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Safety bulletins and stickers issued for the paste backfill plant at Cannington read as follows: æCannington Paste Fill Plant, First of ItÆs Kind in AustraliaÆ. We could even dare to state that the Cannington plant is different than any other paste backfill plant in the world because of the overall design, plant equipment and underground delivery. However, one thing to be certain of is, the paste backfill plant works as designed and a pump is not required to deliver paste underground given the general plant arrangement at Cannington. The past two years have been a process of evolution to design and construct the plant and make it work. This paper will describe the paste process using full mill tails along with placement of cemented paste underground. Discussions will include rationale of fixed plant selection along with various control requirements. BHP World Minerals recently commissioned its paste backfill plant in December 1997. Cannington is placing full mill tails underground via two surface boreholes that deliver either to primary or secondary stopes.

Jan 1, 1998

By Heinrich CA, Wall VJ, Walshe JL

The Porgera Gold Mine, located in the highlands of Papua New Guinea, has produced over 5 million ounces of Au, since its opening in late 1990. The deposit is located within Upper Cretaceous Papuan Platform sediments approximately 25 km south of the Lagaip Fault, and is spatially and temporally associated with the 6 Ma alkaline Porgera Intrusive Complex.

Jan 1, 1995

By Houchin MR, Jenkins DH

This paper examines the importance of processing to the properties and performance of high purity zirconia ceramics. Many of the principles discussed, however, apply to ceramic processing in general. For fabricated ceramic articles to display their wide range of high performance properties, they must be made fully dense. The precursor powder and postpowder processing requirements necessary to achieve full density in the fabricated body are discussed. Brittleness, the anathema of ceramics, can be overcome in zirconia by incorporation of toughening mechanisms. Transformation toughening and microcrack toughening and their origins in partially stabilized zirconia are reviewed.

Jan 1, 1989

Industrial minerals and rocks (alternat ively called non-metallic minerals) are those- which are economically important because of their desirable physical or chemical properties rather than their metal or energy content. They are divided into nine classes: structural, pig- ments, process aids, ceramics and refractories, chemical source minerals, abrasives, foundry minerals, gem stones, electrical minerals. Development of deposits is influenced by the dominance of marketing,by the required range of products, the-need for specialized process- ing, place value, and the transportation and distribution of high-bulk, low-cost commodities. Evaluation is different from that of base metals because of differences in geological occurrence, sampling methods, testing, treatment, placing a money-value on the material and the importance of export markets.

Jan 1, 1973

DR. WARK, said: I have not come to Broken Hill to tell you how to conduct flotation operations; indeed, during my short stay here I have already learned much concerning the process, of the many difficulties which have been overcome, and of those still awaiting solution. My purpose to-night is rather different. All who have been concerned with the operation...

Jan 1, 1933

By K E. Barns, P J. Sharman, S A. Thomas and

This paper presents the development of a regrind facility design at BHP BillitonÆs Leinster Nickel Operations (LNO) in Western Australia. The recovery opportunity was identified from an analysis of plant operating data together with scanning electron microscope (SEM) measurements on relevant tailings streams from LNO. A laboratory procedure was developed to determine the potential recovery improvement of installing a regrind facility at LNO. The last step in formulating the process flow sheet and defining the process design criteria was to construct and operate a pilot plant, which incorporated four banks of flotation cells and an Xstrata M20 Isa Mill. Pilot plant on/off trials were used to define the expected metallurgical benefit. A prefeasibility engineering design and cost estimate was completed. Following a successful internal business evaluation, a feasibility study is currently underway.

