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By R Soong

The Wharekirauponga (WKP) epithermal gold-silver deposit is located about 10 km north of Waihi in the Hauraki Goldfield east of Auckland. WKP is notable for its sheeted to stockwork quartz veins hosted in rhyolitic rocks, that have attracted exploration interest as a low grade, bulk tonnage exploration target. Exploration between 1978 and 1993 included 23 diamond drill holes totalling 5505 m. The mineralisation occurs in a rhyolite dome complex (Miocene), consisting of flow-banded rhyolite and rhyolitic pyroclastic rocks, with minor andesite. Fifty four drill core samples were collected from six exploration drill holes and analysed by semiquantitative XRD techniques. Hydrothermal alteration of the rhyolitic and andesitic rocks has developed secondary mineral assemblages of quartz, adularia, albite, chlorite, illite, sericite, interlayered illite-smectite, carbonate, halloysite and pyrite. The main zone of mineralisation is characterised by quartzadularia alteration, which grades oiItward to quartz-clay (illite, local halloysite and/or interlayered illite-smectite) alteration. Propylitic alteration is present at the southern end of the drilled area of the prospect. Depth-related changes in mineralogy include a decrease in illite and appearance and increase in quantity of chlorite with increasing depth, and the localisation of halloysite and interlayered illite-smectite in the shallow parts of some drill holes.

Jan 1, 2001

By Fookes R. A, Bunch K, Gravitis V. L, Watt J. S

The combustible volatile matter in coal mine roadway dusts (CVM) has been determined using x-ray backscatter techniques. The correlation between x-ray and chemical techniques is reasonably good for the 92 samples from collieries on the Bulli seam, and the maximum error expected at the maximum level of 11· 5 weight per cent CVM permitted in the N.S.W. Coal Mines Regulation Act, 1912, as amended, is about ± 2·5 weight per cent. This x-ray technique can be used only when the combustible volatile content of the coal matter (cvm) varies within a limited range, and a separate calibration is required for each coal seam.Portable equipment based on a radioisotope x-ray source ahd digital ratemeter makes possible simple and rapid analysis, and with adaptation to use in coal mines should lead to much more comprehensive testing- ofroadways and hence improved overall prevention of coal dust explosions.

Jan 1, 1977

By A Hughes, S G. Rosin

This paper presents the design and construction approach adopted for the widening and stabilisation of the existing decline tunnel forming part of the Scenic Railway Upgrade project at Katoomba in the Blue Mountains of New South Wales (NSW), Australia. The overall upgrade project included new trains and track, rebuilding of the top and bottom station and installation of a new winch and control system. All the works were undertaken over an eight-month period between August 2012 and April 2013 as part of a $30 M upgrade of the railway.The railway is the steepest cable-driven line in the world at a maximum of 52° extending over 350 m and descending from the escarpment into the Jamison Valley. The track was built in the 1880s for coal haulage and is recognised as a remarkable engineering achievement for its time. The tunnel section extends for about 120 m at the start of the decline and is about 3.5 m wide and 3.5 m high. The tunnel was excavated principally within medium to high strength Banks Wall sandstone and given that the widening only involved about 200 mm of trimming of the crown and sidewall this aspect of the work was not a critical support issue, except at the upslope portal. The tunnel crown however is entirely intersected by a major near vertical shear zone which presented significant challenges for the tunnel stabilisation works.Three-dimensional laser survey scanning was used for definition of the tunnel clearance envelope for the widening, and also to subdivide the tunnel into various geotechnical sections to assist in support design. Specifically oriented rock bolts extending beyond the shear zone into stable rock were used together with mesh, shotcrete and extensive strip drains and flushing points for drainage of the shear zone.Unique aspects of this project were included into the specifications and work methods. This included construction of a mobile working platform for tunnel works, the use of dry shotcrete application, difficult access for rock bolting and limiting vibration during the tunnel trimming works due to the risks associated with crown instability. The works also took into consideration particular safety constraints/work exclusion areas to address the risk of detachment of rock which could mobilise downslope to the track area below. This was required because other works were in progress such as micro-piling and bottom platform works which were being undertaken concurrently with the tunnel work.CITATION:Rosin, S G and Hughes, A, 2014. Scenic Railway Tunnel upgrade in the Blue Mountains, New South Wales – an approach to design and construction, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 607–618 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

