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By A Golev, G Corder

The concept of the circular economy has been gaining traction both in Europe and China.In Europe the Ellen Macarthur Foundation see their mission as accelerating the transition from a linear take-make-dispose economic model to a circular model that is restorative and regenerative by design, and aims to keep products, components and materials at their highest utility and value at all times. The Chinese Circular Economy initiative is effectively a sustainable consumption and production program utilising cleaner production, industrial ecology and life cycle management approaches to meet the national challenges of maintaining rapid economic growth while simultaneously enhancing environmental quality and maintaining social progress. A key characteristic of both of these circular economy initiatives is to design out, reuse or minimise the generation of waste.The mining sector, by definition, is represented by linear rather than circular activities, by supplying resources to society. However, being one of the world’s largest waste generators, the sector can adopt similar logic to that of the circular economy to improve its sustainability performance. Waste is a critical issue along the whole metals value chain, from mining waste to eventual end-of-life products, such as scrap steel from construction and demolition waste or the growing problem of electronic waste.CITATION:Corder, G and Golev, A, 2016. Can mining be part of the circular economy or is it squaring the circle?, in Proceedings Life-of-Mine 2016 Conference , pp 121–123 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By A Riles

"Three issues of relevance in a modern tailings storage facility (TSF) are:geotechnical stabilitymanaging acid rock drainage (ARD) from pyritic tailingsmanaging the tailings from cyanidation of gold ores. Drawing on examples from both copper porphyry flotation and sulfide-hosted gold ores, this paper demonstrates that giving some weight and importance to the process tails properties upfront can influence the flow sheet and not only improve tailings management effectiveness but also impact positively on economics. In the case of a typical copper porphyry ore with moderate pyrite content, the rougher tail in a conventional high pH selective flotation step is usually classified as potentially acid generating (PAG). To avoid the generation of ARD within the tailings and the requirement for a costly plastic lining, subaqueous deposition is recommended, which in turn has negative implications for tailings stability, consolidation and closure. Adopting a neutral pH rougher stage rejects silicate gangue but recovers pyritic material to the cleaners for a subsequent selective flotation stage, often after regrinding. This effectively quarantines the PAG pyritic material in a much lower volume cleaner tail, which can then be appropriately encapsulated within a larger non-lined flotation tails facility. It also facilitates cyanide leaching of the cleaner tail for gold recovery, with the encapsulated tailings facility being suitable for cyanidation tails storage. A case study from Europe is examined. For gold ores where the gold is sulfide-hosted, but not refractory, a flotation route with cyanidation of the concentrate can similarly produce the majority of tailings as a benign flotation tail and again quarantine the low volume concentrate leach tail in a small encapsulated cell with appropriate residual cyanide management measures applied. Overall economics for intensive leaching of a low volume concentrate stream can also be surprisingly positive. A feasibility study design example of the process and TSF is presented. CITATION: Riles, A, 2016. An Integrated Approach to Optimising All Concentrator Products, Including Tailings, in Proceedings The Third AusIMM International Geometallurgy Conference (GeoMet) 2016, pp 341–346 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jun 15, 2016

Mining companies around the world devote considerable effort to production reconciliation and metallurgical accounting. However, although sampling, weighing and analysis methods used to obtain the raw data for metal balancing continue to improve, they are still areas that are sadly neglected. Using the latest metallurgical accounting package to improve metal balancing is fundamentally flawed if the data used are unreliable in the first place. The basic rule for correct sampling is that all parts of the material being sampled must have an equal probability of being collected and becoming part of the final sample for analysis. If this rule is not respected, sampling bias can easily be introduced. Unlike precision, which can be improved by replication, bias cannot be reduced once it is present. Sampling and sample processing procedures must therefore be carefully designed both to minimise bias and to obtain acceptable precision. The most suitable sampling location is the discharge point of a process stream, where increments can be obtained by taking a complete cross-section of the stream with a sample cutter. Sampling devices that take only part of the stream may introduce serious bias and must be avoided. The moisture content and wet mass of the material being sampled are of similar importance to chemical analyses for determining metal content. The accurate determination of moisture content is particularly difficult, because the moisture content of samples can change after the sample is taken, eg due to moisture evaporation. Hence, moisture samples need to be taken quickly and placed in sealed bags or containers that are impervious to moisture. The moisture content should then be determined without delay. To determine wet mass, a range of weighing methods are used in industry, including weighbins, weighbridges, conveyor weightometers and platform scales. The precision and accuracy of these methods vary considerably, so it is important to select a method with the appropriate precision and ensure that the weighscale is well maintained and regularly calibrated.

