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By Collier D

The topaz resource at Torrington in northern N.S.W is currently the subject of a joint research and development programme managed by Pacific Copper Ltd, This programme has culminated in a pilot topaz calcination plant, located at Parramatta, which, through its operation, will establish the commercial viability of developing this mineral as an industrial raw material for both the refractory and fluoride chemical industries.

Jan 1, 1989

By Bertrand D. L

Although investigations into treatment of Mt. Keast (a hill of tailing) began as early as 1940, it was not until the Imperial Smelting Furnace (I.S.F.) was installed at Cockle Creek by Sulphide Corporation that its treatment became eooncmically feasible. Early investigations and milling operations which began in mid-1976, with their developments are described. Metal recovery involves sulphide flotation, oxide flotation and gravity techniques.

Jan 1, 1983

By M Hopkins, A Mutale, A E. Vidal da Silva

The Cliffs Nickel Mine extracts a narrow near vertical nickel vein using a mining method of underhand bench stoping with paste backfill. In 2014, at a depth of 400 m below surface, the Northern block of the mine began to experience squeezing within ore development. At first the deformation was localised, within 30 m of the stoping front, but later became pervasive extending across the Northern block and resulting in a hiatus in mine production. The global mechanism is a progressive pillar failure, where the inter-level pillars in advance of the production front could no longer withstand the induced load and progressively yielded. The local mechanism of failure was observed as crushing of the massive sulphide ore and ‘punching’ of the pillars into the ultramafic hangingwall exhibited as floor and sidewall dilation and unravelling of the mafic footwall. The cause of the global mechanism was attributed to a combination of factors, including: high overall extraction ratio, small vertical pillar heights between ore development, high stress in relation to the low rock mass strength, shallow stope front angle, and insufficient ground support capacity. Following the progressive failure, the remnant rock mass conditions across the northern block were severely degraded, with numerous falls of ground that led to a reassessment of the mine plan. Recovery of the Northern block started in 2016 as a staged process. Development of the safe recovery work methodology involved a number of considerations, such as: production sequencing, development access design, ground support, and development of specific procedural controls. The Northern block was then broken into smaller mining precincts based on tactical factors such as location, ease of access, scale of rock mass damage and nickel content. A specific ground support standard and work methodology are employed, while cycle sheets are used to ensure quality and completeness of work. Large intersections showing signs of deformation have either been bypassed or treated using Rocprops to maintain stability during stope production. This approach has been successful in safely regaining access and restarting production in areas that had previously been removed from the mining reserve.

Mar 15, 2021

By J J. Moreno, J Willis, P Garvey

Many of the tailings storage facilities (TSFs) in Australia are upstream raised facilities for which the consolidation of the hydraulically deposited tailings is essential to the stability of the TSF. While much operational consideration is given to limiting the rate of rise of TSFs through careful management of deposition rates to achieve desired consolidation, the rate of embankment raise construction (RoC) is often not given the same level of consideration. Loading the tailings at too high a rate during construction could lead to upstream and potentially downstream failure of the embankment. The Tailings Retention System (TRS) at the BHP Olympic Dam Mine comprises upstream raised TSFs that are continually raised with a zoned embankment. Improving on 20 years of successful embankment raising, there was a desire to understand the acceptable RoC under varying operating conditions and assess upper construction limits to improve operational risk management. To understand the RoC, trial embankment raise construction pads were constructed at different rates and the pore pressure response of the underlying tailings material was monitored. The pore pressure data were used to calibrate the permeability and consolidation characteristics of the tailings in a finite element model (FEM) that replicated a typical embankment raise. The rate of material placement, location of the phreatic surface and construction load were varied in the FEM until failure was initiated. The results were presented as a period (in days) over which the various zones for the embankment raise could be safely constructed. The results indicate direct sensitivity to the depth to the phreatic surface prior to commencement of an embankment raise, as well as the point of application of the construction traffic load. This paper presents the study approach, challenges experienced in modelling the construction methodology, the study results and their relevance in the improvement of understanding of RoC at the BHP Olympic Dam TRS.

Jul 1, 2021

By Ryan CG, Cousens DR, Suter GF, Griffin WL

A novel method utilizing PIXE with microbeams following fire-assay has been developed to determine PGE and Au at sub-ppm levels suitable for application in exploration. Analyses of the prills from the lead and silver fire-assay yield Pt, Pd and Au concentrations readily. NiS must be used as collector if the complete suite of PGE is required, but this method is not as Convenient.

