Search Documents

Confirmation that acid drainage (AD) was a significant environmental issue for the Australian minerals industry came in 1992 with the first national workshop on the topic. Subsequently the extent of AD was documented in a national survey published in 1997. The recommendations arising out of that survey served as a platform for actions by government, industry and industry-support organisations such as the Australian Centre for Mining Environmental Research (ACMER) to enable more effective prevention and management of AD. This paper briefly documents the extent of AD in the industry, the government regulations and guidelines for AD management, industry initiatives, the role of ACMER and other organisations in assisting industry through research and technology transfer, and the efforts being made to deal with AD at derelict mines. Future management of AD in the industry will be assisted by the linkage of Australia (through ACMER) into the International Network for Acid Prevention (INAP) which is facilitating the interchange of knowledge on AD as well as coordinating global research on the topic.

Jan 1, 2003

By R Coleman

The flotation mechanism plays a key role in the flotation process. It is used to provide the contact between solid particles and bubbles and also the energy for these particles and bubbles to attach. The mechanism must therefore provide sufficient mixing to keep the solids in suspension so that they can be transported into the froth and recovered to the concentrate. The design of the mechanism is critical and over the past decade Outotec has developed and optimised a new mechanism design to improve metallurgical and energy performance. The FloatForce® mechanism consists of a rotor and stator arrangement and has been specifically designed to provide sustained mixing at higher air flows and lower power inputs.Over 500 FloatForce® mechanisms have been installed in existing and new operations. This paper outlines the technological aspects of the FloatForce® mechanism and provides metallurgical, operational and energy performance results from a number of flotation circuits in which these have been installed.

Aug 8, 2011

The Australian coal industry has undergone sevenfold growth over the last 30 years and since 1985 has been the world's largest coal exporter. Three quarters of Australia's coal production is exported so its future is dependent on it remaining internationally competitive with other energy sources and other coal exporting countries. Coal is likely to increase its share of the energy market during the nine- ties as oil prices increase, new coal-fired capacity is commissioned and some form of nuclear energy is developed which is of acceptable safety standards to the community for use in the 21st century. Gas may take a part of coal's anticipated market share by the Year 2000. While coal exports will increase from China, Colombia, Indonesia and Venezuela and satisfy some of this additional coal demand Australia will also expand its export production, due to its existing advantages. The United States, Canada, South Africa, Poland and USSR seem unlikely to enjoy the same degrees of expansion and some, particularly Poland and USSR, will decline. Australia will always find it difficult to compete in the more distant markets due to levels of ocean freight, although its high quality coals will tend to partly offset such disadvantage.

Jan 1, 1988

By M Haydon

How do you portray a large structurally and stratigraphically complex deposit to return a meaningful resource estimation, and produce a geological model that is useable for planning on a daily basis? The George Fisher Mine is located 22 km north of Mount Isa and forms part of XstrataÆs Zinc Group operations. It is currently a major producer of zinc, lead and silver in the region with an estimated total resource for all categories of 127 Mt at 100g/t Ag, 5.3 per cent Pb and 9.2 per cent Zn (June 2005). Production in 2005 totalled 2 647 492 wet tonnes for 317 699 kg Ag, 140 317 tonnes Pb and 230 331 tonnes Zn from underground operations. George Fisher (GF) consists of two deposits that are structurally complex on a mine scale, George Fisher North (GFN) and George Fisher South (GFS). Regional faulting has resulted in a 2 km long package of variably pyritic shale and siltstone that separates the deposits. This paper looks specifically at GFN. Distinct correlations exist between the two deposits based on stratigraphic matches; however, orebody characteristics, geometry and fault architectures differ significantly between the two. The deposits consist of multiple, sedimentary-hosted, stratiform orebodies from 2 to 25 m wide, separated by waste intervals of variable width. Each ore-waste interval is modelled as an individual geological domain. Structurally, George Fisher North (GFN) contains a series of major late-stage NE faults with dextral offset(s) of up to 130 m. Further complexity is added by NS, NW and NNE striking fault orientations that can produce either a loss or repeat of stratigraphy, local drag folding, orebody attenuation and block rotation. Due to this structural complexity and orebody offsets, domains at GFN are further divided into fault blocks (FB). The GFN model comprises eight FBs over a strike length of 1 km, all of which are modelled independently. As drilling progresses and additional resources are converted, further FBs will be added at major fault offsets to accommodate orebody and model expansion. This will be in addition to what is already a large and time-consuming data set to manage and update. For example, each FB has 18 domains each with two constraining wireframes (hanging wall and footwall). Each wireframe has several sets of point data depending on the type of data available, ie diamond drilling, mapping or interpretation points. This equates to over 1100 separate files to manage. Additional wireframes and files are also required for major structures, daily planning requirements and block model runs. In total some 1500 files are managed, updated and maintained for GFN alone. The ongoing need to expand as a business and optimise production in the current economic climate where there is a global demand for metal has led to an increase in production at GF. This has resulted in a rapidly growing data set and highlights the importance of practical and efficient modelling to achieve a meaningful resource estimate. This paper focuses on the geological modelling, modelling approaches and techniques employed for the GFN deposit.

