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The Pacific Rim and its environment involves a vast array of natural phenomena, and a vast array of situations which show the impact of man. Almost half the world's population of over five billion live in nations" which border the Pacific, but the concentration is focussed in the North. Great experiments are occurring in this region, the industrialization and energy development in- Japan and China, the growth of Indonesia, (now 168 million - soon 368 million; Brown and Jacobson, 1986), the enormous developments of agriculture and the metals resource base in Australia and China. At the same time, the Pacific Rim does not project images of hopelessness, the mood is upbeat. Over the past decade, incomes have increased substantially in most of the major countries of Pacific Rim (e.g. over the period 1980-86, + 58% in China, + 21% in Japan, + 34% in South Korea; Brown and Jacobson, 1986). In September, 1986, at the general assembly of the International Council of Scientific Unions (ICSU) in Bern, Switzerland, representatives of over 50 nations approved a new initiative, "The International Geosphere Biosphere Programme: A Study of Global Change". The focus of this new program is "To describe and understand the interactive physical , chemical , and biological processes that regulate the total Earth system, the unique environment that it provides for life, the changes that are occurring in this system, and the manner in which they are influenced by man. The IGBP will be a tightly-defined programme of research, directed at providing fundamental knowledge that will serve as a basis for assessing likely future changes on the Earth in the next 100 years" (ICSU, 1986). For the earth scientist, and all resource scientists, there is an emerging agenda; new priorities are appearing, new questions are being asked. The recent report of the World Resources Institute (1986) focusses on this emerging agenda. Topics which are at centre stage in this report include the following: The environment and human health Tropical deforestation The atmosphere as a shared resource and climates Soil-degradation Rural-urban migrations Food and agriculture The diversity of species-ecosystems Freshwater as a finite resource Coastal areas and resources

Jan 1, 1987

By D A. Collins

The floatability methodology developed by the AMIRA P9 project through research contributions by the Julius Kruttschnitt Minerals Research Centre (JKMRC, Brisbane, Australia), University of Cape Town (UCT, Cape Town, South Africa) and McGill University (Montreal, Canada) has been successfully commercialised through JKTech. The methodology involves detailed flotation plant campaigns which require large quantities of data to fit models that can be used in JKSimFloat (a steady state simulator for the flotation process). The methodology to date, although widely accepted as the best flotation optimisation technology available, is limited to existing circuit optimisation and requires full plant or pilot plant data to calibrate new models. The floatability of new ore types cannot be characterised using this method unless a pilot campaign is undertaken. After reviewing a large database of existing industrial floatability data, a new methodology is proposed that involves a laboratory based flotation test procedure and review of the floatability database to characterise the floatability of new ores. The full methodology is labelled the floatability index test procedure (JKFIT). This paper outlines the JKFIT procedure and the results of applying this methodology to pilot plant data from a copper ore. JKFIT was applied to two different feed sizes (namely a P80 of 180 microns and 212 microns) of this copper ore. The results of applying JKFIT to this case showed that the metallurgical response (in terms of grade and recovery) from the full pilot plant survey data could be predicted well. Further validation of this methodology was conducted on a separate copper ore. The results from this validation also showed that the JKFIT test was able to be used to predict the full plant performance. The JKFIT test has the potential to become the 'drop weight' test of flotation which will improve the confidence in plant design flow sheet layouts, allow full orebody characterisation and prediction of key grades and recoveries before the ore enters the plant, and will provide an improved methodology for chemistry impact analysis on different ores.

Jan 1, 2008

By A Sadri, S Smith

In the metal and mineral industry, different empirical techniques are used to estimate the remaining thickness of the lining within an operating furnace. The disadvantage and costly factor when using these methods is that production needs to be halted. Hatch has developed an accurate and reliable technique based on stress wave propagation principles to determine the condition of the remaining lining whilst the furnace remains online and operational.The technique involves test data collected and compiled to generate 3D imagery used to assist operators and maintenance planning personnel with valuable information showing areas of metal penetration in the lining, remaining lining thickness, exact location of voids, cracks, poor contacts and deterioration due to chemical attack. In this paper, the principals of the AU-E technique will be explained both theoretically and practically. In addition, the use of ultrasound technology for determining the condition of copper cooling elements will be briefly addressed.

