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We all live in professional silos û comfort zones, where we talk to like-minded people with the same training, experience and view of the world. We note in passing the existence of other disciplines, but they are tolerated rather than embraced. To the geologist, the metallurgist is a mad scientist conjuring gold out of some foul solution about which the less said the better. To the metallurgist, the geologist is a bearded, self-appointed sage who guesses what is under our feet by sniffing the air, and drives a Land Rover badly. As to the view of mining engineers held by both geologists and metallurgists, this is best left to the imagination. And of course we are all confused by the term æmetallurgistÆ. I am called a metallurgist though my skills are in mineral processing not metal processing, but I canÆt be called a mineralogist because that definition is already taken. *Please note that this is available as an extended abstract only*

Jan 1, 2005

By Crawford M

During the initial development of Mount Isa Mines power was supplied from a temporary power plant situated near the Man & Supply Shaft. The main power plant was placed in service early in 1931 and then comprised two Babcock and Willcox boilers, fired by pulverised fuel, and two British General Electric Company's turbo-alternators of 5,000 kW. each. Both plants have been described by A. F. McAskill in the Journal of the Institution of Engineers, Australia.From 1931 power demand progressively increased due to greater production, further mine development in the harder sulphides increased pumping for mine drainage and additions to mill and smelter until, by 1935, the plant was inadequate for further output commensurate with a reasonable safety margin.Coincident with the added power demand, operating conditions involved a fuel problem which could not have been anticipated. The ash content of the fuel supplied gradually increased from 13% to 16-5%, while the melting point of the ash decreased with higher pyrite content.Temperature conditions in the furnace required careful control to cope with ash formation and slag accretions.Consequently brickwork, excessively stressed on water walls, was constantly under repair, and required suspension periods of 50% of operating time for cleaning and overhaul.Load conditions varied continually, therefore the high heat liberations in the furnace, necessary to accommodate peaks in fluctuating output, resulted in ash fusion.

Jan 1, 1939

At the beginning of the seventies pre- drainage of methane was introduced in West German coal mining in order to reduce the gas emission from the worked seam. After three pilot tests on the "Rheinland" Colliery (86 boreholes in seam "Prasident"), "Bergmannsgluck/ Westerholt" Colliery (23 boreholes in seam "Gustav") and "General Blumenthal" Colliery (27 boreholes in seam "Hugo" and 170 boreholes in seam "Karl") systematic large scale tests with extended investigations were carried out un the "Rheinland" Colliery (127 boreholes in the seams "Anna", "Blucher", Prasident"). During this time an analogous test was carried out on the "Consolidation" Colliery (21 bore- holes in seam "B"). In these studies and tests the technical feasibility, efficiency and economy could be proved, so that pre-drainage of methane starts spreading. On the "Rheinland" Colliery pre-drainage has become common practice in gassy seams. Mainly two points impede a faster spreading of method: 1. in many cases the necessary requirement, that one or both of the gate roads should ire driven 6 to 12 months before the face is worked, is missing. This is mainly due to the difficulty of retreat mining in passe seams.

Jan 1, 1982

By G Hancock, J Lowry, T Coulthard, W Erskine, M Saynor

An important part of planning for the rehabilitation of uranium mine sites is the ability to assess the geomorphic stability of the final landform, over time frames ranging from decades to millenia. Depending on the environmental conditions, erosion features such as gullies may incise into containment structures, potentially leading to the exposure and transport of encapsulated radioactive material. Further, erosion may lead to increased sediment loads and the transport of other mine-related contaminants off-site and into downstream waterways. While erosion may be monitored and assessed over the short term (years to decades), the longer-term behaviour (centuries to millennia) of such landscapes is not within any meaningful human management time frame. Landscape evolution models (LEMs) can provide information on soil erosion rates at decadal or centennial scales over large spatial scales, and evaluate the sensitivity of these processes to environmental changes. However, an important issue associated with the use of models is the ability to assess the reliability and accuracy of the model. In this paper, the CAESAR-Lisflood LEM is tested for its ability to predict soil erosion from a series of 30 m × 30 m experimental plots specifically constructed for this purpose on a trial rehabilitated landform at the Ranger Uranium Mine in the Northern Territory, Australia. Model predictions of bedload and suspended sediment loads from the erosion plots were compared with field measured observations collected over four wet seasons from the trial landform. Once calibrated for the specific site hydrological conditions, the predicted sediment yield – specifically, bedload – demonstrated an excellent correspondence with the field data. However, longer-term simulations of ten years identified an exhaustion effect in sediment yield from the landform. These latter results indicate that a weathering function needs to be incorporated into CAESAR-Lisflood to ensure confidence that the CAESAR-Lisflood LEM will be able to correctly predict the long-term evolution of a rehabilitated landform once it has been?constructed.CITATION:Lowry, J,?Saynor, M,?Erskine, W, Coulthard, T and Hancock, G, 2014. A multi-year assessment of landform evolution model predictions for a trial rehabilitated landform, in Proceedings Life-of-Mine 2014 , pp 67–80 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