Jan 1, 1989

In the sixteenth century the Spanish Captain da Alvaro Soavedaro, on a search for the explorer Ferdinand Magellan, came across the main island of New Guinea which he named Isla del Oro (Island of Gold). Since that time exploration for, and mining of, gold has been pursued by many, culminating in . the development of major world-class projects in the latter part of the 20th century. Though various prospectors have panned for gold and small gold mining projects were undertaken through the seventeenth and eighteenth centuries, it was not until the 1880's when mining became a more concerted economic venture. Misima and Woodlark Islands in Milne Bay, Gura-Ackera and Yoada in Oro, and Lakekamu in Gulf Province and Keveri in Central Province were all gold producers by late nineteenth century. It was in the 1920's that corporations began mining in PNG and with the commencement of production at Panguna in Bougainville in 1972 a new era of mega-project mining began.' Today there are two large mining projects producing mainly gold and copper. The first, already mentioned, is Panguna on Bougainville Island. This project has provided Government with $US 475 million in taxes. ok Tedi is the second large mine development located in Western Province. It began production in 1984 with the extraction of the deposit's "gold Cap".

Jan 1, 1987

By Klinefelter G

The United States Steel Mining Co., Inc. recently experienced a major mine fire at the Cumberland Mine. This mine is located in Greene County, Pennsylvania, U.S.A. and is mining a high volatile bituminous coal seam (Pittsburgh Seam). The mine fire was success- fully controlled and extinguished without loss of life or serious injury to any miner or mine rescue personnel and finally reopened within 40 days of its inception.

Jan 1, 1988

Before the arrival of the first Europeans, Aborigines living in the northern Flinders Ranges mined ochre - an earthy form of haematite used for pigment.The discovery of copper ore at Kapunda and Burra in the 1840s stimulated the early settlers to prospect further north along the ranges. Many of the new discoveries were not properly evaluated and companies were floated on the most tenuous evidence.

Jan 1, 1993

The Metallurgical processes used in the gold industry in Queensland since the 1850's are reviewed. The major upswing in, gold processing this decade has brought the technology of heap leaching, carbon in pulp and carbon in leach, flotation for gold and tailings retreatment to Queensland. In many cases operators have developed or improved these processes to treat difficult ores or to cope with local climatic conditions.

Jan 1, 1989

A paper presenting the results of studies carried out on rotary drill bit life at EluraMine N.S.W.Contributing parameters, including dataon drill operation and geology are compared to the performance observed for the drill bits. Correlation and performance characteristics are presented, relating this data to cutting size distribution over drilling depth.Details are presented of experiencegained through the operation of rotary drillsat Elura.

Jan 1, 1985

SOME notes on the works of the Electrolytic Refining and Smelting Company of Australia will no doubt be of interest to members of the Institute, more especially as much of the work is new to Australasia.As many of the members who may read this paper have not been in a position to visit works of this kind, and are consequently not thoroughly acquainted with all the operations carried on, the author has taken the liberty, in some cases, to enter into explanation which would otherwise be unnecessary.The works are situated at Port Kembla (New SouthWales), about fifty miles south of Sydney, and are approachable both by rail and water. The Government has recently built a low-level jetty upwards of five hundred feet long, and intends installing at an early date an electrically operated portable crane to facilitate the handling of material to and from the boats. Thi.s will mean a considerable reduction in the length of time that boats are laid up at the jetty. There are also under construction two breakwaters, which, when complete, will materially assist shipping operations. The works as they exist are capable of turning out 1200 long tons of refined copper per month. It is gratifying here to note the unqualified success with whichthe E.S.A. refined copper met with on first being put on the market.

Jan 1, 1911

By S T. L Harrison, J-P Franzidis, M Becker, N Dyantyi, J L. Broadhurst

Gold mining is a major contributor to the South African economy, but is associated with several environmental issues such as acid rock drainage (ARD). ARD is due to the oxidation of sulfides in gold tailings and is characterised by low pH, high sulfate content and elevated concentrations of heavy metals that contaminates scarce water resources and subsequently limits the use of such waters without treatment. Treatment strategies can only be implemented if the acid-generating potential of mine wastes is effectively predicted using common static and kinetic acid prediction tests. The choice of test performed is usually a trade-off between the number of samples, speed of the test, cost of the analysis and level of information obtained. Often the results of these various tests are not consistent with one another. This study uses mineralogy to analyse biokinetic test results of a Witwatersrand gold sample in order to improve the understanding of behaviour of mine wastes under different ARD prediction test conditions.All ARD prediction testing methods investigated in this study showed that the gold sample is considered to be potentially acid forming with net acid generation (NAG) pH of 2.5 and net acid producing potential (NAPP) of 36 kg H2SO4/t. Results of biokinetic test showed that ANC was consumed within four days confirming acid producing potential of the sample with low neutralising potential as observed from acid base accounting (ABA) (4.7 kg H2SO4/t) and mineralogy (4.9 kg H2SO4/t). Results generated in this study demonstrated importance of mineralogy in both understanding the controlling reaction mechanisms playing key role in ARD formation and its capability as a prediction technique. Future work will focus on the application of mineralogy in interpreting the behaviour of mine waste under different static test conditions with a view to assessing their applicability and reliability in estimating potential acid generating characteristics of gold tailings.CITATION:Dyantyi, N, Becker, M, Broadhurst, J L, Harrison, S T L and Franzidis, J-P, 2013. Use of mineralogy to interpret laboratory-scale acid rock drainage prediction tests - a gold case study, in Proceedings World Gold 2013, pp 519-526 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 26, 2013