Jan 1, 2006

By Liu Wenyong, Huang Yucheng, Yang Ba

High-water rapid-solidifying material, called æhigh-water materialÆ, is a new material developed by the authors over many years. The material can solidify nine times its volume of water into solid. The material is a fine kind of binder with special properties. The solidifying body of high-water material with water has quite a high early strength. The compressive strength of the material within three days can reach the same strength as conventional Portland in 28 days. One ton of the material can replace three tons of conventional Portland cement as binder. Some important achievements have been made in application of high-water material. In metal mines, based on the material, a new full-tailing cemented backfill technology has been developed. The characteristic of the new technology is that high-water material is used as binder and full tailing or alluvial sand is used as backfill aggregate. Because of the application of the new technology, major technical problems in backfill technology such as classifying of tailing, dewatering, transportation of pulp, low strength of backfill body, environmental contamination and so on, have been solved.

Jan 1, 1998

By A B. Richards

A brick veneer house located on a open-pit coal mine lease has been subject to ground vibration levels of up to 222 mm/s, and air vibration levels of up to 145 dBL. The dynamic response of the structure was measured with accelerometers, geophones, and strain gauges as part of a project investigating the response of brick veneer houses to blasting. This paper outlines the project, and provides information on brickwork strength, foundation investigations, and observations on damage due to blasting. Correlations have been made between crack behaviour and factors such as blast vibration levels and rainfall.

Jan 1, 2001

By Selby J

South Australia's economic development has relied heavily on the mineral industry. In the late 1840s the rich copper deposits at Kapunda and Burra saved the Colony's economy when South Australia became a world copper producer. Copper lodes developed at Moonta-Wallaroo during the 1860s brought further prosperity when mining activities at Kapunda and Burra were in decline. In addition to those large mines there were many smaller workings scattered through the Flinders and Mount Lofty Ranges producing copper, gold, silver, lead and zinc. Most of the mines of this period were worked by Cornish immigrants who brought their own technology and mining methods with them. These people have left a cultural legacy unique in Aus- tralia. In this Jubilee 150 year (1986) the Department of Mines and Energy, working in conjunction with the Department of Environment and Planning, is helping to preserve and interpret selected historic mining sites, most of which have been neglected since their closure. This work is designed to draw people's interest to mining history by providing interpreted sites for them to visit and to demon- strate the importance of the mining industry in South Australia's cultural and economic develop- Ment.

