the 1980s was achieved by the application of technology. The advent of bigger trucks and shovels meant that earth-moving costs dropped dramatically. This, coupled with the highly effective and efficient carbon-in-pulp processing route, stimulated the Australian gold mining industry into a state of frenetic activity. These two innovations were the principal factors that enabled the economic exploitation of the lower grade haloes left by the æold-timersÆ around the deposits exploited at the beginning of the last century-no high finding costs here. AustraliaÆs production through the 1980s and the early part of the 1990s was largely supported by the exploitation of these haloes. As these were depleted, the aggressive exploration effort stimulated by the strong cashflows of these early oxide deposits resulted in new æblindÆ discoveries which are now emerging as the backbone of the Australian industry (Figure 2). Gold production is a major contributor to the Australian economy. In 1998/99 the Australian gold industry accounted for approximately 16 per cent of the value of all mineral exports, which in turn accounted for over 35 per cent of AustraliaÆs total exports. As such, the Australian gold industry, by itself, accounts for just under six per cent of AustraliaÆs total exports (Figure 3). Consequently, the industry is responsible for over one per cent of AustraliaÆs gross domestic product. These statistics are all the more compelling when we consider that, at the beginning of the 1980s, goldÆs contribution to exports and GDP was insignificant (Figure 4). Within the Australian resources industry, gold mines and associated infrastructure account for ten per cent of all capital expenditure (Figure 5). From an employment point of view, in 1997/1998 the industry directly employed (excluding contractors) about 7700 people, approximately 15 per cent of all those employed in the minerals industry. Just under nine per cent of the workforce in the minerals industry are female, whereas in the gold industry over 16 per cent are female.

Jan 1, 2000

By D Van Doorselaere

The purpose of blasting during mining is to produce a muck pile that can be efficiently loaded and transported. There is an increasing awareness of the variation in muck pile characteristics and its economic implications. It is well known that good fragmentation by itself is not sufficient to optimise the muck loading efficiency. The swelling and configuration of the muck pile also significantly affect the productivity of the loading equipment. The characteristics of a muck pile depend upon the blast design parameters, explosive properties and rock mass geology. This study has focused on the dependence of muck pile configuration on blast design parameters, explosive properties and size distribution of the muck.The field work was done in two phases. In the first phase 12 blasts were monitored, while in the second, three blasts were monitored. The blast design parameters and explosive properties for each blast were documented and the following muck pile characteristics were measured:muck pile height and its distance from the facedistance of throwwidth of the power troughsize distribution by image analysis technique.The effects of burden, bench height, heave energy of explosive, row-to-row delay, powder factor and the mean particle size of the fragments on muck pile configuration were examined. It was observed that muck pile height and distance of throw are strongly influenced by the burden, bench height, heave energy of the explosive and the size distribution of the muck. The width of the power trough depends upon the row-to-row delay, powder factor and total burden. In addition, the effect of the fragment size distribution on the muck pile parameters has also been discussed.CITATION:Singh, S P and Van Doorselaere, D, 2015. The relationship between blasting parameters and muck pile configuration, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 369–374 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By K Mayank, A N. Mainza, I Govender, M Narasimha, A Mittal

In mineral processing industries grinding is the most energy-consuming process. A tumbling mill is an essential grinding equipment widely used for particle size reduction. Power consumption, impact forces and trajectory paths are critical parameters for characterising a tumbling mill to determine grinding efficiency. The effect of lifters and mill speed plays a vital role in such parameters. However, most of the studies ignore the impact of the lifter and do not investigate the effect of slurry dynamics on charge motion. The focus of the present work is to prepare a computational model that can accurately predict the complex multi-phase dynamics of charge particles, air and slurry inside the mill using a model that couples computational fluid dynamics (CFD) and the discrete element method (DEM). The details of impact forces with lifter profiles and mill speed variations will be refined even further using the CFD-DEM coupling approach. The slurry-air free surface is modelled using the volume of fluid (VOF) method, and the charge motion is modelled using the DEM. The phases are coupled using the interface momentum exchange between the charge and the fluid slurry. The coupled model is validated against experimental results from the positron-emitting particle tracking (PEPT) data. The validated model compares the effect of slurry content on charge dynamics with the dry DEM model. The presence of slurry is observed to dampen the tangential and shear contact forces.

Aug 24, 2022

By Y T. J Kwong

With the recent emphasis worldwide on environmental protection and sustainable development, finding an enriched mineral deposit no longer guarantees mining development. Only if the identified resource can be exploited in an environmentally-friendly manner is it possible that a mine may be developed. Designed primarily to aid with exploring for similar deposits of a particular type, traditional genetic ore deposit models tend to ignore the fact that all mineral deposits are characterised by type-specific environmental signatures. In fact, how an ore deposit can be mined, the commodities of interest extracted and the resultant mine wastes managed are all largely dictated by the geology and mineralogy as well as the environmental setting of the deposit. An environmental ore deposit model integrates such related information to identify the environmental challenges associated with mining an ore deposit of a particular type and facilitates the selection a suitable combination of methods to minimise environmental risks and impacts. Given that environmental management consumes a large portion of the budget for a modern mining project, making informed decisions at all stages of mining development can reduce the overall project cost. Through case examples, this paper demonstrates how environmental ore deposit models may be useful in mine permitting, active mining and in site decommissioning. It is only through an innovative and flexible approach that the mining industry can shed its tarnished image and gain the social license to mine.

