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Flotation science and technology are related to three major sub- processes which are organized in a hierarchical structure as shown in Fig. 1. The basic sub-process is the chemical process which affects the attachment of air bubbles to mineral particles. In particular, the chem- ical process is related with the adsorption of surface active sub- stances at the gas-liquid, liquid- solid, and gas-liquid-solid inter- faces. This field has been most intensively explored in flotation research. The second domain in flotation research is concerned with the mineral particle to air bubble attachment sub- process in the system. This sub- process represents the dynamics of particle and bubble encounter where the contact angle and the induction time, determined by the surface chem- istry of the system, are among the most significant parameters. This sub-process can be referred to as the micro-process as against the third sub-process, or the macro-process, which corresponds to the integral behaviour of the system. Two other sub-processes are integrated into the macro-process in which they may not reveal themselves explicitly in the details. The third sub-process does not entail surface-chemical or physi- cal events any more, but it represents them all inclusively. To represent this sub-process we use mathematical equations, called models. Only in some simple or simplified cases can the models be solved exactly to find out the behaviour of the flotation system in which we are interested. Digital

Jan 1, 1984

By Beer G

The recent re-emergence of an Integral Pressure Stripping system which operates with both cell and column in closed circuit at elevated temperature and pressure, requires no cyanide in the eluate solution and has greatly reduced carbon reactivation requirements in seen as a progressive step in this area. Several of these re-configured IPS systems have been placed in service in Australia and overseas in the last three years, with the first of the new generation units constructed and commissioned by Como Engineers Pty. Ltd. at Mt. Fisher in the East Murchison of W.A. in September 1987. This plant was relocated to a new ore body at Darlot W.A. in February 1989. Use is made of a data base of raw plant performance figures from both Mr. Fisher and Darlot and its performance compared with other operating plants. Initial commissioning difficulties of the Mt. Fisher prototype and dis- cussed together with the modifications and operational procedures required to overcome these problems. Stripping times of less than 6 hours at 145 degrees have been achieved with barren carbon values less than l O ppm from loaded carbon values above 3000 ppm and with cell pass efficiencies reaching 90 per cent.

Jan 1, 1991

The Rosebery Mine on the west coast of Tasmania is a world class polymetallic base metal deposit, containing six major minerals: galena, sphalerite, chalcopyrite, gold, silver and pyrite. This resource has been exploited for nearly a century, yet a reliable estimate of the reserve continues to present a challenge.Over the past twenty years, the operation has changed from relatively low productivity cut and fill timber-support scraper mining, to higher productivity bulk mechanised open stoping. At the same time, economic constraints have changed and grades have fallen, which have increased the pressure to refine the resource/reserve estimating processes. This paper compares the restrictions of the polygonal section method of the past with the advantages of a kriged block model. The limitations of Mine Call Factors, the problems involved in converting decades of diamond drilling data on paper into a computer data base, and the effect of this new methodology at Rosebery, are described.

Jan 1, 1990

By Large RR

Underlying the 15 million tonne, high grade Hellyer volcanogenic massive sulphide deposit of western Tasmania is an extensive, well developed, and well preserved stringer system. Pervasive alteration of the footwall mafic volcanics occurred as the hydrothermal system initiated. Mineralogical zoning exists within the footwall alteration pipe, with a central siliceous core giving way to zones of chlorite, chlorite-carbonate, sericite-chlorite, and finally sericite-quartz on the margins (stringer envelope zone). However, the alteration morphology and zonation is not symmetrical around the central siliceous core; eastward the alteration zones are steeply dipping and terminate abruptly under the massive sulphide, while westward they extend out under the ore body in a blanket fashion. Geologic evidence indicates that the pervasive alteration started with the development of sericite-quartz which was subsequently overprinted by chlorite and finally quartz-sericite as the hydrothermal system became focused towards the centre of the stringer system.