Jan 1, 1987

By M J. Gillespie, P D. Erskine

Mine site rehabilitation generally includes the re-shaping of overburden to create a final landform, manipulation of substrates and subsequent revegetation. Due to the wide range of environmental variables that influence rehabilitation progression, having clearly-stated final land-use goals and ongoing significant contributions to the planning process, from prefeasibility through to mine closure, is essential for achieving stable landforms and sustainable rehabilitated communities. Two examples of rehabilitation processes in the phosphate rich region of North West Queensland are used to illustrate some of the possible benefits of early planning and communication of rehabilitation requirements.Approximately 160 km south of Mount Isa, Incitec Pivot Limited operates a 35 year old open cut mine at Phosphate Hill. Monitoring of rehabilitation areas and selected analogue sites is undertaken annually, but the initial landform design, substrate management and species selection has created a difficult environment for revegetated areas to successfully establish. Constant management input (such as weed management, erosion control, supplementary seeding, etc) will, therefore, be required over a long time frame.The second example uses exploratory drilling and historic costean pits at Legend International HoldingÆs Paradise South site, 135 km north of Mount Isa, to determine the success of natural vegetation colonisation on waste rock and compacted soils, and the effects of cattle grazing on recolonisation. This information can be used by planners of the mine life to inform possible end-land use decisions and proposed completion criteria.In a semi-arid environment such as North West Queensland, the creation of a post-mine landscape suitable for nature conservation and/or grazing can be an arduous task. The input from environmental personnel at all stages of the mining process will positively impact upon the quality of the resulting rehabilitation and ensure undesirable legacy issues are minimised.CITATION:Gillespie, M J and Erskine, P D, 2012. Importance of early rehabilitation planning - Case studies from North West Queensland, in Proceedings Life-of-Mine 2012 , pp 187-196 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 10, 2012

By R Sinclair, D Landwehr, I Hunter

"The Syama Gold Mine, located in southern Mali, was established in 1990 by Broken Hill Propriety Limited (BHP). The operation began treating oxide, and in 1994 it transitioned to processing hard and refractory ore based on ‘whole-of-ore’ roasting. In 1996, BHP was succeeded by Randgold Resources and the operation ran until 2001, when it was placed into care and maintenance.The Syama ore is classified as a double refractory ore with pyrite occluding the fine grained gold present in the ore and high levels of organic carbon presenting a challenge in terms of preg-robbing behaviour. The ore is extremely competent and this combination of metallurgical features was the main source of metallurgical problems encountered by the previous owners.Resolute Mining Limited (RML) acquired the Syama project in 2004. Following a feasibility study and the development of a revised processing flow sheet the plant was recommissioned in 2008 using a combination of old and new equipment. The revised flow sheet enabled primary sulfide ore to be treated by flotation and roasting of the concentrate to produce a calcine suitable for conventional carbon-in-leach (CIL) processing.Commissioning and ramp up of the plant was a troubled process, with monthly gold production being as low as 3000 oz in 2010. Poor availability of equipment and lower-than-forecast recoveries were the primary contributors.During the last five years, RML has utilised a systematic approach to improve production, focusing on mechanical reliability, metallurgical recovery and process bottlenecks. Modifications to the circuit have been as a result of both innovation and the application of technological improvements. Improvements have been made to the flotation, roasting and CIL circuits and RML has introduced a deslime circuit to treat flotation concentrate, in addition to the very successful commissioning of a new 1 Mt/a oxide circuit in December 2014. These changes have resulted in gold production increasing to more than 20 000 oz per month in 2015.This paper presents the processes, change implementation and outcomes of the modifications made to the sulfide circuit to address the availability and recovery problems.Apart from the expansion of an existing, world-class deposit and discovery of new resources, future improvements on the path to a class-leading gold mine include the continued reduction of the unit cash cost, increase in overall sulfide circuit gold recovery, increased throughput through continued innovation and consistency in the plant’s operation.Citation:Sinclair, R, Hunter, I and Landwehr, D, 2016. Syama Gold Mine - the Journey towards a Class-leading Gold Mine, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 213–224 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

WMC Limited, owner/operator of Olympic Dam, the worldÆs largest underground uranium mine and the fourth largest underground copper mine has now completed an expansion that has been classed as a benchmark in the mining industry. To achieve a production increase from 3.4 to 9.25 Mtpa from an underground mining operation in two years was a major challenge, it was essential to review the overall materials handling system from æthe face to the stockpileÆ. The challenge was two-fold:How to deliver 30 000 tonne of ore per day to the processing plant, from a single underground mine? To provide the processing plant with a consistent metallurgical feed. This paper traces the transformation from the old to the new materials handling system at Olympic Dam.

