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Integrated chemical thermodynamic software and computerised databank systems have evolved over the last 15 years. The extent to which these systems have automated thermodynamic calculations relevant to extractive metallurgy is examined. The scope for further automation and the role of the expert consultant is discussed.

Jan 1, 1991

By Kuster D

Under humid conditions geochemical exploration for rare-metals is, at the reconnaissance level,usually carried out by stream sediment and soil sampling. As the secondary dispersion patterns are distinctly different in arid environ- ments, other exploration methods have to be applied (MATHEIS & KOSTER, 1985).

Jan 1, 1988

How many of you have felt tired and light-headed after standing or working in the sun or by the oppressive, hot, muggy conditions of an Australian summer? For those of you who have, you've experienced the minor effects of heat stress. Heat

Jan 1, 1994

This paper outlines some of the recent developments in Spiral Concentrator design, with particular reference to the range of Reichert spirals supplied by Mineral Deposits Limited, typical applications, and test or operating data, are also provided for the different series of spirals now available.

Jan 1, 1978

By Reeve JS

Heap leaching is a low capital cost alternative to conventional processing techniques for gold recovery from areas that contain small gold particles in a porous host rock.For successful heap leaching the ores to be leached must maintain good permeability after being stacked into heaps so that the leach solutions can percolate evenly through them.The presence of clays, slimes or excessive amounts of fines can hamper the flow of leach solutions causing channelling and producing dormant or unleached areas within the heaps. This results in unreasonably long leach periods and poor extractions. In extreme cases the clays or fines completely seal ore heaps, causing leach solutions to run off the sides of t'he heaps rather than penetrate the ore.The Northern Queensland Company uses the Agglomeration Heap Leach technique (AHL) to overcome the difficulties associated with clays or fines. This technique involves cementing the fines, by using readily available binders, into a rigid, porous network that greatly enhances uniform flow of cyanide leach solutions through the ore heaps.

Jan 1, 1986

The Honourable Tony McGrady, Queensland Minister for Minerals & Energy and our local member; the Deputy Mayor of Mount Isa, Alderman Bob Moore; members and guests of the Australian Institute of Mining and Metallurgy; Ladies and Gentlemen; welcome to the Carpentaria and Mount Isa Region Development Forum.Withoutdoubtwearein an exceptional placeatan extraordinary time. In this region we have a numberofexistinganddeveloping mines, plus several major deposits in pre-feasibility oradvanced definition stage, and we continue to see further vigorous exploration. All this mining industryactivity is occurring against a backdrop of wider political, social and economic change, affectingmostofAustralia. The North West Queensland Branch of the Institute decided that the time was ripe for an open forum where issues involved with developing the region's assets be presented and discussed between members of the industry and also the general public.That then is the aim of this meeting: it is to be a place of learning and discussion about issues relevantto the developmentofthese deposits. To this end feel free to use the microphones in the aisles at question time to direct your questions to the speakers.

Jan 1, 1993

The Liddell longwall equipment consists of 118 four leg supports, a shearer and armoured face conveyor of 170mm length. The equipment was supplied to Coal & Allied Operations Pty Limited (Coal and Allied) by Westfalia Australia Pty Limited (Westfalia). The project commenced as a feasibility study in 1983, a proposal was put to the board of directors in March 1984 and a specification distributed. Nine companies tendered for the supply of a longwall face and the supplier was selected from a short list of four companies. At the same time Coal & Allied examined the facilities at Liddell Colliery and decided to upgrade the conveyor belt system to cater for the high production from a longwall face. The surface facilities, transport system, water and electrical supplies to the colliery were also to be upgraded. During the twelve months to December 1985, the colliery was upgraded while the longwall equipment was being manufactured. The manufacturing process involved roof support testing, compatibility testing and finally a build up of 40m of longwall face

