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By B Besa, E K. Chanda

It has long been recognised that narrow vein mining needs innovative approaches to mine access and mining methods in order to improve the economics of this vital part of the mining industry. The mining equipment used currently requires large openings in narrow vein-type deposits making mining operations uneconomical. In view of this and other shortcomings of the current mining practices, a study was initiated to investigate the potential of using low profile electric loader with mounted conveyor in conjunction with the electric monorail haulage system (EMTS) to load and haul the blasted material, particularly in decline development and main haulages. Computer simulation based on the General Purpose Simulation System/Henrikson (GPSS/H) is used to model the system and evaluate its performance. The results are compared with those for conventional mining using trucks and loaders. The EMTS provides competitive haulage rates in substantially smaller excavations than is currently achievable. According to simulation results, the electric loader in conjunction with the EMTS had the same number of blasts as the conventional system and hence the same advance rate of 3.33 m per 12 hour shift. Furthermore, the total drill-blast-load-haul cycle time was less than the conventional system by one hour.CITATION:Besa, B and Chanda, E K, 2012. Evaluation of low profile electric loader in conjunction with electric monorail haulage system in narrow vein mining, in Proceedings Narrow Vein Mining 2012 , pp 221-228 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Mar 26, 2012

The screening of iron ores, sinter and coke, and investigations undertaken to improve screening efficiency and cloth life are discussed. The major modifications to coke screening proposed with the construction of No. 7 coke ovens battery are briefly described. The major problem areas were identified as screen cloth blinding and pegging, feed presentation and screen overloading. Blinding and pegging have had a significant effect upon screening efficiency with the screening of sinter, coke breeze and wet iron ores in particular. Pegging can be reduced or eliminated by the correct selection of aperture size and shape, screen excitation and slope, and screening medium. Blinding encountered with wet coke breeze was a particular problem in which no significant progress was made.

Jan 1, 1984

By de Bruin J H

A method new to Australia was used for sinking a vertical shaft at Broken Hill in the development of Pasminco Southern Operations No 5 Ventilation Shaft. The 6 m diameter shaft of 820 m depth was planned with a construction method which allowed access for ground support as sinking proceeded by mechanical excavation.The vertical shaft boring machine, known as the V-Mole, was originally developed in West Germany. The machine operates in a manner similar to a full face TBM but vertically and the cuttings drop down a previously constructed raise. The raise is subject to stringent tolerance on verticality and must remain stable for the duration of reaming.

Jan 1, 1993

By K Ellis, B Lumsden

A full-scale statistically-based on/off plant trial of a new flotation conditioning technology designed to improve fine mineral recovery was undertaken to determine whether the recovery of selected fine sulfide minerals can be increased. The technology is selective for certain sulfide minerals only, including chalcopyrite and sphalerite. The technology has been shown to selectively aggregate the fine chalcopyrite and sphalerite minerals giving increased flotation recovery. The plant trials have shown an increase in the mineral recovery, without decreasing selectivity. Size by size recovery shows a significant increase in the fine (

Jan 1, 2005

By Brumley J

The development of the SECV brown coal open cut at Loy Yang will require depressurisation of aquifers both within and below the coal seam sequence in order to maintain open cut stability. Prediction of future open cut dewatering requirements at Loy Yang Open Cut and evaluation of the regional consequences of dewatering has required development of a detailed hydrogeological model of the Loy Yang area. The complex stratigraphy of the coal seam and aquifer/aquitard sequences at Loy Yang have been analysed and integrated with the hydrogeological concepts developed from regional groundwater studies to formulate a realistic hydrogeological model as a basis for finite-element flow modelling.