Jan 1, 2000

The offshore Maui gas/condensate field was discovered by Shell BP and Todd on Services Limited in 1969. Subsequent appraisal drilling and negotiations with the Government led to a development agreement, æThe Maui White Paper' being concluded in 1973. Part of this agreement provided for the Government to take a 50 per cent shareholding in the field. The field is comprised of a double domed anticlinal structure containing two gas reservoirs at depths ranging from 2700 - 3000 m. Water depth is 110 m. The development plan called for two standalone steel platforms to be installed sequentially over a period of some years depending on gas demand. The first platform (MPA) was put in place in 1976 but difficulties were experienced with piling and drilling of the 12 (later increased to 14) wells did not start until 1978. First gas was piped ashore late in 1979.

Jan 1, 1994

By D R. Wines

The design of near-surface civil infrastructure requires detailed consideration of the geological/ geotechnical conditions, excavation geometry and sequence and ground support measures to ensure stability of the underground openings and minimal impact on overlying or adjacent infrastructure. Twin parallel road tunnels have been designed and built with connecting cross passages and a piggyback busway tunnel as part of a large infrastructure project in Australia. The tunnels were excavated in poor to fair quality rocks using road headers. Temporary ground support includes shotcrete, rock bolts and canopy tubes. Extensive numerical analyses have been performed to analyse the expected behaviour of the tunnels during excavation, including two-dimensional analyses using UDEC and three-dimensional analyses using FLAC3D. Structural defects in the rock are explicitly included in the 2D analyses to examine the potential for localised ground instability. The stress redistribution is captured by the 3D modelling with an accurate representation of the complex excavation geometry and the detailed excavation and support sequence. This paper presents the modelling methodology, numerical results and discussions on integrating both 2D and 3D analyses to achieve reasonable design.

Mar 8, 2011

By S Hall

Mining schools around the world, many unfortunately now closed, were often established to teach the techniques of narrow vein mining and associated processing to students studying part-time while working in the industry. This arrangement ensured graduates (or æassociatesÆ) had a mix of skills and knowledge invaluable to the industry.It is argued that there is still a need to educate students in these narrow vein techniques and that there will be a growing demand for such graduates with a high level appreciation of this type of mining. There is also a need for innovation in narrow vein mining and processing to develop specific technologies and allow the use of techniques applied in æbulk miningÆ to achieve improvements in productivity, safety and economic performance.This paper aims to review the situation with regard to education and innovation in narrow vein mining.CITATION:Hall, S, 2012. Narrow vein education - back to the future?, in Proceedings Narrow Vein Mining 2012 , pp 23-26 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Mar 26, 2012

Many block caving operations experience difficulties during undercutting, resulting in draw horizon damage, production loss and extensive drift repairs for the life of the block cave. This paper deals specifically with block cave undercut aims strategies, methodologies and management to avoid the problems indicated above.

Jan 1, 2000

By P Klaric, N Swart, S Barnes

The recent advances in digital imaging technology, specifically around photogrammetry, have facilitated precision measurement in the difficult conditions encountered in an underground development mining environment. With the recent downturn in the resources industry, many mining houses have begun to focus on cost reduction projects and driving efficiencies. The application of digital photogrammetry has allowed greater insight into the development mining cycle and supported a focus on areas where efficiencies and cost savings can be achieved. Data collation, via digital image capture, can be completed with minimal disruption to the development mining cycle with analyses taking a nominal time to process and interpret. The result can be a stark visual representation of the result of blasting and associated activities of the development mining cycle. Many millions of dollars of benefit can be derived from understanding the impact of each component of the development mining process, with some of the biggest savings associated with conformance to drill design and the minimisation of overbreak during blasting. This paper will explain the image capture process, analyses and instigated improvement opportunities that were undertaken at a number of mine sites to improve efficiencies and drive savings in their development mining processes.CITATION:Klaric, P, Swart, N and Barnes, S, 2017. Digital imaging provides valuable insights into underground development mining, in Proceedings 13th AusIMM Underground Operators’ Conference 2017, pp 129–134 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 16, 2017

