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The physical phenomena which influence gas flow in the bosh and hearth of a blast furnace are discussed including the hold-up of slag as a mechanism which can result in a flooding condition. An equation is defined which describes the limitation to wind volume arising from the flooding condition. Implications of the various factors influencing bosh and hearth gas flow on furnace operation are discussed. Coke quality is shown to be the most important factor in the aerodynamics of these zones and coke requirements are defined for the Port Kembla No. 5 BF which has an inner volume of 2670 m3.

Jan 1, 1975

By R Barritt, P Scott, K Albano

Successful closure of tailings storage facilities (TSFs) is an environmental issue faced globally by metalliferous mines. During the initial feasibility and design phase of the mine life importance is placed on the physical stability of above ground TSFs, largely driven by legislative requirements, whilst closure planning is often a secondary consideration. However, as the landform is further developed and constructed attention must be paid to regularly revisit the original closure plan and update it to achieve the best (sustainable) possible outcome for both the environment and stakeholders. A mine in northern Queensland is in the process of developing a closure strategy at their TSF. Appropriate closure measures for the TSF are required to mitigate the impact of any seepage emanating from the TSF on the groundwater and surface water receptors. O’Kane Consultants Pty Ltd (OKC) have provided the mine assistance with the development of a TSF cover system design in order to appropriately manage tailings during operations and to prepare for the facilities’ closure. OKC has collected data since 2007 from cover system field trials located on the TSF. To enhance engineering judgement in the design of future cover systems, calibration of soil-plant-atmosphere numerical models to field data (referred as ‘field response modelling’) were completed. Calibrated model inputs can be used to provide insight into long-term cover system performance as well as a tool for design of the final landform.Following a site investigation, materials characterisation and numerical modelling program various cover system alternatives were developed. Two of the preferred cover system alternatives referred to as Test Plot #1 (TP#1) and Test Plot #2 (TP#2) (Figure 1), were constructed at the site and instrumented. Monitoring instrumentation comprised several nests of in situ volumetric water content and thermal conductivity sensors to measure changes in water content, temperature and matric suction within the cover system materials and underlying tailings waste. Run-off collection buckets and a fully-automated meteorological station were also installed. CITATION:Barritt, R, Albano, K and Scott, P, 2016. Findings and conclusions following ‘long-term’ cover system monitoring – refinement of the conceptual design for tailings storage facility closure, in Proceedings Life-of-Mine 2016 Conference , pp 85–88 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By Alesse V, Belardi G

A new class of collectors, Mercapto-Benzo-Oxazoles (MBO), exerting selective action on copper sulphides in the presence of Pb, Zn and Fe sulphides (galena, sphalerite and pyrite), has been synthesised in co-operation with Enichem's Donegani Insitute. The collectors have a mixed aliphatic-aromatic structure and contain functional groups which form chelates with copper. Some reagents of this class having hydrocarbon chains of various lengths have been laboratory tested on a complex sulphide ore containing chalcopyrite, galena and sphalerite in pyritic gangue. Comparative flotation tests have permitted selection of the best collector for chalcopyrite, namely Methyl-Mercapto- Benzoxazole (MMBO). Systematic flotation tests have been performed with this reagent, varying collector concentration, grain size of the feed, pH and flotation time. The results obtained show that the synthesised collector is much better than potassium-amylxanthate (KAX) as regards selectivity towards Pb and Zn. Moreover, it is possible to work at natural pH (6-7) and the flotation rate is higher. In fact in the rougher stage with 80 g/t of collector at natural pH, a copper grade of 7.14 per cent was obtained with a recovery of 73.87 per cent, while the grade with KAX did not exceed 2.11 per cent for a recovery of 73.54 per cent. The amount of Pb and Zn reporting in the copper concentrate was eight per cent and ten per cent respectively, while with KAX it was no lower than 24.34 per cent and 22.71 per cent in that order. After two minutes flotation a copper grade of 5.2 per cent with 52 per cent recovery could be attained, against a grade of 2.5 per cent and a recovery of 44 per cent in the case of KAX. The efficiency of this new collector has been ascertained on two samples of complex sulphide ores of diverse mineralogical composition.