Although the flotation cell has been under continuous development over the past 80 years, an understanding of the precise roles of a cell in produc- ing the flotation result had evolved slowly. In fact, detailed studies of cell dynamics began only in the 1940s when flotation practice had almost reached the half-century mark. The earliest generalizations related cell capacity to power intensity (hp/vol- ume) (Rose, 1946), and specific operating features such as aeration and power ' consumption to impeller submergence and operating speed (Read, 1933). In the 1950s hydrodynamic characterization of cells through power coefficients and air flow numbers began (Arbiter and Harris, 1961) and has continued to the present, with increasing industrial use of these concepts (Degner, 1982; Degner and Treweek, 1976). Liquid flow measurements in Wemco cells (Degner, 1982) made liquid flow numbers and turnover frequencies available for more complete under- standing of cell dynamics. The present overview of flotation technology is a critique of cell design. The cell process represents the interactions between cell dynam- ics, cell geometry, and ores, with the latter prepared for that interaction through size reduction and reagent treatment. While previous invest- igations of flotation cells have accepted all cell designs uncrit- ically, the present study considers the physical process components that an effective cell must provide, and then compares a limited number of

Jan 1, 1984

By Grieveson P, Terry B. S

Carbothermic reduction of sulphide minerals for achieving a selective separation of metallic species from complex minerals has been discussed by considering the prevailing oxygen potential during the course of reaction. Construction of univariant plots for the reduction of sulphides with carbon monoxide gas or carbon and in the presence of either lime or anhydrous calcium sulphate is the key feature of this work. The theoretical calculations for univariants in the Cu-Fe-S-O system indicated a preferential separation of metallic copper and iron by imposing a chemical potential. This is evident from a logarithmic plot of sulphur dioxide partial pressure against reciprocal temperature. The results are compared with empirical data for the reduction equilibrium. The reduction behaviour of the constituent sulphides are also discussed together with the experimental results and theoretically predicted phase stability diagrams.

Jan 1, 1992

By Pell D

Mechanical cleaning of coal was porforined in a few small plants in New South Wales from 1577 brit the first large coal washeries were built by Broken Hill Wbprietary Company Limited and Australian Iron and Steel Pty. Limited in the late 1940's. Mechanization of colleries in the 1950bs was abcomp" anied by construction of many coal washing plants and in the 1960's the growth of the coal export trade gave further impetus to the coal preparation industry. Design of coal preparation plants in Australia is modelled on practice overseas. Planning of a new plant in- volves investigation of many factors both technical and economic and the preparation of a specification by the operator for the designer's guidance. A wide range of preparation processes and equipment is on offer, but the nature of the coal to be treated and the separating efficiency desired usually dictate process selection. Simple or moderately difficult separation can be achieved with jigs, shaking tables or water washing cyclones. Coal which is difficult to treat or which has to be cut at a specific gravity lower than 1.5 is normally washed in a heavy medium process. In large plants it is usual to separate the coal into large, small and fine fractions and concentrate each fraction in a circuit designed to suit the grain size handled.

Jan 1, 1969

By T. Baker

The Eloise Cu-Au deposit is 60 km SE of Cloncurry in NW Queensland and has a current indicated reserve of 3.2 Mt @ 5.8 per cent Cu, 1.5gA Au and I9g/t Ag. It is hosted by metasediments and metabasic rocks that underwent amphibolite facies metamorphism at 550-600¦C and less than 3.5 kb. Peak metamorphism coincided with the regional D2 event which produced an S2 foliation with north-south strike and variable sub-vertical to steep east or west dip. The deposit is associated with several major shear zones parallel to the S2 foliation. The lodes form part of a large alteration system that is localised by the retrograde shear zones. Homblende-biotite-quartz with minor sulphides occur early in the alteration paragenesis which is overprinted by chlorite-muscovite-pyrrhotite-chalcopyrite ¦calcite+¦nagnetite. The later assemblage replaces the earlier Fe-K alteration as well as Fe-rich metamorphic assemblages such as homblende, biotite and staurolite indicating a post peak metamorphism timing for ore formation. Although replacive textures are the most common, the alteration can display open space infill and brecciation as well as durchbewegung and mylonite textures indicating that mineralisation occurred during ongoing ductile deformation. All these features are crosscut by a later brittle phase of calcite-chlorite-quartz¦pyrite alteration.