By A B. Bayooke, A C. Robertson

In terms of underground tunnelling in metres advance per capita, Australasia compares well with the best world performers. This is because of the large number of metalliferous mines, coalmines and civil tunnelling projects, with the Australian tunnel advance for civil and mining projects exceeding 625?km/a. In terms of hard rock quarry extraction, Australia produces approximately 200?Mt/a of aggregates, roadbase, fill material and specialist rock products from its quarries, which equates to approximately 8?t/capita. Australian mining and tunnelling contractors are also of world standard and are used to excavating in a variable range of ground conditions in a competitive environment. One author has been involved in tunnel and underground space planning and quarrying in Australia for the past 25 years and predicts that, over the next 20 years, there will be a major swing towards underground space for commercial uses. This paper identifies the potential uses of underground commercial excavation and the planning and geotechnical challenges for the future. Underground quarrying creates new opportunities to extend existing quarries within their urban footprint with minimum impact on the surrounding community. Investigations by the authors reveal that there are very few cities in the world that actually incorporate underground space planning in their city plans. However, cities such as Helsinki have been planned in detail to utilise the rock resources beneath them. Brisbane is used as a case study for a practical application of commercial underground space and underground quarrying in Australia.CITATION:Bayooke, A B and Robertson, A C, 2014. Geotechnical challenges for underground commercial space and quarrying in Australia, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 317–322 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014

By H Allday

The mining industry’s attention has shifted over the last decade with the recovery from the downturn resulting in greater development of innovation and new work methods in a bid to remain competitive and deliver higher productivity. The emphasis on cost reduction to improve profit margins has primarily been the focus of the “work smarter” campaigns embraced within the industry. But is this strategy holistically the best-for-business, or does it place a ceiling on revenue opportunities and inhibit mining companies from truly maximising value? Businesses need to maintain a balance between active cost management and revenue generation often resulting in cost reduction strategies at site level. These strategies have merit, assessing areas of cost wastage across operations and creating space for opportunity. However, this potentially can create distractions from the goal of enabling growth and lead to the sacrifice of quality and delivery. Focusing too heavily on cost reductions without addressing revenue generation is an unprofitable lens to look through, and the relationships between cost, revenue, quality and profit margin can often be overlooked resulting in missed opportunity to maximise value. How these relationships are effectively employed by mining companies to reap the rewards from an overarching corporate perspective down to site level remains a fluid concept depending on the nature, operating market and strategy of the business. A common directive from businesses to their operations is to strive for greater profitability and productivity. The quantification of these requirements, and the nature of the cascading message delivered, impacts the methods employed by the operational team to meet the expectations of the business. Cascaded strategies, if not delivered with appropriate participation and buy-in can often be perceived to be knee-jerk and create frustration for operations who are squeezed to deliver on expectations by slashing site costs. This squeezing is not only felt by the mining operation but at the individual level and can result in increased team stresses. In some cases, this may also steer behaviours towards activities that result in corner cutting and an elevation of operational risk, potentially increasing associated incidents and injury. Driving down costs by any means can create an unhealthy tunnel vision where value is no-longer assessed for best-forbusiness results. By flipping the viewpoint to a value-based approach revenue opportunity may be realised and potentially exceeded, however this opportunity may be missed if value is over shadowed by a cost heavy focus. By analysing a selection of real operational cases (ranging from mining contractors through to in-house mining giants), it becomes apparent that practical revenue maximisation strategies are not only key to an increase in value and cash flow but to a stronger understanding of business drivers for sites and operators alike. In the cases evaluated additional revenue opportunities are foregone in favour of cost reduction strategies resulting in negative impacts on the associated operations and wider businesses. Alignment towards value generation is king. If strategies are not implemented focusing towards value and revenue maximisation, the opportunity loss experienced by mining operations could continue be great and the question should be posed; when the next up-turn hits will operations be ready to reap the rewards or still have a glass ceiling above their heads?