Jan 1, 1993

The Inglewood Gold Project consists of several titles in and around the Inglewood and Wedderburn Goldfields which were purchased from Strata Mining Corporation (now Excalibur Mining Corporation). The Inglewood goldfield has a historical production of approximately 160 000 tonnes at 23 grams per tonne. The company has reopened and developed the Maxwells reef, picking up a high-grade shoot (Max Shoot) identified and worked by Goldquest et al up until 1994. Production ceased on a low gold price, rapidly reducing vein size and a requirement for further development. Greater Bendigo Gold Mines Ltd (GBM) has undertaken the development and encountered the mineralised vein in an increasing size setting with high grades and the existing mine development has access to a further shoot to the north (Max North Shoot). The Maxwells reef also contains the Woolf shoot south of the Maxwells shaft and an inferred resource of ~20 000 ounces is contained from 60 m below surface. Best intersection 2.9 m at 50 g/t. The Maxwells reef area produced approximately 20 per cent of the Inglewood goldfields production and GBM is preparing to increase its exploration efforts across the rest of the field. A processing plant has been constructed at the Maxwells mine site, which is capable of treating tailings, hard rock and alluvial material utilising gravity recovery. The existing Maxwells tailings have been excavated and treatment commenced. It is intended to produce a sand product from the tailings for resale and to reduce the storage requirements per tonne. Several large water dams constructed by Goldquest in the 1990s are being re-engineered to enable storage of significant tonnages of tailings. A level of surface and underground production is planned for 2008 and this is to be expanded into 2009 and beyond. The long-term future at Inglewood is envisaged as structural repeats at depth below the current workings and a project plan to gain deep access will be prepared on successful drilling results.

Jan 1, 2008

By D R. Andrew, K T. Morrison, J F. Tiedgen

Waste blasting in iron ore operations can pose a number of technical challenges, including blasting through variable geology and blasting soft ground in wet conditions. Blast patterns are designed to be loaded with a specific range of explosives with unique characteristics and properties. Each explosive product will produce an optimal blast outcome for a given set of blast parameters and ground conditions. Sites characterised by softer rock typically require low-density, low-energy explosives. Historically, these products have contained a high ratio of porous ammonium nitrate prill and are only suitable for dry blastholes. When blastholes within a pattern are found to be unsuitable for such explosives due to wet, damp or muddy blasthole conditions, a new product is selected. While it is easy to switch products to match blasthole conditions, the different properties of the new non-ideal product can impact blast performance and increase loading times and costs.Flexigel™ is a solids-sensitised emulsion blend suitable for loading at variable densities and energies in dry, damp, muddy or wet blastholes. It is a universal product that can be loaded to match ground and blasthole conditions or complement other explosive products.At Fortescue Metals Group’s Cloudbreak site, Flexigel™ was trialled through a series of matched pair blasts in order to optimise blast outcomes in conditions that were non-ideal for existing explosive products and to reduce the overall cost of drill and blast operations. Flexigel™ yielded improved instantaneous dig rates and improved loading efficiency when compared to a traditional emulsion blend. The results also indicated that variable-density and variable-energy products afford greater flexibility for optimising blast outcomes across all ground and blasthole conditions trialled.Trials of Flexigel™ at Cloudbreak have shown that a variable-density solution is available for conditions where traditional explosive products are non-ideal. As such, Flexigel™ is able to fill a major void at any operation where the desired low-density, low-energy explosive product must be substituted for a more expensive traditional emulsion blend or heavy ammonium nitrate/fuel oil.CITATION:Andrew, D R, Morrison, K T and Tiedgen, J F, 2015. Flexigel™ – a variable-density solution, in Proceedings Iron Ore 2015, pp 413–418 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By H P÷llmann

Calcium aluminates, calcium aluminate ferrate and calcium aluminate sulfate were synthesised by solid-state reaction, sol-gel method, a self-combustion method and by a polymeric precursor process. For chemical sintering methods the base chemicals CaO, CaSO4, Al2O3 and Fe2O3 were used. As precursors for sol-gel synthesis metal nitrate hydrates and Al2O3-Sol were used. In order to synthesise pure phases by a self-combustion reaction glycine was used as fuel and nitrates as metal components. In the polymeric precursor process metal nitrates and diluted H2SO4 were used as metal components and the resin was made using citric acid (C6H8O7) and ethylene glycol (C2H6O2). Precursor phases synthesised by these different methods were sintered step-by-step in order to investigate the crystallisation. Further on single phases were hydrated and their hydration behaviour was studied by heat flow calorimetry, X-ray diffraction and cryo-transfer scanning electron microscopy. Due to the different synthesis procedures different hydration reactions and microstructures of the phases will be shown.

