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THE plant is one of the usual type of Mond plants, and contains no new features worthy of comment. A brief description of the process, however, with a few remarks on the working of the plant, may prove of interest.Producer gas is made by passing a mixture of air and steam through incandescent carbon contained in a furnace called a producer, which, in the Mond type, is a cylindrical casing of steel plate, lined with firebrick, and fitted at the lower end with sloping fire-bars'. Coal crushed to an even size (about 2-in. gauge) is elevated to bunkers over the producers, from which it is fed into a measuring hopper on each producer.The hopper is a cast-iron cylinder fitted with a swing cover at the top and a bell valve at the bottom, worked by a lever and balance weight. When a charge of coal is run from the bunker into the hopper, the cover is closed, and the bell valve is lowered, allowing the coal contents to drop into the producer. Thus no gas can escape from, or air be admitted to, the producer during the process of charging. The hopper discharges its coal through a steel pipe-shaped container called the bell, which projects about 9 in. through the roof of the producer. The function of the bell is to spread the coal evenly over the fire, and supply coal to any portion of the fire as it settles.

Jan 1, 1918

By Smith F. A, Both R. A

The application of biogeochemical methods in mineral exploration in the semi-arid to and environment of Western Australia was investiga- ted in an area near Norseman. The reliability of these methods was evaluated by comparing trace element characteristics of rock, soil and plants in the vicinity of the Pioneer BB pros- pect. The prospect is located in the south- western part of the Pioneer Dome, where granite gneiss core is surrounded by a 'greenstone' sequence of ultrabasic, basic and sedimentary rocks. Nickel-iron sulphide mineralization occurs discontinuously along one of the basic- ultrabasic contacts. Analyses of unweathered and partly weath- ered rock from diamond drill cores show the ultrabasic rock to be highly variable with re- spect to nickel, copper, cobalt, zinc and manga- nese. Samples of weathered bedrock and over- lying soil were analysed both for total trace element contents and for the trace elements associated with secondary iron and manganese oxides. Approximately 30 per cent of the total nickel content of the weathered basic rock is associated with secondary iron and manganese oxides, compared to approximately 15 per cent in the weathered ultrabasic rock. The soil is partly transported but has a residual component sufficient to provide a reli- able indication of the underlying rock chemistry, although the trace element content of the soil is less variable than that of the rock. Total

Jan 1, 1973

By M Berndt

Four siltite-argillite rock samples were characterised (particle size, chemistry, mineralogy) and subjected to laboratory dissolution testing for 36 to 298 weeks. In two samples sulfur (0.99, 1.69 wt per cent) occurred largely as pyrite, and in the other two samples sulfur (0.96, 1.93 wt per cent) occurred predominately as potassium jarosite. The observed rate of sulfate release from the pyritic samples was one to two orders of magnitude greater than that from samples containing potassium jarosite. Drainage pH values from the pyritic samples were one to two units lower and acidities were ten to 70 times higher than associated values from the potassium jarosite samples. Geochemical modelling supported the hypothesis that pH and concentrations of sulfate and potassium in drainage from the potassium jarosite samples were controlled by the limited solubility of potassium jarosite. This dissolution produced an iron-dominated mineral phase, but iron concentrations in the drainage were well below those predicted by ferrihydrite solubility.