WaihiÆs Cornish Pumphouse is located on the edge of town in a dynamic and changeable area where history affects the future. As in any successful project, ingenuity and team work have been significant factors in the planning and implementation of the buildingÆs relocation.   Work around the Pumphouse site commenced circa 1900 with preparation to sink the No 5 shaft. Construction of the pumphouse and the steam driven C pump was completed by 1904 with hints of what was to come evident in 1905 as the No5 Shaft collar had sunk 350mm in four years. By 1907 surface cracking developed over the Milking Cow cave area and in 1913 200 mm was cut off the main pumping rod as the ground was sinking at a rate of 25 mm per year.   In 1913 ground around No 6 shaft had subsided 600 mm.It was also the end of an era as steam gave way to hydroelectricity and electric pumps replaced the C Pump. C Pump was maintained as a backup from 1913 to 1929 and then finally scrapped. 25 years of underground caving operations removed approximately 400 000 cubic metres of ore leaving a 7 ha collapse crater that eventually became known as the mine lake.   On the edge of town a tension zone over the Royal Lode began to develop 50 m diameter chimney collapses as large scale blocks relaxed into unfilled stopes in the old Martha underground mine. After the 1999 collapse part of the main street was closed and after the 2001 collapse Hazard Zones were declared, more streets closed and areas evacuated and retired from residential use.   By 1984 the Pumphouse has approximately one degree of tilt and in 2002 tilt on the Pumphouse accelerated briefly and then settled down. Tilt accelerated again late in 2004 and a scoping study was initiated to define protection options for the pumphouse. The Martha Mining Licence requires Newmont to 'Take whatever precautions are necessary to protect the old Cornish Pumphouse adjacent to No5 shaft' and viable solutions needed to found.   Any work on the Pumphouse comes standard with a wide range of stakeholders, governing agencies and legal framework to consider. Land Information New Zealand (LINZ) is owner and administrator of the pumphouse.

Jan 1, 2006

By J M. Galvin

History attests to the catastrophic consequences that fire, explosion and contaminated, noxious andirrespirable atmospheres can have for workplace health and safety in underground coal mining. It also confirms that fires and explosions present the greatest risk of partial or total loss of underground mines and equipment and that this risk continues to materialise. The design, implementation, operation and maintenance of the mine ventilation system are core controls for managing the hazards associated with these risks, both for preventing them from materialising and for mitigating their consequences if they do materialise. These are most effective when embedded in a risk management approach.

Oct 12, 2022

Zinc sulphide concentrate from Mount lsa, Australia, was leached in acidic sulphate-chloride solutions using ferric ions as oxidants under atmospheric pressure. The parameters of temperature, particle size and concentrations of ferric and chloride ions were evaluated.The shrinking core model can be used to describe the leaching which is limited by the electrochemical processes in the initial leaching stage, and by both surface reaction and pore diffusion processes subsequently. The apparent activation energy measured in the initial leaching stage is 49 kJ/mole over the temperature range 60 to 90°C.About 99 per cent of the contained zinc in the -45+38 µm particle sample dissolved at 90°C in a 0.5 M H2SO4/0.1 M Fe2(SO4)3/0.8 M NaCI solution within two hours. Some nine per cent of sulphide sulphur was oxidised through to sulphate; the remainder was convened to elemental sulphur.The mixed sulphate-chloride system has advantages over separate chloride and sulphate systems due to the low reagent cost, high leaching rate and possible selective leaching of zinc sulphide concentrate with high lead contents.

