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By Y K. Leong

Iron ore tailings typically containing 40 to 50 per cent Fe can be beneficiated to iron ore products containing 54 to 60 per cent Fe. The impurities are comprised of clay, quartz, cristabolite and TiO2. Goethite and hematite are also present. At high concentrations of 55–60 wt% solids, the tailings displayed high yield stress and viscosity and cannot be pumped over long distances. Composite additives comprising of NaOH, phosphate-based additives and sodium metasilicate are found to reduce the viscosity and yield stress very significantly by a few orders of magnitude. The yield stress of 100 Pa can be reduced to almost zero. At this state, dilution of the tailings with its process water to 40 per cent solids causes the coarse and high-density iron ore particles to separate from the colloidal fractions located in the supernatant after a few minutes of sedimentation. Separation by decantation produces a sediment with an Fe content of 54 per cent from tailings with 47 per cent Fe. Another tailings sample with 48 per cent Fe was beneficiated to greater than 57 per cent Fe using NaOH-metasilicate-polyphosphate additives and employing an additional washing step. The use of other composite additives, NaOH and polyphosphates, increased beneficiated product Fe content to greater than 60 per cent from the same tailings. With the current iron ore spot price of more than US$180 per tonne, the cost of this treatment process even including a desalination step, if necessary, is relatively insignificant. This study has given tailings an economic value that should be exploited as soon as possible.

Nov 8, 2021

The society in which we live is one of change, and we professionals are part of that society. The importance of this simple and obvious statement is often overlooked. My Presidential Address examines the question: can professionalism survive in our changing society?There is ample evidence to show that our society is changing, and that the rate of change is exponential. This rapid and accelerating rate of change is what Alvin Tomer refers to as "future shock". Rapid change means that we do not have time to become accustomed to what is happening around us and to feel comfortable with it; the greater the rate of change the greater the discomfort. The effect that this has on people is varied; the change may be either expected or totally unexpected.The rate and extent of change in society is not the same for all countries nor for all industries or occupations. Change is more rapid in Japan, Korea or Taiwan, than in Australia. It is more rapid in our cities than in the bush, more rapid for professional businessmen than for farmers. In our minerals and petroleum industries, we are still adjusting to the great changes that have taken place over the last fifteen years. In the past, products from our industries were sold on a free and open market. Today, mineral development and production in most undeveloped countries and some developed countries is manipulated for political, social and economic reasons. Changes of this nature have had a devastating effect on the operations of established mineral producers in the democracies.Because of the accelerating nature of change, we must recognise that the past is not a reliable guide to the future.Although extrapolation of the past into the future is a basic ingredient of commercial survival, extrapolation is less and less reliable.I borrow from others in quoting the Irish proverb: "The future is not what it was".The future is where our business lies and most of us at this Conference must endeavour to understand it and adjust to it. I believe in the old adage that:You can't know where you're going if you don't know where you've been and where you are at.There are a number of major factors which have created change within our social, economic, and industrial environment in recent years.

Jan 1, 1985

This paper examines the broader implications of recent and ongoing changes in mineral resource managementå and reporting practices and the impact that these might have on mining companies. It is likely that an International Reporting Code will be developed in the near future, based on a number of National codes produced in recent years. However, this is only part of the reporting story, as an International Code brings with it a range of further issues to resolve. For the Code to be effective, there needs to be international recognition and perhaps licensing of Competent Persons and an expanded base of sponsoring professional bodies. Also, in an increasingly global business, shareholders, regulators and other interested parties need to know and understand the general processes involved in resource and reserve estimation and reporting in order to recognise companies that maintain the highest standards. There is a current trend towards greater scrutiny of company performance in a range of areas under the banner of corporate governance, and many changes are happening that will place greater disclosure burdens on all companies in the future. Good corporate governance means management of company assets for the benefit of the stakeholders. For a mining company, there is no greater asset than its mineral resources and reserves and directors are just as responsible for effective management of their mineral resources as they are for financial good practice. The paper looks at the relevance of corporate governance principles to mineral resource management and the changes that this could bring to the way that companies deal with regulators, shareholders, financiers and others. Finally, increased scrutiny and further regulation inevitably means greater effort by the industry and higher costs. Despite this the author believes that there are substantial offsetting benefits to be gained by companies prepared to take the initiative in improving resource management practices and communicating these improvements to shareholders. In order to achieve the benefits however, the industry needs to fully engage in the changes that are taking place û setting its own standards and working with the regulators rather than sitting back and being legislated against. Mineral resource reporting provides a good model of how this process can work and there will be other opportunities in the coming years as the industry seeks to develop best practice in mineral resource management. The author is an employee of Rio Tinto but wishes to point out that the views expressed in this paper are his own and not necessarily those of Rio Tinto.