Jan 1, 1986

The paper discusses the use of animated dynamic numerical simulations to support design and operational decisions in the mining industry. The basis of the simulations discussed is a queuing theory engine with added features that enable continuous processes to be included in simulations. This approach is well suited to the needs of the mining industry which has a mixture of discrete events interfaced to a variety of continuous processes via various forms of surge capacity. Examples are given of the benefits of animation in communicating concepts to those with limited domain knowledge and simulation as a tool that facilitates the sharing of understanding between the stake holders of a system. The analytical content of the paper addresses conflict for resources within systems, the constraints imposed by human and other types of resources, and the impact of external events. Examples are presented showing the use loop diagrams and Gantt charts in the recognition conflict, and its causes. and the use of utilisation logs to identify opportunities for cost reduction.

Jan 1, 2009

By Lindbeck K

The mining industry in Western Australia is a large sector of the WA economy providing $12 billion (1993) of the export income for the State. Historically, mining in WA developed from traditional prospecting in the late-1880s leading to major underground operations by the turn of the century. Large open pits were developed in WA following World War II and became increasingly common since the gold boom of the 1980s. With the development of the open pits has been concomitant evolution of mining legislation, principally the Mining Acts of 1904 and 1978, which has been also accompanied by a practical evolution of the administrative system within the Department of Minerals and Energy. The mining industry has recognised the need for sound environmental management at mine sites, taking up the challenge and becoming a world leader in rehabilitation techniques. Any environmental management program in the industry has three stages: approval by government; management by the industry; and return to the State in an environmentally acceptable condition. The WA environmental requirements, procedures and industry performance in these three stages are discussed.

Jan 1, 1994

I am honoured, deeply honoured, that so distinguished a group has assembled to acknowledge the signifi- cance of the work of my Melbourne flotation research laboratory, to review progress since Principles of Flotation (Wark, 1938) was published, to highlight the present state of knowledge, and to point the way for future research. The flotation research which began in 1929 was sponsored by a group of mining companies2 at the instigation of Harry Hey of the Electrolytic Zinc Company of Australasia Limited. There were never more than three of us work- ing in rather cramped conditions in a laboratory made available by the Department of Chemistry at the Uni- versity of Melbourne, but what we lacked in space was more than offset by a freedom unparalleled in indus- trial research in Australia at that time. I pay special tribute to my first colleague, Alwyn Cox; to my wife who worked with us for several years; and to Keith Sutherland who followed Cox in 1936. They were my sole colleagues up to 1938 when Principles of Flo- tation (Wark, 1938) was published.

Jan 1, 1984

The Argyle AK1 Pit has been operating and producing over 25 per cent of the worldÆs diamonds by volume for over 20 years. The mining boom in Western Australia is creating upward cost pressures to ArgyleÆs mining operation while the price received for its product remains flat in comparison to many other Western Australian commodities. This incongruity, which when combined with other circumstances such as the pit being close to the end of its mine life, a decline in head grades and a tightening in operational constraints caused by the pitÆs maturity, is causing the leadership team at the mine to utilise innovative strategies in order to ensure that the open pit continues to perform economically until its final closure in late 2010. The strategies that will be discussed in this paper are step change business improvement methods, localisation of the workforce, employment of Aboriginal people and the use of a clear and concise consultation process in order to provide certainty to a workforce working in a pit during boom times where pit closure is imminent.

Jan 1, 2007

By Twemlow GL

The accounting profession in Australia and overseas has taken up the responsibility of setting standards specifically relating to the minerals and energy industries. Australia led the way with AAS7 Accounting for the Extractive Industries. This statement was issued in 1976 and amended 1977..It largely deals with accounting for preproduction expenditure and uses the term "economically recoverable reserves". It does not require disclosure of reserve quantities or values in balance sheets or as supplementary information in financial statements. The United States accounting profession in 1982 finally resolved an accounting standard in the same area as AAS7-SFAS69 Disclosures About Oil and Gas Producing Activities. It applies only to oil and gas producers, but has extensive disclosure requirements, including proved oil and gas reserve quantities. Current developments indicate that Great Britain is about to follow the US example. At this time in Australia, AAS7 or some other statement relating to the extractive industries has not been issued as an approved accounting standard by the ASRB. Standards issued by the ASRB are binding in law.