Jan 1, 1994

By Z Li, J Pan, D Zhu, W Zhou

In order to enhance the roasting behaviours and metallurgical properties of hematite pellets, which have the problems of high roasting temperature and low compressive strength, a process of producing Brazilian hematite pellets by adding high sulfur magnetite was developed in this paper, and process parameters have been optimised. It is shown that the roasting temperature decreases from 1320¦C to 1200¦C by adding 30 per cent of high sulfur magnetite. New Fe2O3 crystal oxidised from Fe3O4 is more active, which is beneficial to induration of pellet. When the ratio of magnetite increased to 50 per cent, only about 90¦C of the roasting temperature was decreased. Higher ratio of high sulfur magnetite causes more porosity of pellets because of oxidative desulfurisation, which is harmful to the strength of roasted pellets. The reduction disintegration index (RDI), presently RDI+3.15 of product pellets is aggrandised from 87.79 per cent to 99.54 per cent and 97.55 per cent, and the reduction swelling index (RSI) is lowered from 36.25 per cent to 12.50 per cent and 6.25 per cent respectively, by adding 30 per cent and 50 per cent of high sulfur magnetite. The compressive strength of roasted pellets is elevated obviously by adding high sulfur magnetite, which resists the inner stress of pellets during reduction process, so as to enhance the RDI and reduce the RSI of product pellets. In addition, the inner porosity may be filled by the swelling during the reduction process, which can also lower the RSI. The process provides a low power consumption of making hematite pellets that high sulfur magnetite can decrease roasting temperature significantly and improve the metallurgical properties of hematite pellets dramatically.CITATION:Zhu, D, Zhou, W, Pan, J and Li, Z, 2013. Study on improving roasting behaviours and metallurgical properties of Brazilian hematite pellets by adding magnetite with high sulfur content, in Proceedings Iron Ore 2013 , pp 525-530 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

By L Basnayaka, N Subasinghe, B Albijanic

"It has been recognised that the presence of clay minerals in ores adversely affect flotation performance. In this study, changes in rheological properties of the flotation pulps under normal operating conditions were studied with additions of bentonite and kaolinite clays at various concentrations. Zeta potential measurements were also carried out to determine the changes in surface charge due to adsorption of clay particles. The results showed that bentonite clay adversely affects floatability of pyrite while kaolinite clay had a lesser influence on flotation of pyrite. The addition of Ca2+ ions to the pulp containing bentonite modified the rheological characteristics and in turn improved the pyrite flotation. It was also observed Ca2+ ions suppressed the swelling properties of bentonite and altered surface charge properties of bentonite clay particles. It has been shown that the flow index affected the ultimate recovery and it may provide a means to monitor flotation performance in routine plant operations.Citation:Basnayaka, L, Subasinghe, N and Albijanic, B, 2016. Effect of Clay Rheology on Flotation of a Refractory Gold Ore, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 77–84 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

By Y Wei, H-B Mnhlhaus

Particles are by far the easiest objects to simulate, because their dynamics is simple. Determining the motion of particles and their interaction, a wide variety of deformable structures can be constructed by connecting particles that have mass, position, and velocity, and that respond to forces. Starting from this simple idea we have derived what we call the particle-lattice method for the solutions of boundary value problems of deformation and fracture of solid mass. The problem of rock breaking by blasting operations as well as fracture and flow of rocks fragments involve momentum transfer between solid and fluid; gas flow and reactive mass transfer. In this paper we outline the method and describe briefly the salient features of the algorithm. We derive relationships between the contact properties for the discrete model and the properties of the underlying continuum and fluid flow coupling procedure. Finally we illustrate the potential of the method by means of example solutions related to the dynamic fracture and flow in jointed rock by blasting.