Jan 1, 1990

By B Armstrong

The Proterozoic poly-metallic Trilogy deposit was discovered in 1997, and until recently, mining evaluation was stalled due to poor metallurgical performance. Unlocking the substantial economic value of the deposit required a coming together of geologists, mineralogists, metallurgists and mining engineers, who by working collaboratively, uncovered the detail necessary to allow the required metallurgical breakthroughs to occur. The deposit itself is described as a sedimentary exhalative (SEDEX), with an enriched lead-zinc-silver core surrounded by a broader envelope of copper-gold mineralisation. The geological domains were defined in broad terms based on the style of mineralisation, assay values and lithology. These domains, while adequate for the resource estimation process, failed to translate into representative metallurgical domains. Additional work with new techniques defined regions in the deposit with altered processing properties which could not be recognised by conventional geological logging. Such additional complexities could not be appreciated at the outset of the metallurgical test work program.These regions were defined by applying the EDTA analysis method for recognition of where the valuable sulfides, particularly galena, had been partially modified by oxidising conditions. Hence, the flotation response of the valuable sulfide minerals was diminished and the increased amount of heavy metal cations available in the system significantly reduced selectivity in the flotation process.Understanding the detail of this complexity was essential in determining representative metallurgical domains, which was the first step in the long road of development.

Sep 5, 2011

By Sharpin PC

The countercurrent gas-solid-heat transfer during the drying of brown coal briquettes in the pilot carbonization plant at Morwell has been analysed and theoretical gas and solid temp-erature distributions through the drier have been calculated. Although the calculations rest on several simplifying assump-tions, to be corrected as the experimental work develops, the theoretical temperature distributions compare well with those observed in practical operation. Valuable conclusions are reached as to the effects of changes in drier operating con-ditions on the rate of drying of the briquettes which-controls the 2 strength of the char produced. The analysis shows why a limitation was reached in the improvement of char-strength in the pilot plant in 1961 and a prediction is made of ' a way ' in ' which the limitation could be overcome.

Jan 1, 1963

By Stewart W. J

The volumetric method of estimating hydrocarbon resources and recoverable reserves is and probably will remain a dominant method in petroleum engineering. The method is technically very simple, but has one main problem: how to express, measure and properly handle the variable and complex uncertainty of each estimate. The computer age brought in the Monte Carlo Simulation method which enables correct arithmetic operation using data with specified probability distribution. However, several problems are still not solved uniquely and still exist. For instance, the determination and description of the distribution of single parameters, the determination of the degree of dependency between parameters (e.g. hydrocarbon saturation-porosity), and standard probabilist- ic definition of generally used categories (e.g. proved, probable, possible). Methods for handling these problems are discussed.

Jan 1, 1979

By Doyle P, Mulroney D

The Cassidy Shaft was sunk to access the Mount Charlotte and Reward Orebodies below the Flanagan Fault. The 1,184m deep shaft is concrete lined to 6.5m diameter for its full depth. The initial 590m was excavated by stripping into a 1.8m diameter borehole and hoisting the broken material through the existing mine. The remaining 594m was excavated by conventional shaft sinking methods. The shaft was sunk through 3 existing plats and an additional 8 plats cut. 1,800 tonnes of steel and 8 cables were installed during the furnishing of the 4 compartments.

Jan 1, 1985

By Taylor G. H

The proposed classification scheme is based on two primary parameters, one for petrographic composition and the other for rank, both being determined with microscopical techniques. The scheme has been applied to a wide range of Australian coals and found to provide a useful means of relat- ing their inherent properties to properties such as volatile- matter yield, crucible swelling number, and calorific value, which will determine how these coals might be used coimierciallyti,

Jan 1, 1969

The outlook for suppliers of energy to the expanding economies of the Pacific Basin region is essentially positive, but particularly for exporters of high quality steam coal. This paper argues that economic growth in the Pacific Basin region has exceeded world economic growth for some years and that this will continue to be the case for the next decade at least. It looks briefly at the link between economic growth and energy demand and at the relationship between energy demand and the demand for electricity.Changing preferences in fuel mix for electrical generation in the region are noted and tentative forecasts made about variations in this mix. The pros and cons of various forms of fuel used to generate electricity are considered from the point of view of the consumer.