Jan 1, 1988

By F P. van der Meer, E Lessing, E Matthies

High pressure grinding rolls (HPGR) technology is growing to be a common comminution tool in iron ore processing. The technology finds a wide acceptance and presents specific benefits in coarse ore grinding and closed-circuit grinding in preparation of ball mill feed, right down to the other end of the particle size spectrum for iron ore pellet feed preparation.A growing number of minerals processing plants are facing higher operating costs and difficulties due to a scarcity of process water, which in some cases is a result of more stringent environmental constraints. In addition, many new iron ore deposits are located in more arid regions of the world. These challenges have led to operators taking a new look at dry processing of iron ores.The use of dry crushing and classification technology in cement production from blast furnace slag, clinker material or limestone feed stocks indicates that the technology may be applied in minerals processing. In addition, dry processing provides the possibility of generating a final product from finely disseminated and inter-grown ores at sizes near or well below 100 µm, as may be required for beneficiation techniques such as in fine magnetic separation, flotation or magnetic flocculation.Dry grinding by HPGR has a number of specific features, challenges and opportunities, including balancing power input, moisture content requirements and classification efficiency in the process design. HPGR parameters and the latest HPGR design and sizing capabilities indicate considerable potential benefits from this dry processing technology.This paper highlights some of the specific issues that play a role in dry HPGR application, with respect to energy and materials balances. Examples of dry HPGR practices and process studies in iron ore mineral processing are discussed.CITATION:van der Meer, F P, Lessing, E and Matthies, E, 2015. Iron ore final grinding by high pressure grinding rolls and air classification, in Proceedings Iron Ore 2015, pp 197–204 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By D A. Williams, J C. J Boshoff

The properties of tailings that emanate from laterite nickel processing plants are significantly different to most other mine tailings. They typically comprise a mixture of fine materials that are made up of altered clays, chemical residues and salts. Neutralisation processes that are undertaken prior to tailings discharge result in a high proportion of gypsum in the tailings. The salinity of the pore fluid is commonly higher than 140 g/L of salts, dominated by magnesium sulfate. Hydraulically-placed tailings that undergo solar evaporation typically reach dry densities of less than 1 t/m3 of insoluble solids. In situ water contents after many months of drying may be as high as 80 per cent, and peak undrained shear strengths are unlikely to be greater than 20 kPa.This type of material is not conducive to upstream raising, from both a practicality and overall slope stability perspective. Even at rates of rise of less than 1 m/a, it is difficult to effect upstream raising on unaltered laterite nickel tailings. However, the authors have successfully designed and implemented upstream-raised laterite nickel tailings storage facilities. The upstream raises have been formed from both imported natural materials and air-dried and compacted tailings borrowed from the tailings beaches.Drying and associated strength gain has been achieved through various means of mechanical intervention, repeatedly exposing a zone of tailings to the atmosphere for evaporation. Field trials have been undertaken to optimise the approach, and the findings from the trials have been implemented in practice to allow stable upstream raises to be constructed. The cost savings and reduced environmental impact compared to high-volume downstream raises have been significant.CITATION:Williams, D A and Boshoff, J C J, 2015. Upstream raising of laterite nickel tailings storage facilities, in Proceedings Tailings and Mine Waste Management for the 21st Century , pp 271–280 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 27, 2015

By G Harbort, D Zoetbrood

"The Phu Kham copper-gold operation in the Laos People’s Democratic Republic (PDR) is owned and operated by Phu Bia Mining Limited. PanAust Limited holds a 90 per cent interest in Phu Bia Mining Limited, with the remaining ten per cent held by the Laos PDR Government.The original 12 Mt/a copper-gold concentrator at Phu Kham commenced production in April 2008. An incremental improvement program resulted in a number of circuit changes being incorporated by 2011, including conversion of conditioning tanks to flotation cells and the installation of a Jameson Cell cleaner scalper. In 2012 the Phu Kham Upgrade Project was commissioned to increase throughput to 18 Mt/a. In April, 2013 the Phu Kham Increased Recovery Project was commissioned to maximise performance by debottlenecking the plant IsaMill™ regrind and cleaning capacity.With the variable mineralogy of Phu Kham ore, control of the c concentrate regrind circuit is essential in terms of achieving effective liberation to maintain concentrator performance. On a routine basis laboratory regrind signature plot data is compared with daily surveys of the operational IsaMills™. More extensive surveys are also conducted to determine size distribution on a mineralogical basis and the effect of fine regrinding on pulp electrochemistry and flotation performance. This paper provides a review of the operating performance of the Phu Kham IsaMills™ with regard to power draw, feed and product size distribution, feed per cent solids, mineralogy and pulp electrochemistry. Operating performance is compared with the IsaMill™ signature plot test for predicting performance.Citation:Harbort, G, Zoetbrood, D and McNab, B, 2016. Operating Performance of the Phu Kham IsaMill™, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 39–50 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

By Swain H. D, Kay R. L

Assessment of mineral reserves in any ore- body hinges on both mineralisation characteris- tics and the economics of extraction. The mineral reserves statement depends on interpre- tation of diamond drill information by geolo- gists, determination of the production plan and operating costs by mining and metallurgical engineers and prediction of future income by economists. The techniques used to generate the mineral reserves statement for Bougainville Copper Limited in 1969 are described and the accuracy of predictions discussed. Preliminary results from a geostatistical reassessment are comp- ared with the ore zone model, blast hole data and concentrator reconciled production results.