Jan 1, 1999

By Jagger ND

Pressure filters were found to be necessary to produce Elura silver/lead and zinc concentrates at sufficiently low moisture contents for bulk cargo shipment by sea to smelters.The difficulty in obtaining low moistures was due to the fine primary grind, 80% passing 45 microns, and resultant fine concentrates, 97% passing 45 microns.The filtration system was designed to filter up to 90,000 tonnes/year silver/lead concentrates and up to 130,000 tonnes/year zinc concentrates.This paper details the preliminary test work to select Larox automatic pressure filters, and the commissioning and operation of these filters to achieve design criteria for both concentrates. The design criteria for both concentrates have been bettered due to the concentrates being coarser than the design sizing.

Jan 1, 1985

By P Elliott, D Pershke

In a minerals processing context, sustainability is about using natural resources more efficiently to achieve maximum economic benefits with minimal environmental impacts. It embodies five overarching themes, which the paper will illustrate with practical examples from Australian minerals processing plants. These are:resource utilisation and materials efficiency,process waste reduction and enhancement of co-product values,reduction of water use and impacts,reduction of energy requirements and greenhouse gas emissions, andenhanced control of minor elements and toxic materials. Sustainability could be embedded profitably in minerals plant design in three dimensions: 1.technology,2.design, and3.operations. This presentation discusses a set of principles that could be applied to minerals processing technologies and provides an outline of sustainability assessment and opportunities evaluation tools. The application of the tools is illustrated through a case study by analysing a suite of nickel processing technology routes. The analysis reveals that current generation of nickel processing technologies do possess real potential to emerge as sustainability champions in integrated processing of nickel ores and concentrates, if they are designed, engineered, and operated for sustainability and adapted effectively to site specific constraints and opportunities. The paper will address data gaps and uncertainties regarding the impact of scaling up of pilot-plant performance, and provides strategies to overcome them.

Jan 1, 2006

This paper provides a brief fundamental insight regarding the fabric media concept for liquor filtration. The subject matter will be of interest to metallurgists and engineers with professional responsibility for world class design of solid liquid separation processes and efficient lowest cost operation of existing mineral process plant. Avocet Mining commissioned the worldÆs first mineral liquor clarification process incorporating a fabric media liquor filter at their Lanut gold mine in Sulawesi, in 2004 with design consulting provided by the Australian company SLS Technology Pty Ltd. Development of the technology continues with applied research focused on selecting textile parameters to apply filtration to a wider range of particle and contaminant types, higher solids concentrations, and different process liquors. Liquor filtration with the Fabric Media technology offers an array of attractive benefits. For Avocet Mining, filtration of pregnant liquor directly from the heap leach pad has enabled removal of the sediment pond and sand filters from the traditional process flow sheet, thus providing significant cost and installation time savings. Avocet Mining has recently expressed confidence in the technology indicating selection preference of the technology for the expansion at Lanut and for a new project. The application design window for the Fabric Media concept is extremely flexible with the technology now successfully applied to many different liquor chemistries and application objectives around the world. Potential cost savings for solid liquid separation process plant, such as counter current decantation circuits, clarifier vessels and thickener tanks can be calculated from laboratory measurements or pilot plant demonstrations.

Jan 1, 2008

By M Dunglison, P M. Cameron

Simultaneous mass-balancing of a mineral processing flow sheet results in adjustments to each data point that reflects the accuracy and precision across the full set of data. In this way, all the good work that goes into designing the sampling and analysis protocol for each sample point is leveraged in order to produce a æbetterÆ set of balanced numbers for every sample point in the circuit. Few operating plants employ whole of circuit balancing techniques to produce reported operating results. This situation is changing with the application of mass balancing technology which utilises redundant data for production accounting and metal reconciliation from product to ore source across multiple phases and multiple time periods. Mine and plant data can now generate credible information to improve productivity. Mine and plant personnel can now use consistent data sets for review and planning. Decisions based on balanced data can be made quicker and with increased confidence.