Jan 1, 1990

By D Whitworth

The Golden Pig mine has embarked on a diamond drill program design philosophy that increases flexibility of the program by greatly increased drill pattern densities. The use of standard broad pattern diamond drilling at the Golden Pig mine has previously lead to operational inefficiencies and impacted significantly on the costs of the mine. The diamond drill program philosophy and its interaction with mine planning is explained. The case study of the E lode mining as used to internally justify the increased drill densities is detailed.

Jan 1, 2002

By Barber C, Buselli G

Detailed monitoring of point sources of groundwater pollution is expensive due to the high cost of drilling monitoring boreholes. Whether groundwater pollution is due to mining, industrial or domestic waste disposal, a universal difficulty when monitoring groundwater contamination is the placement of boreholes to adequately define the extent of the pollution plume. This paper reports groundwater 'resistivity variations determined from transient electromagnetic soundings at a domestic waste disposal site north of Perth in Western Australia. Together with available hydrogeological and water quality data, the geophysics provides a broad "plume scale" picture of groundwater contamination. A simple three dimensional model of plume development, which takes account of the dimensions of the wastes, has also been developed and shows good agreement with the spread of contamination indicated by the geophysics for relatively small values of the dispersivities. Better estimates of these parameters are still required. The work indicates that a combination of geophysics and modelling with ground-truth data from groundwater quality monitoring of boreholes is required to avoid difficulties in interpretation of data and to better define the extent and migration of pollution in Groundwater.

Jan 1, 1988

By S Wangchai, D B. Hastie, P W. Wypych, A P. Grima

Industries that handle and process ‘dusty’ ores are facing increasingly difficult challenges to ensure sustainable operation and development. Most existing dust-control measures treat only the symptoms of dust generation and do not deal with the root cause/s of the problem. Many of these methods are also relatively inefficient in terms of controlling dust emissions. This paper summarises the various existing options available for dust control and some of their features, advantages and disadvantages. It then describes some of the new technologies that are being researched, developed and employed to minimise dust emissions by addressing dustability or dustiness and the dust generation mechanisms found in industry. Recent research results and case studies are presented to demonstrate some interesting findings obtained from this work. With improved understanding and modelling of dust generation mechanisms and bulk material dustiness, it is possible to achieve a step-change improvement in the design, troubleshooting and application of more efficient dust-control technologies.CITATION:Wypych, P W, Hastie, D B, Wangchai, S and Grima, A P, 2015. Research and application of new dust control technologies for the iron ore industry, in Proceedings Iron Ore 2015, pp 529–536 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

A review is given of progress made to- wards the development of personal gravimetric dust sampling for risk assessment on South African gold mines. The present strategy is critically examined on the basis of principles for assessing health hazard from dust exposure. Reasons are advanced for replacing the konimeter with a gravimetric system based on full shift personal sampling. Constraints imposed by local characteristics of gold mines are used to illustrate the difficulty in finding suitable instrumentation for measuring personal exposure to respirable silica.