Jan 1, 2002

The Research Centres Program initiated by the Federal Government and supported by the mining industry has had a major impact on geoscience research and education during the past five years. Eight major university based-Geoscience Research Centres are currently supported by the Government, including four Key Centres of Teaching and Research and a further four Cooperative Research Centres (CRCs). The Research Centres Program has led to a concentration of high quality research and teaching in areas of demand and strategic importance creating strong university - industry linkages and a source of well trained and motivated graduates. Over the last decade Australia's reputation as a leader in mineral exploration and ore deposit research has grown substantially, in part because of the development of the Research Centres Program, and to increased collaboration and interaction between research groups and exploration geoscientists across the industry. During a period when ore deposit research activity has been decreasing in other countries (eg USA, Canada, Japan and most European countries), equivalent research activities in Australia have been increasing, within a well co-ordinated national framework. The future challenge for universities and the mining industry will be to maintain the momentum of the successful research centres in order for the centres to become self-funding over a six- to nine-year period.

Jan 1, 1996

By Eren H

For a hydrocyclone of fIXed geometry, DC, Di, DO and ? are constants, the variable parameters affecting the performance are Qi, Fi, Du and H. (See Appendix 2 for definition of symbols).The relationship between d50c, Qi, Fi, Du and H gives models which can effectively be used for performance predictions. Such models have already been established by Lynch et al and by Plitt.These models have been tried in a limited manner under continuous operating conditions for on-line cowol. For on-line control effective and accurate instrumentation is required for which a new set up is proposed. Using this set up, a new model was established. A feature in this model is that deviations from the norm of operational parameters affecting d50c were considered. It is shown that these deviations generated by the disturbance of one or more of variations in the parameters, can be monitored by a computer and suitable signals generated to control servo mechanisms for restoring the required d50c value.The logic followed in developing the computer software is described and the application of the model is indicated.

Jan 1, 1990

The original design of the Bougainville Copper Limited (BCL) concentrator took cognisance of the constraints imposed by the topography, the need to minimise capital cost, and the need to allow for plant expansion which, it was known, would be necessary to maintain copper and gold production as head grades declined.At the same time as spare slots have been taken up with additional equipment, technological innovations have been embraced whenever there appeared to be a chance of improving the productivity ofexisting equipment, or replacing it with a more efficient alternative.There are many examples of this in the BCL concentrator in the areas of process control, process design, instrumentation, materials handling, equipment design and wear part technology.Current process developments also pursue the latest technology. The development of the Omnicone crusher, flotation control, tailings water reclamation, and the variable speed gearless drive on the No. 13 mill are prime examples.

Jan 1, 1986

By Bonsall EM, Schwabe MR, Hamlyn DA

Historically, most of the gold produced from Kalgoorlie has been derived from the gold and gold telluride Golden Mile lode systems dominantly hosted within the Golden Mile Doler-ite and to a lesser extent, Paringa Basalt. In more recent times the gold-quartz stockwork ore bodies within Unit 8 of the Golden Mile Dolerite at Mt Charlotte have become increasingly imp-ortant.Extensive low grade gold mineralisation has now been defined to the north and east of Kalgoorlie within rock units of the Golden Mile sequence not generally considered to be highly prospective.Two main types of mineralisation have been defined. The first comprises variably mineralised and altered quartz-albite porphyr-ies emplaced within talc-carbonated Hannans Lake Serpentinite (Mystery deposit). There is intense fuchsitic, pyritic and carbonate alter-ation of the serpentinite adjacent to the porphyry bodies. Gold mineralisation is assoc-iated with fine-grained disseminations and veinlets of pyrite and narrow quartz and quartz-tourmaline veining within the porphyry and adjacent fuchsite-carbonate rock. Several sets of vein directions are present, some of which typically exhibit sulphide alteration haloesnnA H] rhina_