Jan 1, 2006

By G Guy, J Summerville

Over the past five years in coalmine slope evaluation the application of 3D modelling has increased significantly as software has become more user friendly but also areas requiring evaluation have become increasingly complex. Often simplistic 2D Limit Equilibrium modelling and analysis has been poorly used to solve slope stability issues by back analysis and subsequent forward predictive analysis. A plane strain condition with slope movement perpendicular to the slope strike is assumed where in reality the problem is more complex. This often leads to a misinterpretation of the failure mechanism because the failure mechanism being modelled in 2D does not generally represent the actual failure mechanism observed in the pit, with 2D modelling often oversimplifying a slope. This paper presents a case study where the initial slope assessment and remedial design evaluation was undertaken as a 2D Limit Equilibrium model which led to an overly conservative and costly remedial solution being implemented. Subsequent modelling of the slope using both 3D Limit Equilibrium and Finite Element methods were able to provide a better understanding of the structural complexities associated and correlate well with slope monitoring data to create a more realistic outcome.

Nov 29, 2022

By X Xia2, X Wang, G Liang, T Song, F Ma

Inertia cone crushers have found applications mostly in steel slag crushing operations in China. Compared with conventional eccentric cone crushers, the crusher has an obvious advantage in reducing product size. In addition, they are mostly used in two-stage open circuit crushing flow sheet, which simplifies the crushing process. However, inertia cone crushers are not widely used in the mineral processing industry due to their low crushing capacity. In this paper, the throughput performance of the inertia cone crusher was investigated in a laboratory-scale inertia cone crusher and relationships between operational parameters were identified. Iron ore was crushed using orthogonal experimental method under different machine parameters and operational conditions. The crusher throughput and product size distributions were determined. The effects of parameters such as eccentric speed, discharge gap, eccentric mass and eccentric distance on product mass flow and product size were investigated. The results of this study can help reduce the feed size of the mill in order to reduce total energy consumption of comminution.

Aug 24, 2022

By G Collecutt, D Proud, D Humphreys

"The hazards associated with dust explosions are well known, and coal dust explosions present a significant hazard in the underground coal mining industry worldwide. In earlier work, we presented computational fluid dynamics (CFD) simulations and test results for coal dust explosions within a 2.5 m diameter circular gallery, along with CFD simulations and test results for the suppression of these explosions with finely atomised water sprays. In this paper, we present refinements to the CFD modelling that yield a significantly improved calibration with the test results, and proceed to investigate by CFD the requirements for suppression of a coal dust explosion in a typical underground roadway. This work was carried out under an ACARP project and we gratefully acknowledge their assistance. CITATION: Proud, D, Collecutt, G and Humphreys, D, 2015. Computational fluid dynamics modelling of coal dust explosions and suppression systems, in Proceedings The Australian Mine Ventilation Conference, pp 309–314 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Aug 31, 2015

By Bluck R. G

The Murray Basin is known to contain major deposits of heavy mineral sands and intensive exploration for new deposits is being conducted in Victoria, South Australia and New South Wales. The western Basin was well served in the Pliocene and Early Pleistocene by a variety of appropriate sediment sources, and potential coastal traps. Immature, fluvially-sourced sediments forming the Pliocene coastal complex of the Marmon-Jabuk Range in South Australia are part of a marginal marine assemblage containing a suite of economically important heavy minerals that include ihnenite, zircon, rutile and tourmaline. From a consideration of Pliocene palaeogeography and coastal dynamics, specific targets where concentrating processes are likely to have operated are identified in the South Australian portion of the Murray Basin. Such palaeo-environments include the down-drift, littoral zone of discrete foredunes or coastal barriers, the source area for transgressive dune complexes, tombolo facies, and intertidal shoals and sandbanks. Similar coastal processes are recognised for a preserved Early Pleistocene barrier complex.