Jan 1, 2007

By S Corbel, P J. T Donchak, W Gorczyk

The Hodgkinson Province numerical modelling project aims to develop an improved understanding of the physical conditions that lead to the localisation of goldbearing fluids within known systems and apply this understanding to the prediction of potential new sites of gold mineralisation. The project follows a series of stages from identifying the key parameters required to construct and test simulations through to reverse engineering of known deposits and ultimately applying the conditions identified in the preliminary stages to predictive simulations. Results of the modelling demonstrate strong geometric controls of the localisation of fluids during mineralisation. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

By Y S. M Tabatabaei, R Hosseini Tabata

Application of Acidithiobacillus ferrooxidans bacteria to flotation of Sarcheshmeh low-grade copper sulfide ore was studied. Sarcheshmeh low-grade ore contains pyrite, which causes some problems in the flotation of copper minerals. In this study, A ferrooxidans was used to change the surface chemistry of pyrite and copper sulfide ores and consequently, their flotation behaviour. In the presence of A ferrooxidans and xanthate as a collector, pyrite was depressed whereas chalcopyrite and other sulfide minerals were unaffected. In addition, the pulp pH remained unchanged. It was shown that the surface chemical properties of the bacteria could be manipulated successfully to achieve the desired effects in a flotation process. The results showed that the recovery of pyrite in the presence of the bio-depressant is 50 per cent lower than when no bacteria were present. At the same time the recovery of chalcopyrite remained unchanged.

Jan 1, 2004

By Thompson P, Sharma Y

The paper describes the methodology and results from a study carried out by Telfer Gold Mine to optimise the materials and costs involved in construction of the pad for their dump leach operations. The investigation involved large-scale field testing of five different types of liner and a number of different cushion and drainage layer configurations. The aim was to identify the most cost effective construction methods to allow the final dump height to be increased from 45 in to 60 in without causing significant damage to the liner. The effects of dump height on permeability were also investigated. These methods are described and results presented. The findings indicated that modifications to the existing liner/cushion layer/drainage layer configuration used previously at Telfer would actually reduce overall construction costs rather than increase them despite an increase in overall dump height. Relative construction costs are presented.

Jan 1, 1994

In Australian collieries, solutions to the outburst problem must be implemented in a highly competitive environment which has a low tolerance on negative productivity effects. Solutions are only applicable if the overall viability of the operation remains sound. Minimum time must be spent on alleviation and control measures. This is favoured by simple geology, advanced warning and efficient alleviation and control procedures. Research requirements in support of this include 1. an improved means of predicting the nature and location of outburst zones ahead of the face and, 2. an improved means of measuring the effectiveness of gas drainage. For additional safety at the face, a means of continuously monitoring outburst proneness is required. In general, greater emphasis is required on improved instrumentation.

Jan 1, 1987

A failure criterion for coal is proposed in which a distinction is made between brittle and "pseudo-ductile" failure. This criterion is then used in the development of new equations for coal pillar strength, including a transition from brittle fracture to pseudo-ductile yielding. In addition, equations are obtained which allow the äritical minimum pillar dimensions to be calculated to avoid "catastrophic" and "ultimate failure". The use of these formulae is then demonstrated by comparing the results with pillar case histories derived from the literature.

Jan 1, 1986

Nickel ores from three different mines, Digger Rocks, Cosmic Boy and Flying Fox, are treated at the Forrestania concentration plant. The ore types vary from oxidised supergene ores to primary pyrrhotite+pentlandite ores. Mineralogical investigations on the ore and process samples have been carried out in different stages of process development. One of the studies was done with the samples collected from the flotation circuit in 19 June 1994 when the Cosmic Boy ore was processed. The process products were screened, and the size fractions were analysed for the main elements by appropriate analytical methods. Mineralogy of the products was studied microscopically and composition of the sulphides was analysed with an electron microprobe. Liberation of the main sulphides in the flotation feed was determined with the point-counting method, and weight percentages of the minerals were calculated using chemical and mineralogical data. The typical sulphide assemblage of the Cosmic Boy ore is violarite, pentlandite, pyrite, pyrrhotite and chalcopyrite. Violarite dominates over pentlandite (ratio being 70 per cent to 30 per cent), and pyrrhotite is strongly replaced with pyrite and magnetite. One of the most common mineralogical features of this ore type is secondary magnetite, which occurs as narrow rims in porous violarite or in association with secondary pyrite. Serpentine, talc and chlorite are the main gangue minerals. In the milled feed (76 per cent -74 ¦m) locked particles between nickel and iron sulphides are common. About 41 per cent of total pentlandite occurs as pure liberated particles, and 33 per cent as locked grains with violarite. Liberation degree of violarite is 55 per cent, and the most common type of locked particles is violarite+magnetite, carrying about 20 per cent of total violarite. To achieve a recovery of 80 per cent for pentlandite, all the particles containing at least 50 vol-% pentlandite should be floated into the nickel concentrate. Correspondingly recovery of 80 per cent can be reached for violarite if all the particles containing at least 65 vol-% violarite are floated.