Jan 1, 1984

By S F. Rogers, P W. Booth

Digital photogrammetry is revolutionising the task of geotechnical mapping of jointed rock masses and has greatly increased in popularity and sophistication in recent years. Modern commercially available digital photogrammetry software systems can provide geotechnical practitioners with a user friendly tool for rapid data acquisition. The data can be acquired remotely from large exposure areas, some of which may be otherwise out of reach due to restrictions on time, access or safety.Photogrammetry is a complimentary technology to discrete fracture network (DFN) modelling because it can provide the large, statistically significant, spatially located geotechnical data sets required to produce the most robust results. It also provides the flexibility to selectively map structures at a range of scales, depending on the focus of the DFN modelling.Integration of the interpreted rock structure data derived from photogrammetry with modern DFN modelling methods really advances the rock engineering process. The ability to generate 3D fracture models driven by the statistical structural data and conditioned to the features observed by the photogrammetry yields a synthetic rock mass on which improved design methods can be applied. The generation of multiple equi-probable conditioned DFN models allows the use of probabilistic methods for assessing kinematic stability, rock block size distribution as well as a range of other applications.CITATION:Rogers, S F and Booth, P W, 2014. Integrated photogrammetry and discrete fracture network modelling for improved rock mass characterisation and engineering design, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 203–208 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By Pitkajarvi J

Waste rock dilution causes mill feed grade to be lower than mineral resource grade. In nickel mines relative grade decrease (dilution) may be tens of per cent because of irregular ore boundaries and weak wall rocks. Five per cent dilution costs millions of dollars annually in medium size underground mine. In Outokumpu Group selective bench and fill stoping, cable bolting/shotcrete-skin support and fast ore boundary definition (OMS-logg in-hole logging or sludge sampling) are the key tools in dilution control. Commitment of the whole organisation to keep dilution low is also needed. Dilution sources and effects are discussed with examples of the dilution control methods applied in Outokumpu mines.

Jan 1, 1996

By Segnit ER, Boow J

The start up operations of Western Mining Corporation's Kalgoorlie nickel smelter encountered troubles due to the high magnesia content of the concentrates. The flash smelter slags, with higher than normal magnesia content, had a much higher melting point than the normal low-magnesia, predominantly fayalite slags usually produced in nickel smelting. Investigations were made of the structures, melting points and viscosities of the Kalgoorlie smelter slags, as produced, and with additions of silica or lime.

Jan 1, 1980

By Nag D. K

King Island Scheelite is a wholely owned subsidiary of Peko-Wallsend Ltd. The company works two underground mines near the southern end of King Island at the western approach to lass Strait, 240 km south of Melbourne. (See ^igure 1).

Jan 1, 1981

By Burford B. D, Johnson N. W, Rohner P

Under design philosophy, the Hilton concentrator produced lead, zinc and LGM (lead plus zinc) concentrates. The LGM (Iow grade middling) concentrate was produced by combining coarse middling streams from the lead and zinc circuits, regrinding and subsequent flotation. Mineralogical examination of the zinc circuit middling stream prior to regrinding suggested that production of zinc concentrate from the zinc circuit middling stream should be possible by rearranging existing plant equipment. Laboratory testing of samples of plant products, however, showed that regrinding combined wi th the usual reagent suite was nO1 sufficient to produce a zinc concentrate of the required specifications.Examination of the process water highlighted a problem with dissolved salts in the circuit water, which was solved by in-circuit precipitation of the dissolved ions with soda ash. Implementation of the procedure in the concentrator effectively transferred to the zinc concentrate all sphalerite previously recovered to the LGM concentrate.