Jan 1, 2005

The Australian Constitution specifies certain powers of the Commonwealth Government to be used in its capacity as the national government. Certain of these broad powers result in the Com- monwealth having a facility to play an important part in the development of the mining industry. The State Governments, however, by virtue of their wide powers to regulate matters within the boundaries of a particular State, are more directly involved in the day to day administration and standards of activities of mining operations. In this respect the Common- wealth has something of a dual role because of its "State-like" responsibilities for the mainland Terri- tories. The components of the role that the Common- wealth Government discharges in relation to the mining industry are qualified to varying extents at particular times by the political persuasion of the Government. In absolute terms the components are as follows. 1. Economic management. The Commonwealth's fiscal and monetary policies have an important effect on industry as well as on State finances. In particular, the taxation regime employed by the Commonwealth Government is of direct importance to economic decision-makers in the mining industry. 2. International matters. International trade and commodity matters are, more and more, becoming an everyday part of the conduct of a nation's foreign affairs. 3. Exports. The Commonwealth Government, via the constitutional powers over overseas trade, have exercised varying degrees of control over mineral exports to achieve particular objectives. 4. Foreign capital and investment. Australia in general, and the mining industry in particular, is and will continue to be a net importer of capital. There appears to be bipartisan political agreement in Australia that foreign investment policy must be enunciated to ensure that investors. are in no doubt that Australia welcomes beneficial investment and technology from overseas. 5. Environment and Aborigines. Governments, both Commonwealth and State, have in recent years become more involved in these areas in response to their interpretations of community aspirations. 6. Energy. Access to assured supplies of energy is now viewed, by Governments worldwide, as a desirable asset to ensure the well-being of a nation's people and industries.

Jan 1, 1978

By M Zanin, E Chan, D Xu

An experimental design has been developed to investigate the relative influence of distinct pulp and environmental properties on froth stability in the flotation of a typical porphyry copper ore. In particular, factors such as frother and collector type, feed particle size (P80), solids per cent, composition (chalcopyrite and pyrite content), as well as grinding environment (mild steel versus stainless steel, high and low pH) have been varied in a controlled manner, and the resulting froth stability evaluated. A previously developed froth stability column, based on the Bikerman approach, was used to measure the froth height and half-life in each test. The relative effect of each factor is presented here on a comparative basis. It is shown that frother type is the most important factor, with marked difference in froth stability when switching from methyl isobutyl carbinol (MIBC) to glycol based frothers. Solids per cent and particle size also play a significant role. The grinding environment had lesser effect on the resulting froth stability, although mild steel grinding gave higher froth stability compared to stainless steel grinding. The experimental evidence supports the hypothesis that in porphyry copper flotation the grinding environment influences surfaces oxidation, pyrite activation and the extent of hydrophobic particles reporting to the froth phase. This has an indirect effect on the resulting froth stability, which is however small if compared to the other factors. This work is still in progress, and extension to other mineral systems is planned. However, some insights are offered to operators on the parameters which are more likely to have an impact on froth stability in copper flotation plants.CITATION:Zanin, M, Chan, E and Xu, D, 2014. Empirical evaluation of factors affecting froth stability in copper flotation, in Proceedings 12th AusIMM Mill Operators’ Conference 2014 , pp 193–200 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 1, 2014

The high-shear colloidal mixer is generally recognised as the most efficient method of mixing cement based grouts. Only recently however has this technology been applied to the production of cemented rockfill (CRF) for use in underground mines in North America. Traditionally, paddle type mixers have been used to produce the cement based slurries required for the preparation of CRF. While considerable success has been achieved with these mixers, tremendous advantages are attained with the colloidal mixer. The combined effect of the highly efficient mixing action and the ability to mix low water/solids ratios, allows for reductions in the cement content for a given strength requirement. Cement can also be replaced by cheaper fillers such as flyash, resulting in further cost savings. Although large-scale dedicated CRF batching plants are typical, there is a growing need for mobile plants capable of operating anywhere underground. The compact size and rapid batching speed of high-shear colloidal mixers has allowed them to be incorporated into skid mounted systems capable of producing and discharging cement based slurries onto rockfill aggregate for the production of CRF. In many cases run-of-mine development waste can be used as CRF aggregate with these slurry plants thereby reducing the cost of waste rock removal. These relatively low cost portable plants have now allowed several mines to economically recover isolated pillars and realise positive returns on their investment.