Aug 22, 2011

By Noller B. N, Mine F. J

Modem open cut and underground mining in the tropics inevitably expose partially weathered and unweathered rocks to oxygen and water, leading to weathering and the release of solutes and often acidity as well. Historical monitoring data can demonstrate these phenomena. Three case studies from open cut mines in the north of the Northern Territory illustrate the deterioration in quality of pond water receiving drainage from waste rock dumps. The potential for deterioration of water quality was not recognised in many mine Environmental Impact Statements prepared and accepted in the 1980s. The examples documented indicate the importance of adequately planning for this near inevitable process. Retrofitting a mine water management system to 'no' or minimal release can be very difficult and expensive, and may not be feasible, leading to downstream pollution. The characterisation of acid and solute production potential of ore and waste rock, and improved dumping strategies and water management are very important to minimise the environmental impact of mining in the tropics.

Jan 1, 1994

For Australian mining projects, sustainable groundwater use is typically defined as a groundwater extraction regime, measured over a specified planning time frame, which allows acceptable levels of stress and protects dependent economic, social and environmental values (DEH, 2004). This principle is compatible with most stakeholdersÆ understanding of our national environmental objectives, yet the application of this policy on a project-specific scale is not always straightforward. Three examples of sustainability issues in the management of groundwater in mining are presented. These examples highlight each of the three dependent values: environmental, economic and social.

Jan 1, 2006

By K Sommerville, J Parkinson

"Open pit mines today have more technology and data available. The challenge is to effectively use resources to analyse and identify mine productivity improvements. AMC Consultants Pty Ltd (AMC) has completed more than 100 benchmarking studies worldwide. In the process of gathering cost and productivity data, insights have been gained on how mines are using data to drive productivity. This paper aims to share good practice on using data, what benchmarks operations should be aiming for, where mines are currently sitting, high value areas to target, and how to best prioritise improvement to meet operational goals.A key purpose of data is to assist in managing and improving operations. Key information is used to drive meetings, decisions, budget estimates and reports. Safety, equipment productivity, available stocks, grade and spatial reconciliation are examples of where data is important for management systems. The key is to keep reporting simple whilst maintaining access to source data for troubleshooting and analysis.Some operations still have paper-based reporting systems. Some operations collect data directly off machines and instruments, use cameras and have off-site control centres. The level of technology is a fit-for-purpose choice.Comparisons of productivity assumptions commonly used in feasibility studies with good practice productivity numbers sourced from AMC’s benchmarking database will be shared in this paper. A typical activity mining cost breakdown will highlight where the high value areas for productivity improvement sit.In addition to examining the productivity of each mining step it is also important to examine the impact on the mine plan. Equipment numbers, strip ratio, grade and material hardness can impact the results of bottleneck analysis. A bottleneck example case study will highlight how productivity and other factors can be used to identify and prioritise improvement opportunities.Keep it simple. Use only the critical data for meetings, decision-making, reports and plans. Knowing and communicating the key performance indicators (KPIs) you are striving for aligns the operation and prioritises improvement plans.Citation:Parkinson, J and Sommerville, K, 2016. Getting the Most Out of Technology to Drive Mine Productivity Improvements, in Proceedings Ninth AusIMM Open Pit Operators' Conference 2016, pp 84–93 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 15, 2016

By V S. Mutton, M J. Shearer

"The current economic challenges faced by the mining industry led to a review of options for reducing the cost of ventilation control devices (VCDs). The VCDs at the Mount Isa Mines site operated by Glencore in Queensland typically experienced significant damage on the operating levels and required expensive replacements. Ventilation controls can become damaged by the effects of stope firings. This paper discusses the nature of blast wave effects, giving consideration to distance from the firing and changes in mine geometry. The time taken to adjust the airflow on the operating levels with the current VCDs resulted in the loss of productivity opportunities. The mine site engaged an equipment supplier to collaborate on the development of a high-strength regulator to control the required airflows within its underground workings.The strengthened regulator proved to be cost-effective and provided additional benefits, including ease of use, simplicity of installation and speed of change in the control of available ventilating airflow. An added advantage of the re-engineered regulator compared to contemporary VCDs is its flexibility, which includes the ability to easily move mobile equipment into different ventilation districts where required without the need to remove the VCD from its location. This paper describes both the innovation and environmental sustainability approaches followed when developing the new regulator for its implementation at the site.CITATION:Shearer, M J and Mutton, V S, 2015. Advanced ventilation control – an analysis of innovation and environmental sustainability, in Proceedings The Australian Mine Ventilation Conference, pp 55–62 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Aug 31, 2015