Jan 1, 1990

By I H. Jung, W O. Choe

Gallium (Ga)-containing compounds such as Gallium Arsenide (GaAs) and Gallium Nitride (GaN) are widely used in electronic devices due to their superior electro-optical properties and their usages increase rapidly. For the sustainable supply of Ga to electronic industry, therefore, the recycling of Gallium becomes essential. Pyrometallurgical Ga recycling process involves the complex chemical reactions between slag, matte, liquid metal, gas, refractories, etc. Therefore, the accurate thermodynamic information and phase diagram data for the oxide system containing Ga2O3 is important. In the present study, new phase diagram experiments for binary SiO2-Ga2O3 and ternary CaO-SiO2-Ga2O3 system are carried out using Differential Thermal Analysis (DTA) and quenching experiments followed by Electron Probe Micro-Analyser (EPMA) and X-Ray Diffraction (XRD) phase analysis. Based on new phase diagram data and available literature data, the thermodynamic modelling of the entire CaO-SiO2-Ga2O3 system is performed for the first time.

Jun 19, 2024

By Peck WH

For many years it was realised that the methods used for unloading concentrates at Port Pirie were inefficient and labour intensive, therefore, when a decision was reached to standardise the east-west rail link from Sydney to Perth, the opportunity was taken to consider entirely new schemes for the handling of concentrates at Broken Hill and Port Pirie. After considerable testing and investigation, it was decided to install a completely new concentrates handling plant incorporating a tippler at Port Pirieòto replace the previous long established methods of unloading and dis- tributing concentrates to the operating plant.and the shipping berths. To achieve this, wagons of concentrates from the various mines are marshalled in a set order at Broken Hill and conveyed to Port Pirie in 56-wagon trains. On arrival at Port Pirie, the wagons are checked and moved to a position where they come under the control of the automatic wagon marshalling equipment.

Jan 1, 1975

Using a new type of laser surveying instrument named Particle Dynamics Analyser (PDA), the distributions of the radial and axial components of the mean velocity, the size and the concentration of solid particles at selected positions within a transparent hydrocyclone were directly measured out for the first time, from which profiles of the flow field of solid particles were obtained. And some new points were put forward such as the locus of zero vertical velocity (LZVV) of solid particles was not the same as that of liquid, and some particles in inner helical flow could also be separated. The results are of great significance to farther ascertain the separation principle of hydrocyclones and improve the separation efficiency.

Jan 1, 1993

By Lin Bin, Minggao Qian, Zhiyi Yang, Fullan He

There are no efficient methods and instruments available in China at present for diagnosing the leakage problem for a hydraulic support system in underground coal mines. A new method has been developed to solve the problem. It is proposed that

Jan 1, 1998

By S Mitra, T Singh, D O’Dea, T Honeyands

Permeability and air flow rate in the bed during iron ore sintering is crucial to controlling the sinter quality and productivity of a sinter plant due to its influence on the flame front speed. In the present work, the permeability of the bed during sintering was analysed by means of measured pressure drop and temperature at multiple points in the bed during sintering. Three different zones were categorised, ie humidified (green) bed, region of maximum resistance (high temperature zone) based on temperature, and sintered bed. Previous work has shown that the maximum pressure drop during sintering was due to several concurrent physico-chemical processes including dehumidification, calcination of fluxes, dehydroxylation of goethite, combustion of coke and melting of granules (>1200°C). To quantify the effect of the different process, sintering experiments were conducted in a milli-pot (diameter 53 mm, height 400 mm) with pressure and temperature measured at same location in bed. The milli-pot was fitted with four equidistant (80 mm apart) taps. Overall, five sections in the milli-pot were analysed for pressure drop at different times during sintering. It was found that in region of maximum resistance, coke combustion and flux calcination were highest contributors with ~35 per cent of the pressure drop when compared to other processes like de-humidification and goethite dehydroxylation which contributed to ~20 per cent and 25 per cent each respectively. The pressure drop contribution of the coke combustion region increased with increasing coke addition rate.

Nov 8, 2021

By D David

The development of Western Australian magnetite deposits has lead to the design of some of the largest grinding mills and plants in the world. One of the projects demonstrates the efficiency gains possible by developing a simple yet thorough test program for circuit design. By drawing on the experience of current magnetite operations in Australia and the Mesabi and Marquette iron ranges in the United States, a basic flowsheet was developed. Through comprehensive testwork with AG, ball and stirred milling the flowsheet was optimized to take full advantage of each grinding mill’s strengths to reach the required final grind size. Laboratory work was verified in the pilot plant to optimize the energy efficiency of each grinding step while ensuring adequate liberation at each step for sufficient gangue rejection. By using three stages of grinding, the ball mill can best be employed in ensuring all top size gangue material is liberated and removed in the second magnetic separation step. The inclusion of the IsaMill, with its inherent steep product size distribution, as the tertiary grinding stage ensured that maximum grade was achieved and simplified the downstream process while giving further improvements in total grinding capital and operating costs. In this way the combination of the two technologies downstream from the AG mill is far more efficient than either would be on its own by reducing the total installed power by 1/3 and annual grinding media cost by 2/3.

