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A continuous casting machine, of the Concast curved mould design casting billets in four strands, was commissioned at the Newcastle Works of The Broken Hill Proprietary Co. Ltd., in November, 1967. Quality assessment of early casts from this plant indicated that steel cleanliness was sometimes inferior to that of equival- ent ingot cast steel. Extensive trials to develop a modified deoxidation technique were not successful in improving clean- liness to the desired level. A "contra-flow" gas shroud, to cover the steel stream between the tundish and the mould, was developed, and proved successful in achieving the required levels of product cleanliness. The inclusion content of six grades of steel ranging in carbon content from 0.10 to 0.70 per cent is examined, and an attempt is made to explain theoretically some of the results obtained.

Jan 1, 1972

The heavy media cyclones at Argyle Diamonds are subjected to extremely abrasive service conditions and have been the subject of a development program from the time the first ore was treated in the AKl processing plant. In the past ten years the cyclones have been re-engineered from a standard DSM design, in which some components would only last four days, to the current Argyle design in which the minimum component life is 175 days. Development has focused upon the elimination of turbulence in the cyclone and combating unavoidable abrasion through the use of appropriate wear materials.

Jan 1, 1996

Cannington Mine is an underground, hard rock, metalliferous mine located in North-Western Queensland, Australia. Weld mesh is installed to prevent the failure of rock from between the installed reinforcement elements. Corrosion reduces the capacity and life expectancy of mesh and presents a real hazard to underground personnel and equipment as it reduces the effectiveness of the support system. Corrosion influences the economics of the mining operation through the need to conduct rehabilitation of the ground support which involves re-installing new mesh or shotcreting over the affected mesh to protect it from further corrosion. The requirement for rehabilitation is determined by the geotechnical engineer based on an individual visual assessment with little or no engineering input. It was identified that a more quantitative method was required that considered the safety and economic risks involved. A project was undertaken to develop a simple method to evaluate corroded mesh and to provide selection criteria for rehabilitation. A weld mesh corrosion classification has been developed that relates the average wire diameter of corroded mesh to the remaining capacity of the mesh. Accompanying selection criteria provides recommendations as to when rehabilitation may be required based on the estimated residual mesh capacity, the remaining development life, and the level of personnel exposure.

Nov 25, 2010

By A Giblett, S Hart

"In 2015 operations under the ownership and/or management of all Newmont Mining Corporation subsidiaries (Newmont) produced 5.7 Moz of gold and 619 Mlb of copper from mining operations in five countries, with well over 100 Mt of ore processed by various grinding technologies. Processing methods used in the extraction of metals include flotation, oxidation, conventional cyanidation and heap leaching. The grinding technologies applied in milling operations feeding metal recovery processes include conventional wet grinding semi-autogenous grinding (SAG), rod and ball, dry grinding, concentrate regrinding and ultra-fine grinding, and ball milling of high pressure grinding roll product. SAG/ball (SAB) configurations represent the dominant comminution flow sheet within the company and the circuit configurations employed include SAB, SABC-A, SABC-B and single-stage (SS) SAG milling, with SAG mill feed ranging from run-of-mine (ROM) ore through to secondary crusher product. The collective experiences earned from designing, operating and debottlenecking these various comminution circuits provide many lessons that can be applied to the design and optimisation of future operations. This paper provides an overview of Newmont’s diverse comminution circuits, discusses recent performance and offers some insight into optimisation and design considerations based on recent experience in both endeavours.Citation:Giblett, A and Hart, S, 2016. Grinding Circuit Practices at Newmont, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 293–302 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