Jan 1, 1996

The operators of the iron ore railroads in the Pilbara faced problems of excessive wear between rail and wheels as the tonnage hauled increased in the early 1970's. Joint research projects were begun between Hamersley Iron, Mt Newman Mining and the BHP Melbourne Research Laboratories to study these problems and recommend solutions. The particular problems of wheel rail interaction were solved by asymmetrical profile grinding of the rail and modifications to the machining of the wheels. Rail materials were improved through increasing yield strengths by alloying and by heat treatment. Wheel materials were improved by alloying. The economic benefits of these improvements have been demonstrated by much reduced re-rail requirements and other reduced maintenance costs.

Jan 1, 1986

By S Latchireddi

Close circuiting autogenous and semi-autogenous mills is an energy efficient way of grinding and a number of operations have utilised this in the design of their comminution circuits. Owing to the large flow of slurry through the mill that results from operating this way the grates and pulp lifters have to be designed to cope. However, the literature has little or no information on how grate and pulp lifter size and design are related to their ability to remove slurry from the mill. Over the last few years the JKMRC has been researching this area and has developed relationships between grate/pulp lifter design and flowrate capacity. At the same time it has determined the major causes of pulp lifter inefficiency and a solution to preventing this inefficiency (the Twin Chamber Pulp Lifter). This paper describes the models that have been developed through this program and uses industrial scale data to illustrate their accuracy. Results from the industrial trials of the Twin Chamber Pulp Lifter are also presented.

Jan 1, 2000

By V Ser, I Smit, C Robertson

Anglo American has been researching the potential benefits of inter-particle comminution techniques for several years. Inter-particle comminution has additional benefits in terms of milling circuit performance such as energy consumption and stability. This paper focuses on the flotation benefits. Inter-particle comminution leads to selective breakage, mineralogical analysis has shown that this leads to improved liberation of the valuable minerals. In addition to selective breakage, the relatively short residence time experienced in typical inter-particle comminution machines allows more efficient classification which contributes to a æsharperÆ product size distribution. The effect of particle size in flotation has been well documented in literature. In general, it is has been shown that there is an optimal particle size range for flotation, and that both above and below this range, flotation recovery is adversely affected. Results show that the narrow size distribution which results from inter-particle comminution improves flotation recovery. Furthermore, the absence of excessive fine gangue material which typically results from conventional fine (-75 ¦m) milling of talcaceous ores, can lead to 100 per cent savings in depressant consumption when such ores are subjected to inter-particle comminution. To-date, this technology has been evaluated on more than ten ores. This paper will focus on one set of results which demonstrates a number of common differences that exist between material that has been milled conventionally and using inter-particle comminution technologies, with emphasis on what the impact of these differences is on flotation performance. A pilot scale (200 kg/h) vertical roller mill (VRM) was used to produce the material, and the results shown will describe conventional laboratory batch, locked cycle and pilot plant flotation testwork.

Jan 1, 2005

By J Abols, T Hughes

The selective recovery of gold and silver from solutions containing other metals, such as copper, is possible using AuRIX«100 resin in conjunction with the Gekko Resin Column. Selectivity is driven by controlling the solution pH, which enables activities such as loading copper, gold and silver and then selectively stripping copper before gold and silver. Alternatively gold and silver can be loaded and the copper left in solution. The selective loading of gold while reducing the silver loading has also been demonstrated, opening the possibility of producing high grade gold dorT from high grade silver pregnant leach solutions. This paper reviews the AuRIX«100 resin and Gekko Resin Column Technologies, discusses the uses of AuRIX«100 in the recovery of gold and silver and the chemistry relating to several projects for which AuRIX«100 is being tested.