Jan 1, 1994

By M Spagnolo, M Ashley, D, L Reemeyer

PasmincoÆs Century Concentrator in North West Queensland commenced operations in November 1999. The nameplate production capacity of 500 000 tpa of zinc metal production in concentrate was achieved in August 2002. Completion of the production ramp up was successful due to the culmination of a number of initiatives throughout 2001 and 2002. Mine to mill interaction to understand and eliminate head grade related bottlenecks affecting Concentrator production and reduce feed variation. Grinding circuit process development û operating and process control strategies to improve stability and reduce grind size to support zinc recovery. Pumping upgrades to control spillage in ultrafine zinc flotation Low density zinc flotation strategy û to improve silica-sphalerite separation to improve zinc recovery while maintaining acceptable silica in final concentrate. Flotation circuit process development û froth crowders, froth cameras and reagent control strategies to improve primary zinc flotation performance. Review and implementation of longer campaigns between planned shutdowns to improve availability. Team reorganisation û to improve setting and implementation of metallurgical strategies. This paper describes these initiatives and their contribution in achieving the production target. It also notes the ball mill motor failures that delayed the successful achievement of the ramp up, and CenturyÆs response to minimise the production impact. The paper also outlines the capital improvement program that was implemented to improve zinc recovery to design 82.5 per cent recovery once the production rate had been achieved.

Jan 1, 2003

By Ross T. J

Renison Limited operates an underground tin mine employing both cut and fill and open stope methods, at Renison Bell on the west coast of Tasmania. Mining in the region commenced in the 1890's. Development of the current mining operation commenced in 1965. The ventilation system used at Renison in its present configuration is a function of current mining methods, orebody characteristics and prevailing Tasmanian Department of Mines Inspection Regulations.

Jan 1, 1988

By Noller B. N, McGill R. A

The Alligator Rivers Region has been the scene of one of Australia's most intensive environmental monitoring efforts since the current generation of uranium mining was mooted in the 1970s. Prior to mining, the local environment and the nature of potential impacts were not well known. The initial monitoring programs therefore included large baseline characterisation and research components. After some 15 years, water, soil and sediment monitoring programs have been reduced to a fraction of their early size, as the mining and natural systems became better known and characterised, and the actual nature of the environmental impacts were established. Modem techniques allow much more rapid and thorough identification of chemical species and elements of concern, allowing much more focused monitoring programs to be designed. In the 1980s data collection was emphasised at the expense of interpretation, and monitoring programs were maintained at much higher levels than were in fact required. It is now clear that investigations are important and should be distinguished from monitoring programs, and that the timely interpretation of investigations and implementation of recommendations can greatly reduce the effort and expense that can be involved in a monitoring program. Monitoring programs based on a sound understanding of potential environmental impact may then be efficient and cost-effective, yet provide sufficient information to assess the environmental impact of mining, guide further environmental protection measures when problems are detected, and demonstrate compliance with regulatory requirements.

Jan 1, 1994

By S Gray

Based on the 2021 Volume 5 State of PlayTM mining survey of key executives and board members in the mining sector, the key responses to ‘Which of the following technologies will have the biggest impact on mining in the next 15 years?’, were ‘Sensing and Data’ followed by ‘AI and Analytics’. From the early 1970s it would have been unlikely to predict the level of sensing and automation introduced to the broad industrial sector. No better example is the automobile industry where the combination of technological advances and external drivers (such as emissions control) have driven an incredible rate of change. The introduction of sensing, data, AI, and automation in the mining industry is just ramping up. Until now our energy efficiency, environmental footprint, labour shortage, skills, and safety have not been challenged by stakeholders in the way we are seeing market forces develop today. In order to address these challenges, we need to look back to the automobile industry and learn their lessons to accelerate our application of digital capability, analysis, AI and automation This is critical, particularly as access to skilled human resources becomes more difficult. An example of how this can be achieved in a gold processing plant utilising the latest real-time sensing technologies is the ‘Carbon Scout’ developed by Curtin University, and OLGA developed by CSIRO, which are both online technologies, coupled together with Gekko’s ‘Neon’ digital platform to achieve a fully automated real-time gold processing system.

Aug 24, 2022