As the chief field of the gold dredging industry in Otago is the district traversed by the Molyneux River (called above Cromwell the Clutha) and its tributaries, a brief reference to the geology of that region and the origin of its alluvial gold will not be out of place. The prevailing rocks are metamorphic schists, chiefly mica and quartz schists, pr.obably of Silurian age. Though these rocks do not contain many payable quartz reefs, gold appears to be distributed in small quantities all through them,chiefly associated with the quartz lamime and lenses. The river drift, however, contains numerous pebbles of quartzite, quartzoze conglomerate, and fme-grained slate. Seeing that these rocks are hardly known to occur in situ within the watershedof the Molyneux River, though Devonian and carboniferous rocks of similar character occur to the north-east and south-west, it seems probable that the schists were at one time overlaid by carboniferous and Devonian rocks, and that these have been removed by denuding agencies. Be this as it may, it is certain that the schists themselves have been greatly eroded by the action both of water and of ice, and that the resulting drifts have themselves, in many cases, been sorted and re-assorted by the same agents.Consequently the drifts are very varied in character and often developed on a grand scale. In geological age they vary from Early Tertiary (though some may be older) to Recent.

Jan 1, 1903

East Otago gold deposits are hosted in Otago Schist that is the metamorphosed equivalent of Permian-Triassic Torlesse terrane greywackes. Relatively undeformed Torlesse sequences in Canterbury have <l m - 50 m bedding, with c. 500 m - l km and c. three kilometre scale units, typically either: 1) thick-bedded, massive, sandstones; 2) thin-bedded sandstone-argillite flysch; or 3) siltstone- or argillite-dominated units. Such lithological layering in Otago was intensely folded, deformed, and overprinted by metamorphic fabrics during Jurassic-Cretaceous regional metamorphism. Although primary sedimentary structures can no longer be recognised, a æghostÆ lithological variation is still present in Otago represented by psammitic (sand-derived), interlayered (sandstone-siltstone derived) and pelitic (siltstone-mudstone derived) schist. Lithological æunitsÆ in the schist are typically either 20 100 m or c.1 - 2 km thick, and are oblique to faults and shears hosting gold mineralisation at Macraes, Barewood, Nenthom, and Oturehua. Lithological variations and folds in lithological units are important in the along-strike distribution of gold in these deposits, and in the development of relatively high-grade pods and shoots at l00 m - 1.5 km scales. Ramps, flats and step-overs (known to be locally important for controlling mineralisation) are commonly located at lithological boundaries, presumably by local refraction of faults or shear zones as they propagated through folded stratigraphy. The various lithologies have also responded differently to deformation, causing variations in permeability that affected the penetration of mineralising fluids. Mapping lithological variations in barren host-rocks, either directly+ by fieldwork or indirectly by aerial geophysics, is a key to understanding and predicting the distribution of gold at mine and deposit scales.

Jan 1, 2001

By I Lourel

In evaluating the installation of an in-pit crushing and conveying (IPCC) system for any mine, a number of options are available for each of the dig side, transport and dump side operations. Some of them are moreappropriate than others; given the pit arrangement, the material being handled and the rates at which it needs to be moved. This paper seeks to document the options that might be employed, and to rank them in terms of their applicability at any mine and their practicality overall, with a view to nominating those that would be most suitable for further study.

Jan 1, 2009

Behaviour of Bubble Clusters in a Turbulent Flow

Sep 13, 2010

By P Corbett, P Sheffield

Springvale Mine is an underground coal mine in the western coalfield of New South Wales which utilises retreat longwall mining technique. The mine encountered significant gateroad floor heave issues during retreat of LW415. Floor heave has subsequently impeded longwall advance as well as longwall bolt up and recovery to some extent during the extraction of the next five longwalls. Floor heave at Springvale Mine develops throughout the lifecycle of the mine roadways, and is most prevalent in longwall gateroads. Floor heave has been measured as early as 2 weeks after roadway development and continues to develop through the post-development phase, with a rapid increase in close proximity to the longwall face. This paper presents a case study of the evolution of understanding of floor heave behaviour at Springvale Mine based on geotechnical characterisation, an intensive convergence monitoring program (roof and floor movement) and spatial correlation of monitored locations with longwall face position. The analysis considers previously known factors contributing to floor heave including mining depth, geological and physical properties of the rock mass and mine design geometry. Investigation results indicate a strong correlation between floor heave magnitude and roof dilation magnitude, geophysically inferred faulting in underlying strata, areas of localised stress concentration and mine roadway dimensions. This paper also discusses the predictive model which was developed as a result of the study, which is now the basis of the floor heave removal program used to manage roadway convergence at the mine. Floor heave monitoring, prediction and management strategies (including floor reinforcement and removal) are also discussed. CITATION:Sheffield, P and Corbett, P, 2018. Managing floor heave in an underground longwall coal mine, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), pp 78–94 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