Jan 1, 1998

By D J. Bradshaw, E M. Wightman, B Newcombe

Flash flotation plays an integral role in many of the gold and sulfide mineral concentrators around the world, and yet despite this widespread use, very little information on this unit process is available in the published literature. For operations to maximise the performance of their flash flotation circuits, understanding how these cells operate, the nature of the particles they target and how to predict whether a flash flotation cell should be used on a specific ore type is of vital importance. This paper provides a summary of the key findings of a large flash flotation research project based in the operating environment of a refractory gold concentrator. The influence of key flotation performance criteria including gas dispersion, residence time and particle segregation within the cell will be discussed and recommendations for process improvements will be made throughout. The nature of the particles within the flash cell will be examined, as will the impact on the type of particles that are passed to downstream processes when the flash flotation cell is taken off-line. The development of a laboratory method to determine whether an ore is suitable to undergo the flash flotation process is also presented for its potential to aid in flow sheet development and optimisation for new ores.CITATION:Newcombe, B, Bradshaw, D J and Wightman, E M, 2012. Into the belly of the flash à Insights into the mechanisms at work within a flash flotation cell, in Proceedings 11th AusIMM Mill OperatorsÆ Conference, pp 163-170 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 29, 2012

The Que River and Hellyer polymetallic massive sulphide ore bodies are located 3 kilometres apart in the Cambrian Mount Read volcanics of Western Tasmania. Both deposits are classic examples of the Kuroko volcanogenic style. Base and precious metal rich hydrothermal solutions rose through a deep fracture system and vented on the sea floor, causing sulphides to accumu- late in adjacent topographic lows. Together the preproduction geological resource is approximately 23 million tonnes at greater than 18% zinc plus lead, with economically significant silver and gold. Exploration by Aberfoyle in the Mount Read volcanics com- menced in 1970. Que River was discovered in 1973 following a comprehensive data review, a regional stream geochemical survey and a helicopter-borne electromagnetic survey. Production began in 1981, and the mine is currently producing 300,000 tonnes per year. The ore is sold to the Electrolytic Zinc Company of Aus- tralasia Ltd mill at Rosebery. Ten years of extensive geological mapping, soil geochemistry, and induced polarisation, combined with continual study of the Que River orebody and its host rocks, formed a strong frame- work for the discovery of the Hellyer deposit, which was found as a result of drilling .a subtle time domain electromagnetic anomaly in 1983. Hellyer is currently being mined at a rate of 250,000 tonnes per year, with the ore being concentrated at Aber- foyle's converted Cleveland tin mill. Treatment of 1 million tonnes per year will begin in early 1989 at a new mill located near the Hellyer site.

Jan 1, 1988

By J Johansson

The aim of this paper is to discuss how to form work and organisations in the mines of the future. The Kiruna underground iron ore mine in the far north of Sweden is used as an example on how technical development affects organisational issues like skills, work identity and gender. Over a period of 50 years one can see a transformation of work from manual underground work to automation and remote control from surface level. What characterised the old underground workface was the close relation between man and the hard rock and with arduous physical work under dangerous conditions. Today, the face miners are located on the seventh level of an office building close to the mine. There is also an emerging, and in many aspects already evident, knowledge transformation û from the old and obsolete physical and tacit knowledge and skills (for example the ability to æread the rockÆ) to something new, which can be described as abstract æhigh-techÆ knowledge and skills. The modern technology has created a new type of work û new in terms of competencies and knowledge as well as workload and organisation. At the same time the mining company are recruiting more women and promoting the former pure male work as attractive workplaces for both women and men. All this has effects on how individuals and company create and recreate skills, identity and gender. To some extent the technological development predestines these changes, but there are some choices to be done when forming good work and organisations for the mines of the future. The traditional mining workplace culture and behaviours and the old type of masculinity, the æmachoÆ style, will be challenged by the new æhigh-techÆ work and new competency demands. The changes risk meeting restoring responses, which can have negative impact on the performance of the organisation, for example making it inflexible and perhaps ælaggingÆ behind the technological development. These questions need to be handled when planning future mining.

Jan 1, 2008