Jan 1, 2005

By R Ashworth, S J. Hall

During trials which began in May 2005, traditional steel dump bodies for transporting iron ore on 220-tonne haul trucks at a Labrador iron ore mine were compared to a novel rubber suspended dump body. Loads were measured and compared over some 93 700 loads, representing more than 20 Mt transported. Maintenance costs and downtime were also measured over the course of the trial, which lasted nearly one year. This paper outlines the parameters and results of the trials. Parameters measured included payload and production improvements, carry-back reduction, downtime due to body maintenance, and wear on the floor of the suspended dump body. These parameters were then compared to those for conventional steel dump bodies in use at the mine, and conclusions were drawn. The resulting comparisons were significantly positive in favour of the new suspended dump bodies, confirming that each truck could haul an additional 41 000 tonnes per year, that downtime hours could be considerably reduced, and that body availability and service life can be extended through use of the suspended dump body. There was also a high level of operator acceptance of the suspended dump bodies due to less loading shock and a smoother ride.

Jan 1, 2007

By M J. Nugus, S C. Dominy

Mesothermal lode-gold deposits often pose problems during sampling because of their complex and erratic gold grade distribution, and the presence of coarse gold. Effective sampling and sample preparation protocols must form the basis of any resource estimate at whatever stage a project is at. Design of a sampling regime must be based upon a thorough understanding of orebody mineralogy and geology. This should include consideration of gold particle size and distribution. The sample type, size and density employed must also be based on the underlying geology of the deposit. Choice of sample preparation procedure and assay type is of critical importance if fundamental sampling error and analytical errors are to be minimised. Traditional fire assays, using small charge sizes, consistently understate assays gained from large charge sizes and techniques such as screen fire assay and bulk leach extractable gold assay. The proportion of coarse gold within samples will have a profound effect on the requirements for sample preparation and assay method. The application of Gy sampling theory can help to reduce errors within the processing of samples of broken rock. Quality control/assurance of sampling regimes must also be critically assessed. The problems associated with sampling mesothermal lode-gold type deposits are presented as case studies from Western Australia and North America.

Jan 1, 2003

Geomorphology is one of the most basic elements in geographic enviroments. Geomorphological mapping is significant in the spatial distribution of representing land form and understanding various features of geomorphology. Geomorphological mapping began very early in China, as the map, showing conekarst(karst pinnacles) of Juiyishan, Hunan province, it was drawn in 168B.C., which was excavated from Han tomb. Mawangdui, Changsha. Its original idea of map-making is rather similar to that of modern map and could undoutedly be the oldest map of tropical karst discovered in the world.Before liberation, landform mapping was done piecemeally and only a small number of maps were prepared by a few editor as insets.

Jan 1, 1990

I am sure that you are- all familiar with Airborne Magneto-meter Surveying so I shall-spend only a brief moment describing the instrument and techniques and the remainder of the allotted time-on-modern-application-of the instrument.The Airborne Magnetometer used by Aero Service in AUstralia-was designated by Gulf Research and implements the saturable-core flux-gate--principle. The first magnetometers developed'weremagnetic-balances and depended on the counter-torque principle but these required a stable platform and hence are not applicable to airborne surveying. Other methods include the induction methods, the Hall Effect methods, magneto-striction methods., Deflectioh. of,free.electrons, the proton-precession methods.Some: of these are applicable to airborne surveying. As a matter of-fact the nuclear precession magnetometer is the one generally used in the Satellites because it has been miniaturized most successfully.The Gulf Magnetometer is the one most generally used in mineral and petroleum exploration because its sensitivity is sufficient for the problem and-data and instrument techniques have been worked out and standardized.

Jan 1, 1962