Jan 1, 1988

By M Zengerer

The Basil Cu/Co deposit comprises a 26.5 Mt Inferred Resource of copper and cobalt, grading 0.57?per cent Cu and 0.05 per cent Co. It lies in the Harts Range, Central Australia, within the Riddock Amphibolite of the Irindina Province. Analysis of drilling within the mineralised zone of the deposit determined a spatial association between pyrrhotite with high magnetic susceptibility and chalcopyrite, following a strong magnetic trend as determined from airborne geophysics. A study was commissioned to examine if geophysical inversion could predict the distribution of sulfide mineralisation based on pyrrhotite from drill hole intersections, as well as predicting further mineralisation at depth or in the vicinity of the deposit. Petrophysical and geostatistical analysis of drilling susceptibility and mineralisation provided a basis of property distribution inside the model. This was followed by 3D geological modelling of mineralisation based on domain kriging of drill hole susceptibility sensitivity testing of signal to source depth, and distribution was performed using 3D forward modelling. Stochastic inversion generated alternative 3D geological models, which were tested for behaviour and adherence to observed drilling data and geostatistical limitations using GeoModeller software. Predicted mineralisation distribution was compared with conventional geostatistical modelling and found to be in agreement in planar behaviour but exhibiting possibly isoclinally folded trends, with reliability increasing closer to the surface. Predictions of mineralisation at greater depth and beneath weaker anomalies were more diffuse due to small model cell size having limited influence on the signal at depth.The Blackbush uranium deposit comprises a 64.5 Mt Inferred Resource, grading 230 ppm U in the Pirie Basin south of Whyalla, South Australia. It directly overlies the radiogenic Samphire Granite and is considered a tertiary unconformity deposit. Sensitivity modelling was performed using high-resolution ground gravity to see if a deposit signature could be detected using gravity. This required 3D implicit modelling of the geology and mineralisation from drill hole data and characterisation of an associated physical property model using domain kriging in GeoModeller. Density models relied on exploiting an observed relationship between logged density and measured uranium oxide percentage. The residual gravity response of the background geology model identified the location of the uranium deposit. Stochastic inversion of the litho/property 3D model has refined the known distribution of uranium from drilling and provided structural insights into the deposit.These projects have become excellent case studies for exploiting the relationship between mineralisation and potential fields and for testing the applicability of using domain kriging of properties determined from drilling to build robust 3D geological models for stochastic geophysical inversion, leading to robust methods for exploration targeting and mineral deposit prediction.CITATION:Zengerer, M, 2014. Use of geostatistically-constrained potential field inversion and downhole drilling to predict distribution of sulfide and uranium mineralisation, in Proceedings Ninth International Mining Geology Conference 2014 , pp 281–290 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 18, 2014

By Mankosa MJ, Yoon R-H

A reliable scale-up procedure for column flotation must address three important areas of column design, ie column geometry, sparging system and wash water distribution network. The column geometry is dictated by the maximum froth carrying capacity (which determines column diameter) and the bubble-particle attachment rate and particle retention time (which determines column length). The most important factor in the scale-up of an air sparging system is the ability to produce small bubbles in both laboratory and full-scale columns. Other factors, such as energy consumption and maintenance requirements, should also be considered in the scale-up of bubble generators. It is also important to design a wash water distribution system that can properly control the froth stability and maximise the column throughput. Based on these criteria, a successful scale-up example is given.

Jan 1, 1993

By M I. Pownceby, N A. S Webster, J Manuel, N Ware

The properties of iron ore sinter – commonly defined by measures of tumble strength, reduction degradation and reducibility – have a major impact on blast furnace performance. These properties are largely influenced by raw material properties, in particular the bulk ore composition. Despite this importance, there is a lack of quantitative data on the impact of ore chemical composition on iron ore sintering. This is surprising since the levels of Fe, SiO2, Al2O3, P, MgO and other elements, together with the nature of the minerals in the fine ore, play a major role in determining the abundance and type of high-temperature bonding phases that form during sintering. It is the abundance and nature of the high-temperature bonding phase(s) that directly influences sinter quality. This study combines in situ diffraction experiments in model sinter systems with laboratory-based compact sinter tests using natural ores to examine the links between iron ore composition and sintering temperature and their effects on standard metallurgical sinter quality test methods. Results help to establish the critical compositional and thermal parameters that control the bonding phase chemistry, which in turn influences the physical characteristics of the sinter matrix. This information should enable operators to predict optimum sinter operating conditions based on the initial chemistry and mineralogy of the iron ore fines and recognise the chemical modifications to the original iron ore fines required to produce high-quality iron ore sinter.CITATION:Pownceby, M I, Webster, N A S, Manuel, J and Ware, N, 2015. Iron ore geometallurgy – examining the influence of ore composition on sinter phase mineralogy and sinter strength, in Proceedings Iron Ore 2015, pp 579–586 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