By A Kamkar-Rouhani

The paper describes a mineral potential mapping of gold and other base metals in Mahneshan area, Iran, using geographical information system (GIS), in which, the method of weights of evidence is used to combine spatial data obtained from different sources to make prediction for mineral potential. This is a quantitative tool for mineral resource mapping that can be used to delineate and predict favorable areas for further exploration by using the characteristics of known and similar mineral deposits. In accord with the descriptive model for gold and other base metal deposits, the spatial distribution of 20 known mineral occurrences was used. In addition, digital evidential maps were used in this study. The maps include maps of lithological units, faults and first derivative of total aeromagnetic data, remotely-sensing data of alteration and also geochemical evidential maps produced on the basis of the results of chemical analyses of samples taken from the stream sediments in the area, and analysed for Cu, Pb, Zn, Sb, As, Ag, Au, Ba and Hg elements. The binary maps were produced and then combined with the model of weights of evidence using 20 known mineral occurrences to obtain a final map of the favourable areas for further exploration of gold and other base metals in the study area. The final map is a predictive GIS model of the mineral deposits in the area. An interesting matter about the final predictive GIS model is that the faults are mainly located in favorable areas which possesses the most probability of mineralisation. Therefore, the faults in these areas have priority for further exploration of gold and others base metals.

Jan 1, 2005

By R Belissont, C Veloso, L Senez, F Vasconcelos, E Kleiderer, J Mesquita, Y Basselin

Mont-Wright mining complex is an important asset of ArcelorMittal located in the province of Quebec, Canada. It is composed by Mont-Wright and Fire Lake mines, operating 365 days per annum, and producing 25 Mtpa of iron ore concentrate with 66 per cent Fe. Mont-Wright concentration plant is composed by seven lines with a flow sheet encompassing AG/SAG milling, primary and secondary classification stages, spiral concentrators (rougher, cleaner and recleaner stages) and dewatering unit operations. In this context, an equation called ‘Wrec’ was developed in 1971 with the objective of estimating the mass recovery of the different blocks in the beneficiation plant and support the mining planning works of Mont-Wright complex. This equation was based on the correlation between the results of heavy liquid tests performed with drill core samples and spiral concentrators pilot scale tests, returning an estimative of concentrator yield. However, since its first development, no updates have been done in the equation, which lead to some deviations from expected recoveries in the last years. This is probably due to the changes in the process and in the ore fed into the concentrator during the period. In this way, the study presented here corresponds to the execution of heavy liquid/spirals pilot scale tests with 26 composite samples collected at Mont-Wright deposit aiming at revising and updating ‘Wrec’ equation. Based on test work results, an updated formula was established to estimate the plant recovery and a comparison performed using industrial data showed that the old formula overestimated the real yield by 5.40 per cent, on average. At the end of the study the new equation was incorporated into the mining planning process.

Sep 18, 2023

By R Badreddine, J Rose, L De Windt, P Chaurand, L Raimbault

Municipal solid waste of incineration (MSWI) bottom ashes are recycled as aggregates in civil engineering. These heterogeneous materials are composed of crystalline and glassy solid phases which contain trace metals, presenting a potential risk to the environment. Secondary ion mass spectrometry (SIMS) can provide quantitative chemical information, in particular the localisation of metals at trace level. Unstable glassy phases formed during incineration are present in relatively high proportions. Their analyses suggest a continuum between melilite-bearing glasses and dark glasses enriched in iron with abundant spinel aggregates. These primary glasses are enriched in zinc (~4500 ppm) but depleted in lead (~800 ppm) by comparison with the bulk chemical composition and reference materials. Heterogeneous cementing and encrusting admixtures on coarse grains are studied in a second step. SIMS imaging suggests a superposition of band zones including an intermediate layer enriched in iron oxyhydroxides and a superficial layer with calcium accumulation. A strong spatial association between lead and iron is systematically observed. Extended X-ray absorption fine structure (EXAFS) supports these observations by demonstrating that lead co-precipitation within iron oxyhydroxides, or sorption on their surfaces, may be a main containment process in the cementing and encrusting admixtures, whereas lead speciation is globally more complex in MSWI bottom ash.