Aug 8, 2011

By T B. T Nguyen, L Matthews, D O’Dea, T Honeyands, T Harvey

Productivity and fuel consumption of the blast furnace is driven by the quality of the iron ore sinter, which in turn is related to the sinter mineralogy. The sintering conditions including temperature and gas composition have a significant influence on the formation of melt and finally the mineralogy of the sinter. In this work, analogue sinter tablets were produced from iron ore fines in a laboratory furnace with tightly controlled temperature profile and oxygen partial pressure in the gas. The mineralogy of the sinters was analysed using reflected light microscopy. The results showed that increasing thermal enclosed area (area enclosed by heating and cooling curve above a reference temperature) reduces primary hematite and platy silico-ferrite of calcium and aluminium (SFCA) contents. This is attributed to increasing melt formation, leading to greater assimilation of the iron ore particles. Lower magnetite was found for tablets with greater median pore size, which is thought to be due to greater oxidation of magnetite to hematite during cooling in air. It was also found that higher alumina content was found to result in more SFCA formation under the same heating/cooling conditions, whereas tablets with higher goethite had higher assimilation and produced more secondary hematite on cooling. Finally, it is necessary to relate the enclosed area to the temperature at which the melt formation becomes significant which strongly depends on chemical composition of the ore studied.

Nov 8, 2021

This paper presents a rationale for selecting appropriate support elements which combine to form a support system to maintain stability in mines subjected to both strainburst and the shaking that occurs from fault slip. The overall approach was developed during the 'case for safety' study undertaken to allow the then Beaconsfield Gold mine (now Tasmania mine) to resume development and production after the 25 April 2006 ground-fall and fatality that received worldwide publicity. Issues of the sometimes competing requirements of support element performance during dynamic loading are discussed and the need for support flexibility is contrasted with the usual high support element stiffness required when these are used to reinforce rock masses. An example is presented to show the steps and technical details required to design each component of a support system to counter the de-stabilising effects of seismicity.

Nov 25, 2010

By J-P Franzidis

Mill operators have traditionally been forced to rely on grade-recovery curves and overall flotation rate constants when analysing proposed improvements to plants. This has led to loss in money and time when a proposed change that showed potential in laboratory scale tests failed to show improvement in the plant. Frequently, this is a result of the operators being unable to gain insight into how and why the proposed change affected the flotation performance. This is due to the classical models not including any description of the subprocesses of flotation and their individual contribution to the overall flotation performance. A new flotation model has been developed as part of the AMIRA P9 project that separates the flotation process into subprocesses and includes the contribution of both the pulp phase and froth phase to the overall flotation recovery. It is not possible to determine the individual components of this new model on traditional pilot plants as they lack the required flexibility and scale. Therefore a new pilot plant has been developed known as the Floatability Characterisation Test Rig (FCTR) that has the flexibility and features required for the determination of the flotation subprocesses. The flexibility and features of the FCTR also make it an ideal tool for investigations into many different aspects of flotation research. These include the effect of reagents, grinding, and power on the flotation performance. This paper will describe the methodology for using the FCTR in these fields of research and highlights the advantages of using the FCTR over traditional methods.

Jan 1, 2000

By M Mee, R L. Gwyther

Accurate measurement of rock mass response during the mining of massive underground orebodies is essential, as mines become larger and deeper. These measurements enable: provision of quantitative data for optimal pit slope design and engineering; monitoring of the stability of deep pit slopes, the long-term integrity of shafts and large-scale underground infrastructure, and long-term measurements of deformation or rock mass creep following the mining process for environmental management. Strainmeters traditionally used for deformation measurement have neither the long-term stability nor the high sensitivity to perform measurements in these applications. This paper describes a new precision borehole strain monitoring system (GTS) currently deployed by CSIRO Exploration and Mining, which has the potential to solve these new issues in rock mass deformation monitoring. This technology was originally developed for use in hard rock mines (Gladwin, 1977) and refined considerably for earthquake research (Gladwin et al, 1994; Gwyther et al, 1992). A case study of the use of the GTS in monitoring longwall coal mining over the period 1993 - 1998 is presented.