By F R. M Pires, R M. Carvalho

Supergene processes in banded iron formation (BIF) result in important dissolution, material transport and simultaneous disorder of the residual bands. The rock physical properties such as density, porosity and rheology change during the weathering attack. The itabirite, Paleoproterozoic metamorphic BIF from Quadrilßtero Ferrffero (QF) û Brazil, shows several weathered facies. Strong linking between topographic surface, rock density and iron grade occurs within the weathered zones. This linking is due to partial dissolution of silica and carbonate from itabirite and gravitational rotation and break of the remaining blades, generating kink-like slump structures. The original itabirite density, 3.7 t/m3, decrease at the first leaching steps, until 2.7 t/m3, and increase at the end of the leaching process until 3.6 t/m3. Iron grade increases from 38 per cent to 68 per cent and depressions (sinkhole), subsequently filled by Cenozoic basinal sediments, are developed over the enrichment zones. The formation of important supergene iron ore deposits of QF is intimately related to such a process. Several iron deposits at QF, such as Pico do Itabirito, Fßbrica Nova, Casa de Pedra, Tamanduß, -gua Claras, Cappo Xavier, etc., reveal the aspects related to the proposed evolution, implying that the formational process of the soft iron ores had a regional character. Granular medium model helped in the understanding of the development of the structure and the formation of the deposits. A numerical model has been developed in order to simulate a leaching system in a two-dimensional matrix, composed of two types of materials: leachable and unleachable. Equal volume proportion and vertical banding were considered. Drilling data was used as multipoint attractors to remove leachable matrix nodes.

Jan 1, 2002

By Y K. Ji, B J. Chung

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

Jul 13, 2015

By F F. Pitard

The comparison between J Visman and C O Ingamells’ works with P M Gy’s works has been the object of intense debates in the past. Such negative debates inevitably resulted in a loss of many good opportunities. The author’s long experience in applying works of these three authors led to the pragmatic conclusion that it is relatively easy to integrate everything Visman and Ingamells created into the Theory of Sampling; therefore, it is suggested that the compatibility has been vastly overlooked, and a correction for such anomaly is recommended. It is important to emphasise that Visman and Ingamells works may be beneficial and provide relevant, harmonious additions in some areas, and ultimately offer attractive possibilities to sampling practitioners. Such additions may enhance our capabilities to predict sampling difficulties by using a stronger strategy and to design better sampling experiments that would allow us to further understand the heterogeneity of minor constituents, and especially trace constituents. Basically, the suggested integration is essential for sampling trace constituents in the environment, in food, in chemicals and in the pharmaceutical industries.CITATION:Pitard, F F, 2017. Integration of Visman and Ingamells’ works into the Theory of Sampling – a necessity to expand possibilities in sampling practices, in Proceedings Eighth World Conference on Sampling and Blending , pp 55–62 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2017

A commonplace, sometimes overlooked or taken for granted, article of everyday existence is the tin can. Produced from thin gauge low carbon steel, and commonly coated with a mere 60 millionths of an inch of pure tin, the product is however strong and corrosion resistant. Tin-plate serves a myriad of purposes-the most important being to meet the requirements of the canning industry. Australia's newest steel product, tin-plate, was first produced on a commercial scale during the early part of August, 1957. The commissioning of the Hot Dip Tinning Plant (Fig. 1) of The Broken Hill Proprietary Co. Ltd. at Port Kembla, marked the culmination of a proposal dating back to 1939, the advent of World War II having caused its deferment to the present time.Cornish tin is known to have been exported as early as 300 B.C. to Syria and tinned vessels existed even in the year A.D. 23. The tin coating of plate could be described as an ancient art, believed to have had its origin in Bohemia in the thirteenth century. During the next 450 years, the process spread through Saxony to Pontypool in Monmouthshire, but it was a further half century before any measure of success was obtained.Perhaps the two greatest milestones in tin-plate manufacture were the rolling of iron plates first carried out in 1728, thereby outmoding the hammer formed sheet, and more recently, the development of the electro-deposition process. By the nineteenth century, several important changes had arisen; namely, the substitution of steam for water power, coke for charcoal in the production of the base metal, and...

Jan 1, 1958

The published liquidus data on the Pb-PbS system have been correlated on the basis of one-coefficient Margules equations. Thermodynamic properties of the components of this system have been obtained, and it has also been found that the calculated miscibility gap of this system exists over a very narrow range of temperature (1041 to 1058°C).