WaihiÆs Cornish Pumphouse is located on the edge of town in a dynamic and changeable area where history affects the future. As in any successful project, ingenuity and team work have been significant factors in the planning and implementation of the buildingÆs relocation.   Work around the Pumphouse site commenced circa 1900 with preparation to sink the No 5 shaft. Construction of the pumphouse and the steam driven C pump was completed by 1904 with hints of what was to come evident in 1905 as the No5 Shaft collar had sunk 350mm in four years. By 1907 surface cracking developed over the Milking Cow cave area and in 1913 200 mm was cut off the main pumping rod as the ground was sinking at a rate of 25 mm per year.   In 1913 ground around No 6 shaft had subsided 600 mm.It was also the end of an era as steam gave way to hydroelectricity and electric pumps replaced the C Pump. C Pump was maintained as a backup from 1913 to 1929 and then finally scrapped. 25 years of underground caving operations removed approximately 400 000 cubic metres of ore leaving a 7 ha collapse crater that eventually became known as the mine lake.   On the edge of town a tension zone over the Royal Lode began to develop 50 m diameter chimney collapses as large scale blocks relaxed into unfilled stopes in the old Martha underground mine. After the 1999 collapse part of the main street was closed and after the 2001 collapse Hazard Zones were declared, more streets closed and areas evacuated and retired from residential use.   By 1984 the Pumphouse has approximately one degree of tilt and in 2002 tilt on the Pumphouse accelerated briefly and then settled down. Tilt accelerated again late in 2004 and a scoping study was initiated to define protection options for the pumphouse. The Martha Mining Licence requires Newmont to 'Take whatever precautions are necessary to protect the old Cornish Pumphouse adjacent to No5 shaft' and viable solutions needed to found.   Any work on the Pumphouse comes standard with a wide range of stakeholders, governing agencies and legal framework to consider. Land Information New Zealand (LINZ) is owner and administrator of the pumphouse.

Jan 1, 2006

By Thirumalai K, Peluso R. G

The United States has more than 45 billion tons of economic coal reserves in seams above 10 feet thick and current underground production from thick seams represent less than three per cent of the total production. A tripling of underground production from thick seams is necessary within the next 10 years to meet U.S. coal production demands. An analysis of underground accident and production data is presented in the paper. A study of accident and injury distribution in different coal seam heights in the eastern and western part of the United States in seams ranging in thicknesses from 5 to 15 feet indicates that the seam thicknesses do not produce adverse impact on underground injury incidence. Accidents associated with roof falls and haulage account for about 70 per cent of underground mining injuries.

Jan 1, 1976

By J Pan

This case study assesses the application of Mine-to-Mill optimisation combined with Whittle Consulting’s Prober<sup>®</sup> economic optimisation for the purpose of economic value uplift in open cut base and precious metal operations. The study extends the application of these optimisation methods to incorporate the recent practice of Ultra High Intensity Blasting (UHIB) developed by Orica Mining Services. The case study deposit known as “Marvin” is a copper/gold porphyry resource that is commonly used in optimisation software training and industry case studies. It has many similarities to Newcrest’s Cadia Hill open pit mine in NSW. Prior desktop research and industrial trials employed static assessments of Mine-to-Mill effects. No prior work other than a Whittle Consulting client study, has sought to assess the impact of variable fragmentation on enterprise economic value. This study examines the use of variable blasting intensity as a driver of economic value maximisation over the mine’s life.CITATION: Howe, S and Pan, J, 2018. Application of enterprise optimisation considering ultra high intensity blasting, in Proceedings Complex Orebodies Conference 2018, pp 14–20 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018