Mar 15, 2021

By D J. Brake

The risk from fire remains one of the most serious of underground mine disaster scenarios. The impacts of mine fires on the underground ventilation system and the production of toxic gases have been difficult to model and therefore assessments have relied largely on empirical data, historical precedent and subjective opinions. Underground fire modelling software has had limited availability and been technically challenging and time consuming to use especially for routine mine investigations. There has also been no well-accepted set of assumptions for fire modelling in mines, which has resulted in a lack of confidence in adopting its use more widely. This paper describes modelling of three critical fire scenarios in underground hard rock mines: a fire (LHD) in an underground diesel refuelling facility, a fire in an underground explosives magazine and a fire on an underground ore transport conveyor. Modelling was undertaken using VentsimÆs VentFIREÖ fire simulation module. It describes the basis of design, the key assumptions, the methodology used and provides examples of the outputs, conclusions and recommendations. It reviews the impacts of these fires on egress and entrapment strategies in the mine. Some general principles regarding improvements to ventilation circuit design based on this analysis are also recommended. Whilst the fire scenarios were based on actual case studies, they have been disguised for this paper.CITATION:Brake, D J, 2013. Fire modelling in underground mines using Ventsim Visual VentFIRE software, in Proceedings The Australian Mine Ventilation Conference , pp 265-276 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 1, 2013

By S J. Schafrik, Z Agioutantis, E C. Jong, K Luxbacher

Real-time monitoring of mine operating parameters is available at most mines. However, access to these data for an individual operation is typically underutilised by mine managers and technical personnel. Such monitoring systems are typically designed to provide data streams and alarms to a responsible person, but they are not utilised to extract underlying trends or correlate different data groups. Furthermore, multiple monitoring systems are usually implemented at a given site without interconnection between vendors’ systems or connection to any central management, and mine personnel are only exposed to a minimal subset of such data. Thus, it is not easy to analyse and correlate individual data streams and generate information to enhance day-to-day operational decision-making and improve safety and efficiency.This paper addresses the primary challenges associated with centralising data management and effecting greater utilisation of the vast amount of collected data, while at the same time reducing the time and effort required to manage such large data sets. Furthermore, it presents the conceptual design of a database application that can organise, present and analyse data collected by multiple sensors in different environments. The database is designed to operate in a passive manner so that active mine data management systems are not impacted. An example is given where this database is used for managing atmospheric data collected at an underground coalmine operation in the US. These techniques have a universal application and can be incorporated in a wide range of mining and construction projects.CITATION:Agioutantis, Z, Schafrik, S J, Jong, E C, Luxbacher, K and Karmis, M, 2015. A platform for managing and analysing atmospheric data in underground coalmines, in Proceedings Third International Future Mining Conference, pp 3–10 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 4, 2015

By M Warnken

Major cities are not only the focal point for AustralianÆs work, leisure and homes, they also are the focal point for the flow of resources into the built environment, motor cars and transportation and urban consumables. The steady increases in æstockÆ and waste generation, in line with GDP growth, means that cities will become the mine sites of the future if the inherent value is recovered from these materials at end of life. The urban waste stream can be characterised as containing approximately nine per cent hydrocarbon-based materials; 57 per cent biomass-based material; 28 per cent fully mineralised materials that are inert, five per cent metals and less than one per cent of problematic materials that are potentially hazardous and toxic. In order to convert these wastes into value added inputs into the economy, a number of technological interventions are required. These æurban waste mining techniquesÆ revolve around source separation and material streaming. One issue that needs to be overcome when determining which mining technique to implement, is identifying the option that will deliver optimal value, both from a financial and a sustainability perspective. The difference between embodied energy and calorific value is a case in point. Highest net resource value (HNRV) is a concept that can assist in choosing between different resource recovery options. The assessment can be done at a strategic level, or can be used to work out material specific issues. For example, used tyres can be recovered for their energy content at an approximate cost of $120 per tonne, whereas mechanical processing of used tyres can deliver a net benefit of $192.

Jan 1, 2006