Jan 1, 1979

By Gibbons S. L, Ritchie I. M, Murr D. M

Fundamental studies on the transformations of iron oxides have been carried out and related to the solution conditions in the Becher process. The results show that a number of iron oxide interconversion reactions occur in the aeration reactor with the products depending on the pH, temperature and oxidation potential of the aeration liquor. It is concluded that the lack of process control in the aeration reactor of the Becher process significantly hinders the ability to predict and produce high quality single phase iron oxides of a consistent colour.

Jan 1, 1990

By Quilliam B, Richmond G

Aberfoyle Ltd. has utilised a variety of flotation technologies in the Hellyer concentrator in North-Western Tasmania. Hellyer ore, with its slow flotation rates and low rate differentials between values and gangue, requires the use of long residence times and low air consumption rates in the flotation circuit. The operation of the flotation circuit, with a nominal residence time of 7 hours, has necessitated the development of a control system to provide continuity through operator shift changes. Cell selections at Hellyer varied from the 54 m3 hybrid Dorf Oliver / Maxwell (DO/MX) cells, to smaller 32 m3 Maxwell cells, conventional Don-Oliver 300 (8.5 m3) and 600 (17 m3) trough cells, and a column cell. The advantages of the large cells included low specific power consumptions and a low capital cost. However, problems with mixing and the maintenance of consistent froth depth have been identified in the hybrid DO/MX cells. Short circuiting in the trough cells was apparent, causing a considerable reduction in metallurgical performance. The column cell performs to expectation, although the application is not ideal.

Jan 1, 1991

By Toro HCH, Von Borries GH

A brief description of the semi-autogenous grinding (SAG;) facilities of Compania Minera Disputada de Las Condes is given. A data-logging and computer system was connected to the plant inter facing the existing analog control system in a supervisory s, control philosophy. The development of a control straiov,v t,) maintain maximum power of the SAG mill atsubjected to process restrictions is shownThe present control scheme is discussed inalgorithm was designed based on correlations onLween vartaoles. Associated with this, a direct level of control was developed be, on classical control algorithms, process inter-active tuning has been included. Also, an algorithm to prevent overloading of the is discussed. Control scheme tests are presented in comparison t manual operator control under the same conditions. It is shown t the control strategy gives a more stable operation and a higher plant throughput.

Jan 1, 1985

By Caelli T, Robey M

Most research into planning of open pit mines has been based on evaluation of volume-element block models in terms of their net present value. The major issues revolve around two interdependent problems the optimum ultimate pit and time-based scheduling. Despite feedback between the two problems, they are usually treated as separate tasks.The ultimate open pit is defined by the removal of whole blocks so that their net present value is maximised. This gives planners an estimate of the total worth of the venture in present terms, and is crucial to obtaining funding. All cost and profit values are assumed to be static throughout the mine life, and the only physical constraint usually taken into account is that of safe, average, wall slopes, which must be approximated by the removal of whole blocks. Modelling of any further constraints (for example, access roads and true wall slopes) is usually achieved by adding them to the optimal pit by hand. Typically this degrades the model by between five and 20 per cent of its value - which then brings into question whether it is still the true optimum.This paper reviews the dominant methods in use for this first task the ultimate open-pit planning problem. Some new optimisations are given, and the algorithms are examined in terms of their efficiency and accuracy. Finally, suggestions are made for improvement of model accuracy and eventual expansion into solutions of the more complete dual problem - that of simultaneously finding the optimum ultimate pits and dynamic schedules for the venture.