Jan 1, 1987

Economic and environmental pressures are shifting the world balance of titanium dioxide production away from sulphate based. manufacture towards the more cost effective and cleaner chloride route. In the chloride process for titanium dioxide pigment manufacture, TiOz and other metal oxides in the feed ore are reacted at high temperature with chlorine in the presence of carbon. These gases are cooled after they leave the reaction zone, upon which solid contaminants precipitate and are substantially removed. The liquid titanium tetrachloride is purified by distillation before again being vaporised and interacting with hot oxygen to form pigmentary titanium dioxide and regenerate chlorine for recycle. The base pigment is wet milled, surface treated (by coating with hydrous oxides of silica, alumina and others) and redispersed before packaging. Optical properties of TiO2 pigments are reviewed and the role of refractive index and particle size explained in brief. Pigment related factors affecting the opacity, colour, undertone, gloss and durability of coatings are examined with respect to manufacturing requirements. The superior performance of chloride based pigments is briefly reviewed.

Jan 1, 1991

By S M. Mousavi

The issue of estimating evaporation in soils is central to the design of engineered soil caps for mine waste and landfill applications. In general, because evaporation from the soil is difficult to measure in the field, laboratory experiments and empirical methods have been used. Much of the earlier work has been conducted in soil science, although in recent years, geotechnical and geoenvironmental engineers have given great deal effort to this work. The result of this increased interest is the development of numerical models, such as UNSATH and SoilCover for estimating evaporation. In this study laboratory-measured evaporation from soil columns was compared with evaporation predicted using the computer program SoilCover, and the analytical method proposed by Gardner and Hillel. Good agreement among the results was observed. Also the sensitivity of the predicted evaporation to soil hydraulic and geotechnical properties, such as saturated hydraulic conductivity and coefficient of volume change was discussed and the practical implication of the sensitivity were highlighted. The work has application in the design and construction of soil covers over sulfide-bearing mine waste and landfills.

Jan 1, 2003

By Muir DM

In recent years, significant improvements have been made in the design and operation of carbon-in-pulp plants. Some of the major developments in plant operation and technology are reviewed together with an outline of the research being undertaken in Western Australia. The main problems facing operators include the understanding and control of carbon fouling and regeneration, and the recovery of gold from the carbon. It is shown that carbon fouling by a variety of agents, particularly cyanide, calcium carbonate and silica, cause a significant loss of kinetic activity which in turn leads to poor plant performance. The importance of acid washing and adequate thermal reactivation is discussed. Although the Anglo elution procedure is commonly used in South Africa its use in Australia in preference to the conventional Zadra elution procedure is likely to be re- stricted because of its demand for high quality water. Solvent elution by the recently developed Micron procedure using refluxing methanol, ethanol or acetonitrile vapours is an attractive alternative. This elutes gold in 4-6 hours and provides concentrated gold solutions suitable for simplified gold recovery steps.

Jan 1, 1984

By D Curry, M F. Young

æConventional wisdomÆ believes that fine particles have low flotation recoveries. Plant size û recovery graphs often have the classic æhillÆ shape û high recovery in the mid sizes and low recovery at the fine and coarse ends. Yet if mineral liberation is poor, low fines recovery may be because you don't grind fine enough! This apparent paradox is explained by the old concept of æsand/slimesÆ circuits, which recognises the different flotation needs of fine and coarse particles. This concept is overlooked in the push for simpler circuits and larger equipment. Most plants now treat all particles together in a wide size-distribution. Reagent conditions are set for the dominant coarser particles, so fines are starved of collector. Worse still if there are significant midsized composites û often these have to be rejected in cleaning to achieve target concentrate grade. But the conditions which reject mid-size composites û collector starvation and high depressants û also reject fine liberated particles. In fact, fines flotation can be excellent when flotation chemistry is tailored to fines.