Jan 1, 2008

By Aspinall T. O, Loch R. J, Bell L. C

Design of reshaped spoil surfaces is an important pan of rehabilitation of spoil piles resulting from open-cut coal mining. To achieve the optimum design, it is necessary to make accurate predictions of soil losses from spoil piles. Predictions can be based on data gathered using laboratory and field rainfall simulators and field plots. These data are used to derive input parameters for erosion prediction models. Model input parameters include rainfall erosivity, spoil erodibility, sediment size distribution, runoff, soil loss and peak runoff rate. Model outputs can be used in design and include predicted sediment size distribution and predicted soil loss.The traditional method of gathering input data is monitoring field plots. This method is very expensive, must be done on a long-term basis and is affected by irregular rainfall. Long-term field plots are necessary to obtain data that can be applied to empirical prediction models such as the Universal Soil Loss Equation (USLE).

Jan 1, 1992

By P M. Larionov, V I. Zaikovskii

Transmission and scanning electron microscopy together with X-ray spectral microprobe analysis were used to investigate the structure and chemical composition of pathological calcified formations on the bioprostheses of heart valves. Controllable synthesis was carried out under the conditions (T = 37¦C, pH = 7.4) when the ion composition of the main elements (Ca, P, Mg and NaCl) is close to their concentrations in blood plasma. It is proposed on the basis of the obtained results that the formation of the hydroxyapatite of calcific inclusions on bioprostheses occurs as a result of spontaneous precipitation in the blood plasma. One of the factors determining the formation of massive calcified bodies on the bioprostheses of heart valves can be decreased magnesium concentration in blood.

Jan 1, 2008

By Parkes DB

The excavation of sandstone of generally medium strength for the Liverpool Link Line by Dosco Mark 2A Roadheaders has demonstrated the versatility and good performance of road- headers in suitable rock formations. A description is given of the strata traversed by the tunnels together with descriptions of equipment and crews, excavation sequences, operating difficulties and the results achiev- ed. In addition tunnel construction is des- cribed for a difficult section where there was only O.Sm clearance between invert and a four lane vehicular tunnel below, and O.5m clearance between tunnel crown and a century old sewer above.

Jan 1, 1976

The excavation of sandstone of generally medium strength for the Liverpool Link Line by Dosco Mark 2A Roadheaders has demonstrated the versatility and good performance of road- headers in suitable rock formations. A description is given of the strata traversed by the tunnels together with descriptions of equipment and crews, excavation sequences, operating difficulties and the results achiev- ed. In addition tunnel construction is des- cribed for a difficult section where there was only O.Sm clearance between invert and a four lane vehicular tunnel below, and O.5m clearance between tunnel crown and a century old sewer above.

Jan 1, 1976

By Y Zhu, W Liang, P Knights

In recent years, Chinese companies have invested billions in Australian mineral exploration, development and processing. In 2008 - 2009 alone, the Foreign Investment Review Board approved $26.4 B of investment. Much of this investment has been by merger and acquisition (M&A) of Australian resources companies. This paper sets out to investigate how Australian CEOs perceive the cultural and institutional challenges in operating Australia mining companies recently acquired by Chinese interests. HofstedeÆs cultural dimensions and institutional theory from management science were used to develop a structured questionnaire, which was subsequently used to conduct telephone interview of the CEOs of six recently acquired mining companies. Analysis of the survey results indicated that, in all cases, few changes were made to the operational management of the Australian companies post-M&A. The three major benefits for Australian companies as a result of the M&A are the ability to; access long-term debt at lower cost; secure finance for growth plans in financially volatile times; and maintain existing management structures. Some perceived negatives involved longer and more convoluted decision-making as a result of Chinese state approval required for investment decisions. The study identified building æGuanxiÆ and an aversion to losing æfaceÆ as important cultural learnings for Australian CEOs. Maintaining effective communications is regarded as key for successful cultural integration.CITATION:Liang, W, Zhu, Y and Knights, P, 2012. Cultural challenges in Chinese/Australian mining mergers and acquisitions - A CEOÆs perspective, in Proceedings International Mine Management 2012, pp 251-260 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 20, 2012