Jan 1, 2002

By P Hawkes

Within the mining industry computers have made their most significant impact with 3D design, visualisation and resource modelling/ optimisation. Recently, the application of computers to data gathering and accounting functions has also started to reap benefits. These two areas of application cover the beginning and end of the mining process. There has been limited use of computers on the middle section, the actual mining process. This is interesting when considering the relative proportion of overall mining costs that this section produces. There is a certain amount of irony in the lack of mining application software for developing accurate budgets compared to the systems/software then used to review performance against budget. Computers have been used extensively in the manufacturing industry to design, model and simulate the manufacturing process. This has not been extended to the mining process. But, we all strive to have an open pit that replicates a manufacturing plant û smooth, efficient, optimal production. If we could model mining operations with the confidence of plastic box makers we would reduce risk by an order of magnitude, improve planning and focus on value drivers. Cost û benefit analysis would be easy. The extrapolation of manufacturing to mining process models is difficult. The variables in the manufacturing process are fewer in number, have low volatility and are highly predictable. The time between a box falling on a conveyor belt and falling off is very consistent. Mining is quite the opposite. It has large numbers of variables, some of which are unpredictable and volatile. The time to fill an excavator bucket could vary by 30 per cent and the frequency distribution is unlikely to be a mathematically simple normal distribution. Further, each of these variables can be distorted by one-another û they are interrelated. The mining process is a disjointed flow of parcels whereas manufacturing is a controlled continuous feed. A loaded truck might join a ramp and follow a slow water cart up. This is the equivalent of a localised voltage drop on equipment in a manufacturing plant. The manufacturing plant is quite likely to rapidly recover to full capacity. Whereas the slow truck might throw the mining fleet cycle out of balance for hours û trucks queuing at the ROM bin and so on. A mining process simulation has been created that addresses these mining variable issues to produce a highly accurate model of the open pit mining process. The number of uses for such a model is growing rapidly as it is being utilised for a variety of projects within the industry. This paper discusses the need for and application of mining process models.

Jan 1, 2003

Mineral exploration and development can have a significant impact on the environment and local communities, in some circumstances extending well beyond the mine site. Poor environmental performance and consequent social impacts by some companies have affected the reputation of the whole industry to the extent that the principal public concern about mining is its impact on the environment. This is consistent with public attitudes about other major natural resource sectors such as forestry and commercial fishing. Traditionally the community has relied on governments to set the benchmark for acceptable environmental and social performance through establishing and revising regulations governing the mining industry. This however assumes that regulations keep pace with community expectations. It also does not take into account those circumstances where governments can have conflicting roles as both watchdog and project partner. Government regulations and industry self-regulation are not in of themselves sufficient for the minerals sector to demonstrate that it has adequately addressed environmental and social issues associated with the sector. For the minerals sector to improve its reputation it must first improve its environmental and social performance. To do this requires the sector to operate to acceptable standards of environmental and social performance and for the sector to be able to credibly communicate this to its stakeholders such as investors, non-government organisations (NGOs), customers, staff, regulators and local communities. Independent third party certification of environmental and social performance (æcertificationÆ), already operational in forest and fisheries management, is proposed as a mechanism to enable the minerals sector to achieve this. World Wide Fund for Nature (WWF) and industry partners will be collaborating in a project to ascertain the applicability of æcertificationÆ to the minerals sector. A number of economic, social and environmental benefits are identified that could accrue should mining companies be able to differentiate themselves on the basis of environmental and social performance, an attribute evident in æcertificationÆ schemes. External audiences are seeking increasing levels of information and data on environmental and social performance of mining companies, be it local communities, investors, financial institutions or NGOs. Environmental and social reporting should be a key communications device that stakeholders can rely on as a reliable, credible source of information on environmental and social performance. WWFÆs contribution to the debate about environmental and social reporting has been to develop a process to assess the quality of environmental and social reports against reporting ingredients which WWF believe are important if a report is to be an accurate reflection of the reporting entitiesÆ environmental and social performance.