Jan 1, 2004

By A Benedictus, A Butcher, J Wikstr÷m, B Lindblom, E Rutqvist

LKAB is a mining company situated in northern Scandinavia, manufacturing blast furnace- and direct-reduction pellets and sinter fines. Pellet development at LKAB comprises testing at laboratory and pilot scale. The LKAB Experimental Blast Furnace (EBF) is a unique test facility and an important tool in terms of product development and process research. For a better understanding of pellet behaviour in the blast furnace process, LKAB has started to use automated mineralogy for the characterisation and quantification of its iron ore products and pellets. A mineralogical evaluation of iron ore olivine pellets, taken from a test campaign in the EBF, has been performed. The studied materials were samples from excavated pellet layers through the entire EBF at different positions. A large number of iron ore pellets was analysed using a combination of automated mineralogy, using QEMSCAN«, and chemical analysis. Important information about the performance of pellets in the blast furnace process, such as a quantitative description of mineral and iron oxide alterations at different temperatures, Fe-reduction and alkali deposition, was obtained.

Jan 1, 2008

In underground ore mining of copper ore, lead-zinc ore, tin ore and fluorspare in German Democratic Republic geological situation is characterized by ore deposits of small thickness and great variability of ore grades and mining conditions. For long range mining strategy and short-term planning of production a model was developed fitting to make optimal economic mining decisions. Starting point of the model is a cost function representing all direct costs per unit recoverable metal in concentrate for each stoping unit (ore reserve block). In the costs function the results of regression analysis of ore grade and metal recovery in concentration plant were considered. All stoping units (ore reserve blocks) of a mine were arranged to growing direct costs. The relationships of recoverable metal, ore tonnages and corresponding costs were plotted in a diagram. The data processed by- computer and the graphic representation of the results make possible 1. economic evaluation of stopes and ore reserve blocks, 2. estimation of cut off grade, 3. optimization of works planning.

Jan 1, 1977

In an earlier paper(l) details of a laboratory method of extracting and separating tantalum and columbium oxides from tantalite have been given. In view of the fact that Australia may have need to be self sufficient in this field it was decided to erect a pilot plant for the production of tantalum oxide in the Metallurgy School, University of Melbourne. The plant was designed for treating about 40 lb. of ore in a batch over a period of two weeks, although; because of the sectionalized nature of the process, the capacity of the plant was 40 lb. ore per week.Australia is fortunate in possessing some very rich tantalite and columbite deposits, particularly in the Pilbara District in Western Australia. The ore used in this work was obtained from a small but high grade deposit near Greenbushes, Western Australia, and consisted of lumps, weighing up to 8 lb. each, of almost pure ferro-tantalite with occasional thin veins of the very' rare' mineral stibiotantalite.The main constituents were:

Jan 1, 1946

IA )W cli',hla cn1cnt fault 7011(-s 0 11Cn cOrnprise a nrc,II of inrcIIinkc(I faults, cvtcnqonal shear and In]rck cxtcnsir>nal vein- fractures. Hydrothermal mineralisation localised around such structures testifies to their importance as conduits for fluid flow. Mesh structures are most commonly developed in situations approximating bulk pure shear but predominantly simple shear meshes also occur. They appear to develop through the infiltration of pressurised fluids into a heterogeneous rock mass with varying material properties. In some circumstances, mesh formation appears to be a precursor to the development of major throughgoing faults. Mesh formation generally involves hydrofracturing (Pf> a3, at least locally) and the condition Pf - 63 to be maintained for the mesh to remain a high permeability conduit, requiring fluid overpressuring at other than shallow depths in extensional-transtensional regimes. The volumetric character of earthquake swarm activity appears to result from the passage of hydrothermal fluids through mesh structures, representing a form of distributed fault-valve action along suprahydrostatic hydraulic gradients arising from magmatic intrusion, compaction overpressuring, metamorphic dewatering, etc.

Jan 1, 1995