By J Hartog, V Beehan, D Beeson

Treating an ore blend from five different deposits at Newgold’s Peak Gold Mine (PGM) has always been a challenge due to the inherent variability between each of the orebodies.Operating the processing plant at PGM with a ‘normal’ level of process control and a good operations and metallurgical team has allowed the processing plant to achieve above the name plate design at 102 t/h and recoveries in the order of 92.8 per cent for gold and 88.4 per cent for copper.With a company value and culture of striving for continuous improvement, PGM implemented the Manta Cube® system, an advanced process control system, for the semi-autogenous grinding (SAG) mill, gold leach circuit and tailings thickener over a 12-month period throughout 2012 and 2013.The overall benefits of implementing the Manta Cube® system has led to an increase in mill throughput of at least two per cent, improved SAG mill liner life, a ten per cent decrease in cyanide consumption and a reduction in flocculant of at least 30 per cent with no detriment to the gold and copper recoveries.The entire project had a payback period of less than two months, and the combined benefits resulted in an overall increase in revenue of at least $5 million per annum. This is quite significant for a processing plant the size of PGM.This paper describes the methodology, overall results and economic benefit of applying the Manta Cube® system on-site at Newgold’s PGM.CITATION:Hartog, J, Beehan, V, Karageorgos, J and Beeson, D, 2014. Optimisation of the Peak Gold Mine’s processing plant through advanced process control, in Proceedings 12th AusIMM Mill Operators’ Conference 2014 , pp 335–344 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 1, 2014

By Liu Q, Siefken T. C, Misra V. N

Investigation of the differential flotation characteristics between arsenopyrite and pyrite in a ore concentrate have been carried out on a laboratory Leeds flotation cell. Experimental results indicate that some limited separation between arsenopyrite and pyrite is possible by differential flotation under the conditions of high pH and low pulp redox potential. The best performance in this testwork was achieved by using an oxidizing agent at pH 10.7. Of the oxidizing agents tested, NaOCI gave better oxidizing effect than KMnO4. It has also been observed that the pulp redox potential depends on the pulp pH value. At high pH values a hydroxide layer is formed on the arsenopyrite surface, which has the effect of a depressant on the arsenopyrite.

Jan 1, 1992

Changes in mining technology have led to an increase in the number of underground sulfide dust explosions reported in Australian and overseas mines. Samples collected at the Elura mine consisting primarily of pyrite, pyrrhotite, arsenopyrite, sphalerite and galena, were tested in 8 litre explosion chamber. The dusts were found to be capable of producing dangerous dust explosions with maximum explosion pressures of 440 kPa and rates of pressure rise of 5200 kPa/s. The hazards of a sulfide dust explosion are associated with the pressure wave and flame front of the explosion and the toxic gases remaining after the explosion.

Jan 1, 1984

By V Seedwell, P H. McGuckin

The Broken Hill Proprietary Company Limited (BHP), started as a silver-lead- zinc mining company in Broken Hill, New South Wales, Australia in the 1880s. Since then it has diversified into the resource industries of steel, iron ore, coal, petroleum and copper. BHP World Minerals, is a Business Group of BHP which is one of the worldÆs largest and most diverse mineral resource enterprises. BHP supplies raw materials for steelmaking, copper concentrate and other mineral commodities to customers in more than 45 countries. BHP World Minerals has operations throughout the world - in Australia, the United States, Brazil, Zimbabwe and Canada. Commodities produced by BHP World Minerals currently include silver, lead, zinc, titanium minerals, platinum group metals and coal. The challenges in the improving performances in safety arena are common to our industry and BHP operations. This paper outlines the vision and values that have been fundamental in assisting BHP Cannington search for and implement a safety system addressing behavioural matters.

Jan 1, 1998

By P Duuring

Late-Archean banded iron formation (BIF)-hosted deposits in the Yilgarn Craton of Western Australia are less well understood compared to the larger Paleoproterozoic, Superior-type BIFhosted deposits of the Hamersley Province. The Weld Range greenstone belt, in the Murchison Domain of the Yilgarn Craton, hosts two Archean, high-grade deposits, Madoonga (68 Mt resource at 57.7 wt per cent Fe) and Beebyn (62 Mt resource at 59.6 wt per cent Fe, ASX announcement 2008). Five main types of high-grade (>55 wt per cent Fe) iron mineralisation at Weld Range each display characteristic grades, tonnage, and contaminant levels, which affect exploration strategies and beneficiation methods:1. ‘Residual’ ore formed as a result of two generations of hypogene alteration of BIF. The first alteration phase replaced silica-rich bands with siderite and/or Fe-rich dolomite; the second phase involved the removal of carbonate gangue minerals and the concentration of residual Fe oxide-rich bands in the BIF via volume reduction. The product is a high-grade, high-tonnage Fe orebody, with minor contaminants.2. Magnetite-bearing shear and fault zones cut BIF along lithological contacts. These zones of secondary magnetite formed as a result of the addition of hypogene magnetite via the circulation of Fe-rich, hypogene hydrothermal fluids through BIF. This type of mineralisation produces narrow (low-tonnage), high-grade magnetite-rich ore zones with high levels of contaminants (eg SiO2, Al2O3) due to the difficulty in mining these zones.3. Specular haematite ± quartz-bearing shear and fault zones cut residual orebodies and magnetite bearing structures. They share similar characteristics to magnetite-bearing structures.4. Goethite-haematite supergene ore zones are controlled by brittle faults that cut BIF. These faults promoted the flow of supergene fluids through BIF and resulted in large ore zones with variable Fe grades and contaminants.5. Detrital deposits comprise transported BIF fragments and are intensely goethite-haematite supergene-altered. These orebodies are locally extensive, with moderate Fe grades.