Jan 1, 2002

Address by the President (Mr B T Loton) in presenting the Institute medal for 1981 to Charles Wooller Marshall AO. Address by Charles Wooller Marshall AO after accepting the medal.

Jan 1, 1982

By S Pigram, G J. Jameson

This paper is concerned with the tracking of particles in the froth phase of an aerated water/glycerol mixture. Experiments have been carried out in a specially designed laboratory flotation cell that allows formation of a deep froth. Phosphorescent tracer particles of various sizes were injected into the centre of a froth column where they were excited by ultraviolet lights, positioned at the back and front of the column. The motion of particles was captured on a digital camera with a green filter. The images from the digital camera were then transferred to a computer and an image analysis program was used to convert the colour intensity to the concentration of particles at each location within the froth. The tracer technique was used to determine the dispersion of hydrophilic particles and the variation of the concentration of solids with axial and radial positions.

Jan 1, 2005

During the past seven years silver recovery has been increased from 9 per cent to over 61 per cent. The changes in plant practiee which have led to this increase are described. Gold room clean-up procedure has been varied, so that half the additional silver is obtained as pure silver chloride, which.is converted to silver bullion for marketing.

Jan 1, 1964

The title of my address today is "Oil and Gas Valuations - A Simplistic View of Some Critical Issues". Alternatively I could have called this address "Pitfalls for investors' and corporates in accessing Independent Experts Reports" 'as in this brief 12 minute talk I will briefly comment on some common misconceptions with regard to the valuation of exploration areas and production interests, and comment on how the draft release guidelines address these issues.

Jan 1, 1989

A recently discovered high temperature (22G-2800°C) reaction between glycerol and the oxides and hydrous oxides of iron produces a green, well-crystalline complex glycerato-iron, whereas hydrous nickel oxides an) reduced by the glycerol to metallic nickel. When nickel isomorphously substitutes for iron within the goethite lattice this high temperature glyceration allows a separation of the two metals whereby the nickel can be extracted by solution techniques.

Jan 1, 1971

INDEX OF CONTENTSIntroduction.Systems of classification of coals.RankClassification of Australian coals.Defects of systems in use in other countries.Indexing by Fuel Ratio.Classification by Ultimate Carbon/Ultimate Hydrogen.Relationship between Fuel Ratio and ultimate composition.Suggested convention for classification.Origin and Evolution.Notes on directions of change of composition on Carbon Hydrogen chart.Summary and conclusion.Acknowledgments.Bibliography.Appendix.

Jan 1, 1948

Although the 'exi'stence of bauxite in Australia has been known for many years it is only recently that exploitation has commenced.. of the two most' important` deposits, strangely at almost diagonally opposite tips of the continent. Recognition of the importance. of the bauxite in the South/West corner came about initially through the efforts of a well-known Australian mining company which,` with some outside financial help, tackled the early exploration with commendable foresight and courage.

Jan 1, 1964

By Wickham P

Digital computer based control systems are used to implement control and monitoring over most unit operations in Mount Isa Mines Limited lead-zinc concentrator and copper concentrator. Implementation has been gradually devel- oped and expanded since the first process computer installation in 1969. Operations currently using high level control logic include crushing, grinding, on-stream analysis of flotation products, flotation reagent additions, and tailings thickening. Details of gains in metallurgical efficiency for each system are considered.