Jan 1, 2008

By Brosnan J. G

Simcoa Operations is the only silicon smelter in the region and since the plant was commissioned in late-1989, has progressed from supplying silicon metal to the secondary aluminium market to the current position of supplying in excess of 90 per cent of its production to the high quality chemical and primary aluminium markets. This position has been achieved through the unique advantage which Simcoa has developed within the industry, namely raw materials, people and Simcoa's ability to adopt and use modern technology. A quality culture was instilled into the workforce prior to commissioning which ultimately led to AS3902 qualification in 1992. Simcoa has continued its quality drive through the formation of 'Simcoa's Quality Leadership Process' which is planned to make Simcoa the best silicon producer in the world.

Jan 1, 1995

By D David

The development of Western Australian magnetite deposits has lead to the design of some of the largest grinding mills and plants in the world. One of the projects demonstrates the efficiency gains possible by developing a simple yet thorough test program for circuit design. By drawing on the experience of current magnetite operations in Australia and the Mesabi and Marquette iron ranges in the United States, a basic flowsheet was developed. Through comprehensive testwork with AG, ball and stirred milling the flowsheet was optimized to take full advantage of each grinding mill’s strengths to reach the required final grind size. Laboratory work was verified in the pilot plant to optimize the energy efficiency of each grinding step while ensuring adequate liberation at each step for sufficient gangue rejection. By using three stages of grinding, the ball mill can best be employed in ensuring all top size gangue material is liberated and removed in the second magnetic separation step. The inclusion of the IsaMill, with its inherent steep product size distribution, as the tertiary grinding stage ensured that maximum grade was achieved and simplified the downstream process while giving further improvements in total grinding capital and operating costs. In this way the combination of the two technologies downstream from the AG mill is far more efficient than either would be on its own by reducing the total installed power by 1/3 and annual grinding media cost by 2/3.

Aug 8, 2011

By T J. V Duffy, L H. D Siahaan, P G. Albert

G-ResourcesÆ Martabe Mine in North Sumatra, Indonesia, is a US$700 M world-class and world-scale operation in a country which, with a few notable smaller scale exceptions, has had no significant hard rock mining development in more than ten years.The mine was commissioned in the middle part of 2012 and poured first gold on 24 July. At full production Martabe will produce 250 000 oz/a of gold and 2 - 3 Moz/a of silver at cash costs in the lowest quartile. The mine location is on the west coast of North Sumatra, which experiences annual rainfall of 4 m with no notable dry season, adjacent to seismically active fault zones, and relatively close to a rural community of 31 000 people with no significant industrial experience.The management team has successfully forged strong links with the various government departments and levels in Jakarta, North Sumatra Province and the local Regencies; developed long-term relationships with the various community groups within the local district of Batangtoru to build a sustainable social licence; has dealt with the physical and environmental challenges presented by the project location, and has successfully raised more than US$900 M over a period of three years for the original acquisition then the development of the project.Whilst in its infancy of operation, the mine is set up to deliver a long-term sustainable future for the company, the shareholders, and the people of Batangtoru and all stakeholders generally. The quality of the project execution and commitment by the company will ensure that maximum value can be delivered from Martabe, not just for the current mine life but from the significant exploration potential that exists on the large tenement area that the company has access to for 30 plus years.This paper will deal with the physical challenges associated with the design, the Indonesian government regulatory requirements for mine development, the social aspects of building a world-class project in a developing area, the in-country commitment necessary for any project development anywhere in the world and the successful funding arrangements for the mine development.CITATION:Albert, P G, Siahaan, L H D and Duffy, T J V, 2012. Building AsiaÆs latest hard rock mine, in Proceedings International Mine Management 2012, pp 189-204 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 20, 2012