Jan 1, 1996

By P Wood, S Leveritt

This paper will introduce some innovative strategies for simulator training that are intended to improve the level of safety and operational performance of heavy equipment operators. The key strategy is to design simulator training to deliver improved work performance outcomes. This strategy is underpinned by a process for engaging workers in knowledge discovery and transfer that has been developed as an outcome of an Australian Coal Association Research Program (ACARP) funded project conducted at open cut coal mines in Australia. The process is expected to deliver improvements in the safety and operational performance of heavy equipment operators by informing training content about how experienced operators manage unexpected situations around the site. Tapping into the tacit knowledge that experienced operators gather over time can provide site specific and timely information about situational cues used to manage the unexpected. This type of information complements basic skills training by helping the trainee understand the operational context in which the acquired skills will be applied. Inexperienced operators have traditionally gained experience through their own actions, observing the actions of others and by taking the advice of mentors who have æbeen there, done thatÆ and developed operational decision making skills for safe and productive work performance. Leadership and mentoring techniques that contribute to effective knowledge delivery will also be discussed.Other simulator training strategies include refresher training, change management, emergency response training and testing the usability of new equipment and technologies prior to their introduction on-site. A key challenge ahead for the resources sector is the development of knowledge elicitation techniques that suit the operational workforce. A challenge for simulation and modelling professionals is to develop and refine techniques that support cost-effective customisation and regular updates of simulator scenarios.CITATION:Leveritt, S and Wood, P, 2012. Raising the simulator training bar - Strategies for improved work performance and effective utilisation of site-based simulators, in Proceedings Eighth Open Pit OperatorsÆ Conference , pp 65-70 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 18, 2012

Backfil ling of excavated Sub Level Open Stopes has been underway since March 1989 and as at December 1992 some 1 100 000 cubic metres of Cemented Aggregate Fill have been placed. During these three years significant developments in fill quantities, types and cost have taken place.Operational improvements have reduced the quantity of Cement Aggregate Fill by 40 per cent. These results have been achieved by:ò rescheduling stopes,ò designing smaller primary stope, and ò use of uncemented rockfill.Unit cost for Cement Aggregate Fill have fallen in the order of 50 per cent through:improving fill hole reli ability,simplified barricade construction procedures, reducing the cement content,ò substituting dune sand for deslimed mill tailings, ò improved maintenance at the Backfill plant, and ò renegotiated site freight agreement.This paper will review the historical developments of backfill use at Olympic Dam.

Jan 1, 1993

By R F. Sandenbergh

Due to environmental considerations, mineral processing plants are increasingly recycling water to decrease the impacts of wastewater on environment and the depletion of fresh water resources. Industrial experience has shown that increasing recycling water in flotation typically negatively impacts the recovery and selectivity, especially in the selective flotation of minerals from complex sulfide ores. The major reason for the reduced selectivity is typically the inadvertent activation of sphalerite or pyrite by the heavy metal ions (HMI) in solution. These HMI are often produced during milling and flotation and absorbed by other minerals. In the normal flotation pH value range (8 - 10), these HMI are often in the form of precipitates or complex ions that may re-appear in solution or become active should conditions favour this. In this paper, microflotation, batch flotation and XPS surface measurement were used to investigate the use of HMI absorbents additions to the pulp to improve flotation selectivity of a complex sulfide ore. It has been demonstrated that HMI removal does improve flotation selectivity by facilitating more effective depression of the sphalerite. Microflotation and XPS surface measurements have shown that HMI absorbents compete with sphalerite to absorb HMI, and thus reduce the surface concentration of HMI on those sulfides. The practical use of HMI absorbents in complex sulfide ore flotation is also discussed.

Jan 1, 2005

By S Jeon, K Haga, A Shibayama, L Godirilwe, C B. Tabelin, I Park, A Buronov

Open pit/underground mining and mineral processing can generate large amounts of waste that contains sulfide-type minerals such as pyrite (FeS2), and it can produce acid mine drainage (AMD) when exposed to oxygen and water. This highly acidic wastewater contains heavy metals and this is one of the most serious environmental issues after mining operations taking several decades to completely remediate with high costs. For green mining, the present study focused on the development of a recovery technique for gold from an eco-friendly solvent, thiosulfate, by utilising mine wastes, tailings. First, gold recovery experiments in ammonium thiosulfate system were carried out using model samples representatively present in tailings (ie SiO2, Al2O3, FeS2, Fe2O3, and Fe3O4). The results showed that gold recoveries were negligible when using Al2O3, SiO2, Fe2O3, and Fe3O4 while pyrite shows a recovery efficiency three-fold as high as the maximum recovery efficiency when using others. Subsequently, the study also addressed the identification of the recovery mechanisms and post-recover process. The results indicate that tailings can be sufficiently utilised for gold recovery in the hydrometallurgy process and a further sustainable process can be established.