Jan 1, 1978

By Buizen M, Eagleton A. C

The results of calibration trials conducted on parachute stoppings both overseas and in Australia under a recently completed NERD&DC grant, are presented. Applications of parachute stoppings, for rapid regulation and control of ventilation networks are described including use in blasting areas and rescue work. Several parachute-type stoppings are described and their applications Investigated

Jan 1, 1988

By Sinha NH

ICI Australia and CSIRO have developed a novel process for extraction of zirconia from zircon sands. The two stage process involves a high temperature step and a wet chemical processing step. A pilot plant has been operating since November 1985 at CSIRO Division of Mineral Chemistry, Port Melbourne and construction of a full scale plant isplanned at Kwinana, WA.The plant has a high degree of flexibility and is capable of producing high purity zirconia up to about 99.99% and withinspecific particle size ranges. The products are being marketed by the joint company, 2-TECH Pty Ltd.

Jan 1, 1986

By Conley R, Payne I

The Vickery Coal Mine commenced open cut mining operations in May 1991. All overburden and interburden is drilled and blasted for excavation by dragline or hydraulic excavator. The mode of operation adopted from the feasibility studies requires that throw blasting of the overburden be used to assist dragline productivity.This paper reviews the development of the drilling and blasting practices with particular emphasis on the throw blasting of the overburden and optimisation of costs. This review includes analysis of the pre-production drilling and blasting feasibility studies by comparison with actual results.

Jan 1, 1992

Petroleum exploration is proceed ing in Western Australia at an ever- increasing pace. Results in recent years have been very successful, with the discovery and development of the Barrow Island oilfield and the Dongara gasfield, and the discovery of several major gas-condensate fields on the Northwest Shelf. The Northwest Shelf discoveries will have a big impact on the economy of the State by providing an abundant indigenous source of energy. Prospects for further large dis- coveries are believed to be excellent. The most prospective areas are thought to be on the continental shelf in the Carnarvon, Browse, Perth, Canning, and Bonaparte Gulf Basins.

Jan 1, 1973

The word `environment' may have many different meanings but, for the purposes of this paper, I have assumed the definition included in the Environmental Protection Act 1986 (Western Australia). This Act defines `environment' as `... living things, their physical, biological and social surroundings, and interactions between all of these'. The Act further defines the `social surroundings of man' as `... his aesthetic, cultural, economic and social surroundings to the extent that those surroundings directly affect or are affected by his physical or biological surroundings'. This gives a very broad meaning to the idea of environment and environmental issues, and it is therefore understandable that the influence that environmental issues have on mining activity can vary so much from state to state, and even within states, and why the degree of influence can change so much with time.

Jan 1, 1990

Eleven years ago I addressed delegates to the Whyalla Meeting of this Institute on the subjects 'Oil in Australia?' -- a title which was followed by a large question mark.My purpose at that time, which was before Rough Range, was to interest members of this Institute in the possibility of oil in this country because I considered that exploration for mineralwealth was our concern.I doubt if I made much impression.but.I recall that the Chairman at that Meeting, Mr Ian McLennan, asked me pointedly to name the areas I-would select and I nominated the Northwest of Western Australia,'Gippsland and the Roma District

Jan 1, 1962

By Lovett EP, Johnson CR, Dunlop GA

Seven streams of a low tonnage pilot plant operation on Cu/Pb/Zn ore from the Golden Grove Project were continuously assayed using an AMDEL In-Stream Analysis (ISA) system. The ISA instrumentation is briefly described as is the calibration procedure employed. The successful application of this instrumentation in the dynamic environment of a pilot plant operation is discussed. The operational sequence of the Golden Grove pilot plant is outlined along with the original project objectives and how they were achieved by the implementation of ISA. Results for the different complex flowsheets used are discussed, followed by the perceived benefits of installing such equipment in this operation.

Jan 1, 1986