Jan 1, 1972

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

By Y Wan, L Liao

Organo-montmorillonites were synthesised by intercalating different amounts of dodecyl trimethylammonium bromide, cetyl trimethyl- ammonium bromide and stear trimethylammonium bromide into montmorillonite layers, and were used for the adsorption of 17b-estradiol in aqueous solution. The adsorption kinetics and thermodynamic of 17b-estradiol onto organo-montmorillonites and the effect of pH on the adsorption capacity of organo-montmorillonites for 17b-estradiol were studied. The adsorption isotherms at 20¦C, 35¦C and 50¦C were measured. Results show that organo-montmorillonite has a high affinity for 17b-estradiol. More 17b-estradiol can be adsorbed on to organo-montmorillonite and the adsorption is more rapid at a lower temperature. The montmorillonite intercalated with cetyltrimethyl- ammonium bromide with the amount equivalent to one times of its CEC has the highest adsorption capacity. For all organo-montmorillonites synthesised in this study, an optimum pH (around nine) for the adsorption of 17b-estradiol exists. Before this pH 17b-estradiol uptake increased with increasing pH. After that the 17b-estradiol uptake decreased with increasing pH. Simulation of the isotherms indicated that the adsorption of 17b-estradiol onto organo-montmorillonites is a spontaneous and exothermic process. Endocrine-disrupting chemicals (EDCs) are the focus of current environmental concern, as they can cause adverse health effects in an intact organism, or its progeny, subsequent to endocrine function. Most EDCs are man-made organic chemicals (industrial chemicals, crop protection products, antifouling compounds, pharmaceuticals and personal care products). In addition, EDCs can be naturally occurring in the environment (eg the natural female hormones estrone and 17b-estradiol). Therefore EDCs, especially estrone and 17b-estradiol, are ubiquitous in the aquatic environment receiving sewage inputs. Estrogen and 17b-estradiol are among the most potent of all EDCs and are sufficiently stable to survive present sewage treatment processes and are reactivated during those processes through deconjugation (Clara, Strenn and Saracevic, 2004; Zhang and Zhou, 2005; Fukuhara et al, 2006; Butler and Guilbault, 2006; Volpe et al, 2006; Ren et al, 2007; Zeng and Li, 2007). In comparison to traditional contaminants such as pesticides, the concentrations of the most potent EDCs are low, generally within ng/one range. The current sewage treatment processes have limited capacity in removing certain EDCs (eg 17b-estradiol, C18H24O2) It is therefore essential to install additional treatment processes to remove them from wastewater before discharge (Zhang and Zhou, 2005; Fukuhara et al, 2006; Lee, Jung and Kim, 2006). Adsorption is considered to be a possible way to remove EDCs from aqueous solution. Various adsorbents have been studied, including chitin, chitosan, ion-exchange resin, activated sludge, activated carbon (Clara, Strenn and Saracevic, 2004; Yoona and Westerhoffa, 2003; Zhang and Zhou, 2005; Fukuhara et al, 2006; Ren et al, 2007). Studies have shown that organo-montmorillonite has a high affinity for organic pollutants (Li, 1997; Zhu et al, 1998; Han et al, 2001). The aim of this work is to investigate the feasibility of removing 17b-estradiol from aqueous solution by adsorption onto organo-montmorillonite.

Jan 1, 2008

By P Gleeson, J Coombes, P Suresh, T McLennan

The last 20 years have seen a dramatic rise in the use of 3D visualisation and modelling for geological data, but there has been relatively little effort to do the same for the variogram models that underpin the standard estimation algorithms used by the mining industry.For kriging, one of the most used geostatistical estimation methods, specifying a variogram model is a critical part of the modelling process. Experimental variography is the primary method for approximating the theoretical variogram function from the available sample data, and then determining an appropriate variogram model from the approximations.The traditional tools used for experimental variography are limited to looking at subsets of the data and are often presented without reference to geographic space and geology. It can be difficult to know what input data is being used for a particular experimental variogram, and whether there is enough support in the experimental variograms to propose an appropriate model.To overcome these limitations, an innovative approach called situational variography has been proposed that visualises variograms in 3D alongside contextual geological and geometric data. Presenting variograms in this manner aids understanding of how the spatial variance relates to the underlying data.A 3D extension of the 2D radial variogram maps will be investigated which allows for dynamic exploration of the full experimental variogram cloud. These 3D experimental variograms are much easier to visualise situationally.A workflow for situational variography will be outlined and the advantages of the situational approach will be illustrated using a porphyry copper deposit.CITATION:Gleeson, P, McLennan, T, Suresh, P and Coombes, J, 2017. Situational 3D variography – determining the variogram in the context of geology, in Proceedings Tenth International Mining Geology Conference 2017, pp 191–198 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