Sep 1, 2024

By R Ahola, M D. Henschel, M A. McParland

With the introduction in recent years of third-generation interferometric synthetic aperture radar (InSAR) techniques, monitoring of mine slopes, benches and surrounding areas has benefitted from increased accuracy and coverage. Fundamental research into point and distributed scattering techniques has pushed the use of InSAR to provide higher spatial and height resolution. In this paper we discuss the operationalisation of third-generation InSAR techniques and show its application to active mining operations.This paper will discuss the use of multiple independent measurements of ground movement obtained from operationally-derived InSAR products over a wide variety of deformation areas within an active open pit mining operation (ie pit slopes, dewatering depressions, tailings containment and waste dumps). A technique that shortens the time between observations (increased observation frequency) and provides ongoing estimates of measurement accuracy will be described. The methodology exploits available satellite data by using multiple satellites and multiple beams. The paper will also examine factors in the design of a mine survey with third-generation InSAR and illustrate some of the necessary engineering trade-offs to efficiently monitor a mine from space.Overall, this paper aims to demonstrate the capabilities and advantages of operational third-generation InSAR techniques for ground movement monitoring of mining operations and provide a framework for proper design of a mine InSAR survey.CITATION:Henschel, M D, Sato, S, Ahola, R and McParland, M A, 2014. Designing interferometric synthetic aperture radar surveys for mine monitoring with accuracy assessment, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 233–238 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014

By I H. Wilson

After decades of turmoil, Rwanda launched its Vision 2020 in 2000 aimed at reconstructing government and addressing poverty. Implementation focused on the agricultural sector, infrastructure and education. Later economic development and poverty reduction strategies recognised that expansion of tantalum, tin and tungsten mining could potentially diversify Rwanda’s economy and improve the balance of trade. In 2005, comprehensive environmental legislation requiring environmental impact assessment for all new mines was introduced. Since 2006, government-operated mines have been privatised and illegal artisanal miners encouraged to form cooperatives. The government passed a new Mining and Quarry Exploitation Law in 2008 and approved a new Mining Policy in 2010. This policy was influenced by the Africa Mining Vision (AMV), which the African Union approved in 2009 to ensure African countries obtain reasonable benefits from exploitation of their mineral wealth. The Rwandan mining industry has grown significantly over the last five years and the second economic development and poverty reduction strategy, released in September 2013 forecasts a further three-fold increase in production in the next five years. The strategy prioritises the mining industry and proposes new legislation, better information, greater transparency, encouragement to investment and use of best environmental and technical practices. It also proposes that Rwanda develop a ‘green’ mining sector featuring a ‘model’ mine that is fully funded through green investment and incorporates renewable energy systems, water treatment systems, forestry schemes and local training. Many international development partners have contributed to the current legislative framework and are monitoring environmental and social performance of mining in Rwanda. Local communities have generally benefited from mining and the new mines show improved environmental performance. The major challenges are dealing with the legacy of past haphazard mining practices and establishing linkages between the mines and local industries to create broader economic development.CITATION:Wilson, I H, 2014. Rwanda and the Africa mining vision, in Proceedings Life-of-Mine 2014 , pp 427–438 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

By B E. McCarthy

Red Dome Mine was a highly complex gold copper operation developed over a number of phases between mid-1986 to October 1997. With only three years of production ahead at any time, a proactive practical approach to mine closure was necessary. In 1989 the Domains Concept to life-of-mine planning and mine closure was created as a response to the proposed changes to legislation.The Domains Concept, a relatively simple idea developed to integrate mine closure during production at Red Dome, has been broadly adopted by both government agencies and industry in the intervening 20 year period. Over time the author has observed that the concept has been poorly applied, misunderstood and in some cases even misrepresented. As a consequence, the potential opportunities from applying the concept, including the optimisation and minimisation of life-of-mine costs, mitigation of long-term financial liability exposures and building credibility with the general community, have been missed.This paper examines the many benefits, advantages, applications and perceived barriers to developing and integrating a fully costed life-of-mine plan. Integrating the Domains Concept early in the project, within the operational budgeting, allows the production of a meaningful and useful document, representative of a whole life-of-mine, cradle to grave, with measurable rehabilitation and closure outcomes when the concept is used to full effect.The Domains Concept serves to optimise cost-effective, whole of mine, life cycle planning which provides beneficial outcomes for the community, significantly mitigates legacy issues and contributes to the attainment of compliance and sustainability principle objectives.CITATION:McCarthy, B E, 2014. The domains concept – 20 years on retrospective, obstacles and opportunities for effective life-of-mine implementation, in Proceedings Life-of-Mine 2014 , pp 621–636 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014