Jan 1, 2003

By J Tickner, Y Van Haarlem, G Roach, D Abernethy, M Smith, J OÆDwyer

The development of novel technologies capable of real-time, high-accuracy, automated analysis of gold, other precious metals and mineralogy, both in ore samples and directly on process streams is reported.X-ray fluorescence (XRF) analysis is widely used for process stream monitoring of base metals. However, detection limits are generally a few parts-per-million (ppm) or larger, precluding the use of this method for monitoring precious metals. Complex interferences with other elements also limit accuracy. An XRF slurry analyser that uses advanced data-analysis techniques to resolve overlapping fluorescence lines, achieving detection limits in the parts-per-billion (ppb) range has been developed. This allows feed, concentrate and tailings streams in precious metal applications to be monitored in real-time. An extended trial of our technology in a platinum group element concentrator and laboratory tests on gold process slurries in the 0.1 - 2.0 ppm concentration range is discussed.Analysis of process stream mineralogy can provide useful information to supplement conventional elemental data. An on-stream X-ray diffraction analysis technique that provide real-time mineral and elemental measurement of process slurry streams has been developed. Both X-ray techniques can be combined into a single on-stream analyser to provide simultaneous elemental and mineralogical information. The successful trial of a combined XRDF (X-ray diffraction and fluorescence) slurry analyser is also reported.It is widely recognised that rapid, accurate analysis of grade is an essential prerequisite for optimising the efficiency of exploration, mining and processing of metals ores. The low grades of precious metals ores, such as gold and the platinum group elements, have led to fire assay becoming the predominant analysis technique. Significant drawbacks of fire assay include long turn-around times, limited absolute accuracy, high costs and requirement for skilled operating staff. For rapid measurement of gold samples, a technique that allows the gold content of large samples to be determined absolutely with high accuracy in less than two minutes using activation with high-energy X-rays has been developed. The method is non-destructive, has detection limits in the low ppb range, is capable of measuring slurries, ground or crushed solids with minimal preparation and can be made fully automatic. Initial results from laboratory trials are presented.CITATION:Roach, G, Abernethy, D, OÆDwyer, J, Smith, M, Tickner, J and Van Haarlem, Y, 2013. Advanced instrumentation for analysis of exploration, mining and process materials, in Proceedings World Gold 2013 , pp 277-282 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 26, 2013

By A Hall, D Kratochvil, P Littlejohn

Economic recovery of gold from complex gold ores, including poly-metallic deposits, is impacted by the presence of cyanide-soluble base metals. These base metals can create both a metallurgical challenge plus waste handling and disposal challenges. Base metals such as Cu and Zn compete for the cyanide reagent and often increase the total cyanide consumption to the point of making precious metals recovery uneconomic. In addition, the accumulation of base metals in cyanide solutions represent a challenge for cyanide detoxification and waste water treatment as these metals report to waste sludge. Such sludge requires safe handling and disposal, with possible long-term liabilities.Base metal interference can be removed with sulfidisation-acidification-recycling-thickening (SART) process technology. SART liberates the base metal from the cyanide complex and precipitates the metal as an insoluble sulfide product that can be recovered as a commercial grade concentrate. With the base metal precipitated, the cyanide can be regenerated as free cyanide and recycled to the gold extraction circuit.BioteQ completed laboratory testing for two projects, one employing cyanide leaching of copper-gold sulfide flotation concentrate and one employing a Merrill Crowe process, to determine the effectiveness of SART to remove and recover Cu and Zn in high-grade sulfide concentrates and to reduce the impact of cyanide-soluble metals on gold recovery and cyanide consumption. This paper will provide an overview of the testing methodology and results along with a review of the potential for SART to be applied to complex gold ores with poly-metallic deposits to improve project economics, operability and waste management.CITATION:Littlejohn, P, Kratochvil, D and Hall, A, 2013. Sulfidisation-acidification-recycling-thickening (SART) for complex gold ores, in Proceedings World Gold 2013 , pp 149-156 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 26, 2013

By C W. Lu, Y F. Chen, M J. Lian, W W. Guo

This paper proposes a set of new approaches for the optimisation of planning and designs in mines by means of evolutionary algorithms, which include the determination of ore grade, layout of development system, selection of mining methods and production scheduling in underground mines. The applications indicate that evolutionary algorithms are particularly suitable to the complex and complicated problems in mines.