The information age has arrived. In every aspect of life, at the end of the second millennium, computers and information technology have made significant inroads. In mining there has been huge growth in the use of digitally controlled systems. From resource evaluation to mine planning to daily operations, information is being acquired, analysed, modeled and presented, using state-of-the-art information technology. Explosives, too, have moved into the information age. Computer controlled trucks and manufacturing plants have been developed and are now a regular feature on many mine benches. The next challenge for the explosives industry as a whole is to integrate blast initiation with information technology. The benefits are there, both to the supplier and to the end-user. Much has been written in the past about the potential for blast improvement but there are other significant advantages to a digital initiation system. These include security from unauthorised use, stock control and minimisation, reliability through testability and ease of use to name a few. So why is it taking so long? Surely the complexity of an electronic initiation system is far less than that of mobile phones that have been around for a long time. The answer, it seems, lies in the level of new technologies that need to be developed. There are enormous technological hurdles to be overcome in order to put into the market a cost-effective, reliable, user-friendly electronic initiation system. The most significant of these are:Safely and reliably initiating an explosive from an electronic device powered by a small capacitor. Prior to the development of electronic detonators primary initiation of explosives was by shock tube spit or by passing large currents and voltages down a pair of wires. Electronic detonators do not have that luxury. For example the energy stored in a æBeethovenÆ exploder is more than 500 times greater than that available to an electronic detonator. Communicating to a multitude of devices over very long cables installed by miners in harsh conditions. The deployment of an electronic detonator system has been likened to building a large telephone exchange in the rain and getting it to work perfectly first time! New communications protocols needed to be developed and tested. Wiring and connection systems have to be designed to survive the mining environment. In spite of these technological hurdles most of the major explosives manufacturers have persisted with electronic initiation systems and we are now, in 1999, starting to see the results of these multi-million dollar efforts. At SMI we are often asked many questions about this technology. The remainder of this paper seeks to answer those most often asked. As with any business linked to information technology todayÆs breaking news is tomorrowÆs archive and we expect the rate of development and understanding to accelerate as these technologies become accepted by the global mining industry.

Jan 1, 1999

By N Pirouznia, F Rashidi Nejad, S Naraghi

Sungun Copper Mine, which is the second largest copper mining operation in Iran has a large tailings storage facility with a seepage control dam located downstream of the main dam. Surface and groundwater in surrounding area of the tailings storage facility has been monitored for ten years. This paper will discuss the results of the surface and groundwater monitoring and seepage control at the Sungun Copper Mine. The results of the study show that if the tailings storage facility influence the water quality of the rivers, this effect is not significant, so that the prevailing parameters of the measured parameters were within the permissible standard of drinking water in Iran.CITATION:Rashidi Nejad, F, Naraghi, S and Pirouznia, N, 2018. Surface and groundwater monitoring and seepage control at the Sungun Copper Mine, in Proceedings Mine Waste and Tailings Stewardship Conference 2018, pp 439–453 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 23, 2018

By T Higuchi, K Fukada, K Takehara, Y Iwami, S Fujiwara

Following the Paris Agreement adopted in 2015 and the SDGs, reduction of CO2 emissions has been taken up as an issue worldwide, and the steel industry, which has a particularly large emission, is required to significantly reduce it. Most of the CO2 generated in the steel industry is generated from the ironmaking process, due to the use of coke and its raw material coal in the ironmaking process. JFE Steel Corporation has been considering the use of hydrocarbon-based gaseous fuels and liquid fuels as a partial alternative to coke breeze used in the sintering process since 2006, immediately after the Kyoto Protocol came into effect in 2005. In a laboratory study, a pot test was used to investigate the effect of the type of fuel, its amount and its injection method on the heat pattern in sinter bed. As a result, the authors developed a technology, in which a predetermined amount of gas fuel or liquid fuel was injected from the surface of sintering bed to extend the holding time of 1200°C or higher at which liquid phase sintering occurs in the layer, to improve the sinter strength while reducing the amount of coke breeze. The authors succeeded in putting this technology to practical use using hydrocarbon-based gas fuel in 2009 and achieved a maximum annual reduction of 60 000 tons of CO2 per sintering machine. In this report, the authors introduce the results of laboratory studies on the use of various energy sources, the practical application of the technology for injecting hydrocarbon-based gaseous fuel into the sintering machine, and the operational results.