By L Soares, W T. Hennies, F Fujimur

Barra Bonita reservoir, located in the Sao Paulo State, Brazil, has been mainly used for local navigation and electricity generation to supply a prosper region in the country. Sand mining activities in that area have an important social and economic meaning for the local community. In this reservoir there are several sand mines that produce around 45 000 m3 of sand a month. These deposits were rich in material used as concrete aggregate in the civil construction. However, nowadays a significant increase in the demand of gravel can be observed, representing a serious productive problem. This material hasnÆt been well accepted by the market and, through the years, it was disposed at open sky in piles as waste deposits. This deposits have caused environmental problems like visual impact, reduction of free spaces outside and inside the mine, source of material to erosion and sedimentation processes in lower areas, flooding as a result of the filling up process in the drainage system, among others. For a lack of an appropriate technological characterisation, this material have been mainly used to pavement internal and external areas in the mine, with lower cost associated. With the purpose of evaluate the usefulness of this material in the conventional concrete, there were conducted several tests in the disposed residue including petrographical, physical, and chemical characterisation. The petrographical analysis and the preliminary results of the study showed that the material reacts with the alkalis that are present in the conventional cement (CP-II-E-32). In order to make the application technical and economically possible a research was developed seeking forms to correct this characteristic by adding special cements with high pozzolana content. The results of the technological, physical and chemical characterisation of the products indicated the technical viability of the use of that material. The study also allowed projecting environmental improvements resulting in the elimination of the waste piles.

Jan 1, 2003

The process of hydraulic transport through pipelines, world-wide well known for the trans- port of fine-grain solids is also being used to a greater extent in mining for the handling of 1rimarily coarse-grain solid - water mixtures r the removal of, for instance Coal and waste mixtures after coal winning rising hydraulic monitors, lings for backfilling underground and :her tailings and flotation waste to A large-scale test unit was taken into service at the Bergbauforschung GmbH (Mining P',search Company) in Essen-Kray, GFR, to ¦urther improve this technology. The unit was :fanned and built by Krupp Industrie- and +hibau of Duisburg in cooperation with i r

Jan 1, 1980

By S O. Hille

Modern remote mining operations in Australia are more commonly trending towards fly-in/fly-out (FIFO) sites. This trend is driven by numerous factors including increased business centralisation, reduction in operating costs, and a desire to live in coastal cities that offer closer family networks and a greater diversity of facilities. Consequently, the resource development industry has had to adapt. When WMCÆs Mount Keith Nickel Operation commenced operations in 1994, it was developed as FIFO for its entire workforce. Since then, there have been several permutations of rosters within a 21 day compressed work cycle including the 14/7 cycle. This paper discusses a case study of the change in management process to the 9/5 work cycle focusing on minimising fatigue in the workplace. It includes the discussion of the business case, employee reaction and the practical application. The impact of the best practice change after 18 months is discussed.

Jan 1, 2002

The Japanese Government promulgated the æLaw Concerning Special Measures Against DioxinsÆ on 16 July 1999 and it was enforced on 15 January 2000. This is a unique law specialised to protect the environment by the control of dioxin emissions from waste incinerators and several industrial processes. In this law, a few metallurgical processes other than waste incinerators are designated as æspecified facilitiesÆ emitting certain dioxins. Thus, emission standards for dioxins to the air were set for electric arc furnaces (EAF) for steelmaking, iron ore sintering, zinc recovery from EAF dust and aluminum recycle processes. In this paper, the inventory of dioxin emissions for Japan and the recent research and development to reduce emissions from those processes are introduced. Further, some details on the formation mechanism of dioxins and future subjects for effective control of their emissions are discussed.