Jan 1, 1994

By Hayes P. C

The reduction of small, dense zinc oxide (ZnO) samples in CO/CO2, and CO/N2 gas mixtures has been investigated at temperatures between 900 and 1100¦C. The microstructural characterisation of the reacted and partially reduced samples was complemented with measurements of the rates of the reactions. The mechanisms and kinetics of reduction of zinc oxide were found to be dependent upon the CO partial pressure, the oxygen potential of the gas mixtures, temperature and degree of reduction.

Jan 1, 1991

By Martin T

High methane content of the medium volatile metallurgical coal mined from the Coal Basin mines causes very difficult mining conditions. Rapid desorption into the mine ventilation system limits coal production, requires huge fresh air quantities and creates mine safety problems. In workings deeper than 2000 ft (600m) gassy coal and heavy cover create outbursting conditions. Cross-measure methane drainage has reduced ventilation requirements on advancing faces, but degasifica- tion of virgin coal is needed to improve mining Conditions.

Jan 1, 1982

By Doyle R

Underground operations commenced at Tower Colliery in late 1978 and the early prevailing mining conditions in the worked seam were considered poor as a result of high stress and geological disturbances. This suggested that outbursting activity may be a possibility. The colliery has since recorded a total of 13 individual outburst incidents, all of which have been associated with the same dyke and strike-slip fault zone. This paper depicts the geological conditions and presents the results of investigations undertaken at the time of these outbursts.

Jan 1, 1986

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 Woodhouse M, Drew GJ, Andrews DL

The Honeymoon nickel sulphide deposits are located 45 km south of Wiluna in the 2.7 Ga old Agnew-Wiluna greenstone belt in the NE of the Yilgarn Craton (Figure 1). Both disseminated and massive nickel sulphide deposits are present within the deformed and metamorphosed Honeymoon Well ultramafic complex and are hosted by distinctly different komatiitic lithologies (Gole et al, 1996). The deposit styles and host rock lithologies reflect formation in markedly different volcanic settings. Metasomatism has affected parts of the ultramafic complex, including sections of the sulphide deposits, and has had a marked impact on mineralogy and bulk sulphide compositions. The present indicated resource is 158 Mt at 0.71 per cent Ni in four deposits (0.4 per cent Ni cut-off, resources above 300 m depth, December 1995). This includes a massive sulphide resource of 2.5 Mt at 3.36 per cent Ni.

Jan 1, 1996

The economic significance of a fundamental understanding of the mineral pyrrhotite is dis- cussed. Particular emphasis is placed on the relationship of other sulphide minerals to the pyrrhotite when it is the major sulphide mineral present in an ore body. Studies of the Kambalda nickel deposit are used to give a better under- standing of (a) the genesis and other character- istics of a particular ore body (b) the textural relationships between pyrrhotite and other sul- phide minerals (c) magnetic properties of natural pyrrhotite, and (e) the oxidation and supergene processes that take place in a sulphide ore body.

Jan 1, 1972

By Beattie T. A

The ability of explosives to fragment rock has been assessed in small scale trials at the Granite Rock quarry, Baimsdale, Victoria. Three 65 mm diameter holes were fired simultaneously in a five metre bench, and the rock collected, screened and weighed. The mass of fines increased as the explosive strength increased in the series 30(10 ANFOPS

Jan 1, 1990

Pyrrhotite is the predominant gangue mineral at Renison comprising about 60 percent of the sulphides in an average ore blend. It exists as two crystal structures - monoclinic and hexagonal. Monoclinic pyrrhotite is the slowest floating of all minerals but is ferromagnetic and hence recoverable more efficiently by low intensity magnetic wet drum separators than flotation. This paper discusses the installation and commissioning of four 0.915 m x 3.0 m, 0.1 Tesla permanent magnet, wet drum separators prior to sulphide roughing flotation. Planned circuit and process control modifications to better accommodate magnetic separation into Renison's flowsheet will be Discussed.

Jan 1, 1991