Jul 11, 2011

By P J. Jacobs

FORACO is the third-largest global drilling services company, and recently celebrated its 50th anniversary. The company’s historical roots are in French-speaking West Africa, delivering hydrogeological drilling services to resource companies, villages and regional centres. Today, FORACO operates over 300 drill rigs in more than 20 countries.The Asia Pacific region of FORACO runs a fleet of 37 late model drilling rigs servicing the diamond drilling, reverse circulation, coal, coal seam gas and hydro drilling sectors.FORACO Australia has extensive experience delivering large diameter coring (LDC) samples to the resource community. In the past three years, the company has been involved in six 8? coring projects in a variety of geographies and geologies, including iron ore, coal and uranium. FORACO has developed proprietary equipment and techniques to deliver cost-effective LDC samples with outstanding core recovery.The FORACO LDC sampling system is hands free, with mechanised rod and corebarrel handing to minimise the risk of manual handling injuries. Sample volumes are six times PQ (the common industry standard for large core samples), with core recoveries consistently above 96 per cent in extremely difficult formations.Eight inch coring is a conventional coring system suited to hole depths up to 150 m. For deeper applications, FORACO has recently invested over $4 M in a 6? wireline coring system capable of achieving depths of 300 m.CITATION:Jacobs, P J, 2014. Large diameter core sampling, in Proceedings Sampling 2014 , pp 71–76 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 29, 2014

The transgressive sedimentary sequence of the Notnnea Basin contains rhyolitic lavas and less voluminous mafic and intermediate volcanims of shoshonitic affinities which erupted simultaneously during the late Cretaceous. The shoshonitic volcanism shows a trend from early inafic to younger evolved intermediate lithologies. The rhyolites are consistently calc- alkaline. There is no evidence of 'mixing, of, the two magma types. The shoshonitic volcanism is the result of a short-lived subduction event related to sprcadime in the New Caledonia Basin and involved reactivation of an earlier Mesozoic subduction zone.

Jan 1, 1995

In August, 1975, North Broken Hill Limited announced that an intersection of 37.3 m of high grade lead-silver-zinc mineralisation, assaying 26.2 per cent Pb, 495 g/tonne Ag and 21.2 per cent Zn had been obtained at its Mine at Broken Hill, 520 m north-east of its No. 3 Shaft and slightly below the No. 36 level (1581 m). Subsequent drilling confirmed the presence of the extension of the Broken Hill Orebody on the north-western side of the Globe Vauxhall Retrograde Shear Zone and defined 1.8 million tonnes of high grade mineralisation. The area containing this mineralisation was subsequently named the Fitzpatrick Area in tribute to the late Mr. W.E. Fitzpatrick a former Member of the the Board and Manager of the Ccnpany's Broken Hill operations. This paper describes in brief the exploration programme leading up to the discovery, the general geology of the area and the proposed future exploration progranme for further extensions of the orebody within the mining leases of North Broken Hill Limited.

Jan 1, 1983

By Borsaru M, Wylie AW

A neutron irradiation technique has been developed which is suitable for the determinat- ion of the iron and aluminium content of iron ore fines (-6 mm particle size) on a moving rubber conveyor belt. The determination of iron entails measure- ment with a NaI(Tl) gamma ray detector of the characteristic prompt gamma rays (7.64 MeV) due to thermal neutron capture in iron, while the determination of aluminium is based on thermal neutron activation analysis. For the latter a second detector must be placed down- stream to monitor the 1.78 MeV gamma radiation emitted after activation of aluminium. Although conveyor speed has no effect on the Fe measurement, it has an adverse influence on the aluminium signal, and the belt speed should not exceed 0.1 m/s if good accuracy is required. Static trials on a 460 mm rubber conveyor belt with constant ore geometry indicate that for iron an accuracy of ¦ 1.2% Fe (2a) can be achieved for crushed run-of-mine ore at

Jan 1, 1978