Nov 8, 2021

By B Smith, R Gelson

Springvale Colliery is an underground longwall mine situated approximately 10 km north-west of Lithgow in the western coalfields of New South Wales. Following a full-scale review of the mineÆs ventilation system in mid-2010, it was clear that the mine by early 2013 would become ventilation constrained as a result of the increasing size of the mine workings, the predicted worsening tailgate conditions and plans to introduce a fourth continuous miner unit. This realisation led Springvale to embark on a major upgrade of the mine ventilation system that would meet short-term and life-of-mine (LOM) requirements.Included in the upgrade project was the installation of a new high pressure centrifugal main exhaust fan that is capable of overcoming the high resistances imposed frequently on the circuit by restrictions in the tailgate airway. The new fan featuring a 2.5 MW motor is designed to be capable of operating at a quantity of 250 m3/s at a pressure of 7.9 kPa, a substantial improvement over the previous system, which had an operating duty of approximately 145 m3/s at 1.9 kPa. The new fan is of a centre hung design and features a backup diesel motor to maintain ventilation in the event of a power outage.Structural engineering analysis determined that under the operation of the new main fan the existing standard of ventilation control devices (VCDs) at Springvale would not be adequate to withstand the increase in differential pressures. As such, an upgrade of critical VCDs was undertaken utilising a novel high flexural strength (9 MPa) shotcrete and thin spray-on liner, which help serve to safeguard the structural integrity of the appliances and prevent increased leakage as roadway conditions at VCD sites deteriorate over time (a serious problem in many areas of the workings at Springvale).In addition to the main ventilation system upgrade, a separate upgrade focusing on improving development face ventilation was also undertaken. This upgrade included the purchase of two high capacity (22 m3/s) variable inlet vane (VIV) auxiliary fans to facilitate comfortable development face ventilation.The upgrade of the mine ventilation system at Springvale has been three years in the making, but has removed a major business risk in that it has afforded mine planning and operational flexibility (a fourth unit can now be introduced) for the LOM, and importantly provided unprecedented levels of comfort to operators at the working faces where previously ventilation and heat issues were frequently reported. The impact of this on the morale of the workforce, and hence their output, should not be underestimated.CITATION:Gelson, R and Smith, B, 2013. Life-of-mine ventilation system upgrade at Springvale Colliery - A case study, in Proceedings The Australian Mine Ventilation Conference , pp 79-86 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 1, 2013

By Y K. Ji, B J. Chung

In recent years, the utilisation of ultra-fine ore in ironmaking has gradually increased due to the depletion of high-quality iron ore. The use of ultra-fine ore in the ironmaking process is typically energy intensive and leads to high CO2 emissions. The improvement of sinter reducibility is one of the methods used to reduce the environmental impact of using fine ore.In this study, a high-strength and high-reducibility sinter manufacturing process was investigated by controlling the sintering reaction. The key technology used in this method is the manufacture of mini-pellets by selective granulation equipment. The mini-pellets consist of iron ore, limestone and burnt lime and are designed to melt at temperatures below 1200°C. The molar ratio of CaO to Fe2O3 of the mini-pellets is 0.25~0.75. The 2~5 mm diameter mini-pellets are manufactured with burnt lime as the binding material.During the sintering of mini-pellets, goethite, which has relatively high reducibility, should be retained as residual ore in the sinter cake. The strength of the sinter cake was kept by the bonding reaction of the mini-pellets, which have a low melting temperature. This is the main principle of the reaction-controlled sintering method.The reaction-controlled sintering method manufactures a high-strength and high-reducibility sinter cake and increases sinter productivity by around 15 per cent using ultra-fine iron ore.CITATION:Chung, B J and Ji, Y K, 2015. Production of high-quality sinter by controlling the sintering reaction, in Proceedings Iron Ore 2015, pp 21–28 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By G Pasin, F Wirfiyata, G Khomaeni, W Valery, A Maclean, A Jankovic

The grinding circuit at PT Newmont Nusa Tenggara (PTNNT) – Batu Hijau mine consists of two SABC (semi-autogenous milling, ball milling, pebble crushing) trains, including four 20'?×?33'6? ball mills that have been lined with steel liners since the commissioning of the plant in 1999. During 2011 and 2012 an industrial trial was conducted to evaluate Poly-Met liners (a combination of rubber and steel liners). These new liners were installed in two of the ball mills (ball mills 1 and 2) and operated in parallel with ball mills 3 and 4 with steel liners.The objective of the trial was to compare the plant performance with the Poly-Met and steel ball?mill liners with regards to wear life, mill throughput, grind size and total unit costs. The trial was conducted over the entire life of the liners. The evaluation methodology implemented consisted of frequent spot sampling around the ball mill circuits, complete surveys/audits in both ball mills, and detailed analysis of process data. This paper presents the results of the industrial trial and main conclusions.CITATION:Maclean, A, Wirfiyata, F, Khomaeni, G, Jankovic, A, Pasin, G and Valery, W, 2014. Ball mill Poly-Met liner evaluation at PT Newmont Nusa Tenggara – Batu Hijau mine, in Proceedings 12th AusIMM Mill Operators’ Conference 2014 , pp 255–262 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 1, 2014