Jan 1, 2002

People in the work environment (and often elsewhere) are seen as a commodity (we use them for our purposes).The general accepted view of a Company is that shareholders are "The Company" and that they employ people to utilise their money in a particular field to generate more money to give a return on investment. To achieve this, capital equipment is purchased to fulfil a task and people are employed to use this equipment. Equipment and people are commodities purchased with money.The focus of this approach is MONEY. The equipment and people, and the use of them, determines the amount of money that can be generated. In this approach people are motivated by financial concerns. The harder the times the more money becomes the focus.

Jan 1, 1998

By L B. Sukla, V N. Misra

Microbial desulfurisation of coal has significant advantages over physicochemical desulfurisation processes since the former process selectively removes the inorganic sulfur compounds and heavy metals without significant carbon loss. The purpose of this study was to improve the desulfurisation yield of a coal sample from northeastern coalfields, Assam, India using microbial technique. The coal sample contained 2.13 per cent of total sulfur and 2.59 per cent of ash. Stirred tank reactors of 40 L capacity were operated in batch mode. Initially, the reactor was fed with 40 L of slurry containing ten per cent (w/v) coal, ten per cent (v/v) inoculum of mixed culture of mesophilic acidophiles, native to coal itself and the requisite amounts of constituents for 9K medium without added ferrous sulfate. The percolate of the reactor was then used to seed the medium for the next experiment. The purpose was to obtain a better adapted and more active biomass which would give a better desulfurisation yield for coal. Further studies were conducted in the bioreactor, fed with 40 L of slurry containing ten per cent (w/v) pulp density of coal, ten per cent inoculum (derived from previous studies) and the medium, supplemented with ferrous sulfate. Results showed an increased total desulfurisation yield of 43 per cent in the latter treatment in comparison to the previous one, where the desulfurisation yield was only 23 per cent. The findings also demonstrated the convenience of using inocula derived from coal, where 50 - 60 per cent of pyritic sulfur was removed, while chemical desulfurisation is of little significance with the majority of coal types. The ash content was also reduced to 1.74 per cent as the low pH of the process caused dissolution of a number of common minerals present in the coal.

Jan 1, 2004

The Peelwood district of New South Wales is located some 65 miles south of Bathutst on the Tuena-Crookwell road. A number of occurrences of lead-zinc-copper ore are known from this district but only three mines, Peelwood, Cordillera and Mt. Costigan, have achieved any significant production. The purpose of the paper is to describe the mineral composition of sulphide ores from these three localities.HISTORYNo published information on the geology of the Peelwood area is available. Came (1899) reports that, at the time of cessation of mining operations in 1888, the Peelwood mine had produced some 600 tons of copper metal and regulus, the Cordillera mine had yielded 9000 tons of ore at the recoverable grade of 2·5 per cent Pb, 2·5 per cent Cu, 90z/ton Ag and 1 dwtjto:p. Au, but that no production figures were available from Mt. Costigan. No further work was carried out on these properties until 1951 when the Electrolytic Zinc Company of Australasia instigated a programme of geological mapping and exploratory diamond drilling (Whitten, unpublished data, 1953). The Peelwood district was recently mapped by Mutton (unpublished thesis, 1960) from whom the following geological summary account was taken.GENERAL GEOLOGYAll rocks in the Peelwood area belong to a series of interbedded fine grained sediments and volcanics that are thought...

Jan 1, 1961

The application of new and currently practised mining techniques in new areas and at greater depths necessitates considerable and immediate research effort. This effort is aimed at identifying the factors which make a particular method suitable and economically viable in a given geological, structural and operational environment. These factors, together with greatly enhanced knowledge of a deposit at the exploration and planning stage, allow selection of the most appropriate and efficient mining method in a new area such that coal resource recovery is maximised in a cost effective manner. Current research and future requirements for research into mining methods and associated equipment and mine services are reviewed.

Jan 1, 1981