Jan 1, 2000

By W Y. Kim, Y B. Kang, Y J. Park

The phase equilibria in the Al2O3–TiOx system were investigated in wide ranges of temperature and oxygen partial pressure: 1300~1600°C and 10-16.6~10-8 atm, respectively. The equilibrium phases and their compositions were identified using X-ray diffraction (XRD) and electron probe microanalysis (EPMA), respectively. Most noticeably, a wide range of pseudobrookite solid solution was found in equilibrium with almost pure alumina. At each temperature, the cationic ratio expressed as RTi = nTi/(nAl + nTi)) of the pseudobrookite solid solution showed a noteworthy dependency on the oxygen partial pressure. This resulted in the formation of a broad range of pseudobrookite solid solutions, ranging from Al2TiO5 (RTi = 1/3) to Ti3O5 (RTi = 1.0). Complete miscibility within the pseudobrookite solid solution was observed at 1600°C, with only a minor miscibility gap becoming evident below 1500°C. Based on the results obtained in the present study, the behaviours of Al2TiO5 pseudobrookite have implications in two key domains: (1) understanding changes in the physical properties of the materials, and (2) elucidating the evolution of Al–Ti complex oxide inclusions in liquid steel which can deteriorate the steel cleanliness.

Aug 21, 2024

Samples weighing 0·5 g are fused with potassium hydrogen sulphate, leached with 4 ml. of 4 M nitric acid and diluted to 10 ml. with water. An aliquot of the clear solution is treated with EDTA, adjusted with ammonia to give a pH value between 5 and 6 treated with cyanide, ammonia, and sodium diethyldithiocarbamate then bismuth diethyldithiocarbamate is extracted with chloroform and the yellow colour is compared visually with a standard series. Alternatively, the bismuth complex may be filtered on a "Millipore" filter and subjected to x-ray fluorescence spectrometry.

Jan 1, 1971

The Electricity Commission of New South Wales is the largest single user of coal in the State, burning some 8.5 million tonnes during 1972-73. This coal is converted in power stations into electrical energy which is then distributed throughout the State and supplies the electricity requirements of 99% of users in New South Wales. Barring any major change in energy consumption growth, or change in the current mode of power generation, the consumption of coal by the Commission is estimated to have a doubling period of from 10 to 14 years. Coal is used to generate up to 87% of the electrical energy sold, the balance being obtained from hydro gen- eration, mainly in the Snowy Mountains, and, to a much smaller extent, from diesel generation at Broken Hill. A very large proportion of this coal is consumed in pulverised fuel boilers in the Commission's power stations, located mainly on the various coalfields of New South Wales. Coal supplies are drawn from a large number of mines, some owned or controlled by the Commission, others being owned by public companies. The coals used, originate from at least ten different seams located in the northern, western and southern coalfields of New South Wales, and therefore have a wide variety of properties and characteristics. To ensure an adequate fuel supply well into the future, the Commission is continuously engaged in coal prospecting in various areas. Bore data is used in assessing coal reserves and is also the basis of economic studies for their possible future exploitation. The numerous coal cores obtained during drilling operations are carefully tested and analysed in order to assess their suitability for power generation purposes, and to provide data for the design and operation of boiler plant using these coals. In existing power stations coal deliveries are systematically sampled and tested for quality control, for pay- ment of purchases based upon certain quality parameters and to check for any possible plant operating or main- tenance problems that might arise from the use of the particular coals. Almost all the properties of coal that may be necessary in the Commission's work are obtained using standard testing procedures carried out by the Commission's chemists, in laboratories located at the various power stations or at its Central Laboratories in Pyrmont. Where specialised analysis or testing is required, this is ordinarily undertaken on a commercial basis by outside bodies, expert in the particular field. The significance of the various properties of the coal for use in p.f. boilers is outlined and related to their proper application to boiler plant design and to plant operation.

Jan 1, 1975