Jan 1, 2003

By C Bonini, A Markham, P Whittle, B Pearson

"Mine-derived sedimentation in rivers can have significant impacts on the processes and features of the receiving environment and impact on communities reliant on this environment. However, identifying and quantifying the contribution of mine-derived sediment to the receiving environment can be complex. This is particularly the case in remote environments and where little/no baseline assessments have been undertaken. One approach that can be used involves sediment fingerprinting, whereby a unique tracer is identified within the mine-derived sediment to discriminate between mine- and non-mine derived sediment sources downstream. The technique typically involves sampling of sediment at upstream, control and impact sites and sites within the mine deposit. Laboratory analyses are run on all the samples to determine whether the chemical signature (eg presence/concentration of specific metals) differs between each group of samples. In complex environments where the mine-derived signature may be difficult to detect from a basic review of the data, or where sampling constraints may limit the number of samples for analyses, statistical methods can be used to help identify sediment groups. This paper provides a mine case study to show how such an assessment can be undertaken despite the logistical challenges faced while working in remote environments.CITATION:Pearson, B, Markham, A, Bonini, C and Whittle, P, 2013. Fingerprinting and signatures - tracing mine impacts in complex aquatic systems, in Proceedings Water in Mining 2013, pp 287-292 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 26, 2013

The success of any industry depends on the planned integration of the policies and resources of the key components of the Australian economic and political structure - government, industry management, education, research, and the human resources of the industry. The Australian Mineral Industry, like Australia itself, has grown and developed at a rate not foreseen by many of our founding fathers and early industry leaders. Hence, now, as we approach the 21st Century, we need to re-think our approach to the significant new problems that are beginning to face both government and the Mineral Industry. Government initiatives, government information and support services, industry re-structuring, and research and development support, need to be carefully re-evaluated, re-diredted,. and strengthened, so that government, the community, and the Mineral Industry produce and receive the optimum education and research strategies and services. The support of academics and researchers, the development of facilities, and the design of new Courses for the future successful and beneficial exploitation of minerals need particular consideration.

Jan 1, 1986

By J J. Cilliers, K Hadler

Air is fundamental to flotation; not only is it required to collect the valuable particles, but it also controls the froth stability and consequently the separation performance for a given feed. Froth stability can be described and quantified in numerous ways, which are subtly different. Air recovery is one such measure of froth stability which accounts for both the stability of the bubbles and the mobility of the froth. The benefit of using air recovery as a measure of froth stability is that it exhibits a peak as air flow rate is increased, and this corresponds to the air rate at which the optimal separation performance is obtained. As such, it provides a single target value for optimising air flowrate for a given set of feed conditions. Use of air recovery, however, has one potential drawback: accurate measurement of the inlet air flow rate to a flotation cell is required. This can be problematic for operations, particularly where calibration of air flow rate is carried out infrequently or where there is no air flow rate measurement, such as for many self-aerated flotation cells. To this end, we present an alternative method for determining the peak in air recovery (PAR) air rate.We introduce a simplified method for determining the PAR air rate using trends in froth velocity and overflowing froth height, both of which are readily measured using existing froth image analysis systems. We will show, using industrial data, the application of this simple technique to find the optimal air flowrate for flotation cells. We will also discuss other alternative techniques for air rate optimisation that have the potential to improve separation performance using existing technology.CITATION:Hadler, K and Cilliers, J J, 2018. How to find the optimum air rate for flotation cells, in Proceedings 14th AusIMM Mill Operators' Conference 2018, pp 377–384 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018

By M Grigorescu, S Crimp, J H. Hodgkinson, P Kokic, W Jin

Mines are typically located in remote, inhospitable locations and movement of materials between site, processor and port are often at risk from extreme weather events. Mining companies have recorded multiple supply chain, production and logistics delays caused by climatic events. Recent analyses of extreme temperature and rainfall events (90th and 99th percentile values) for 1960 to 1985 and 1986 highlighted regionalised increases in the frequency and intensity of extremes. The trajectory of this change is likely to be maintained (IPCC, 2014) in regions where increases have occurred historically, suggesting that some parts of the industry may be faced with management challenges beyond current experience (Hodgkinson et al, 2010; Loechel, Hodgkinson and Moffat, 2012). Reliance on historical data to plan for extremes (such as scheduling production downtime to reduce impact) will become increasingly ineffective as the data become less representative of future conditions. Importantly, mine site remediation and closure management need to consider the future climate to ensure rehabilitation is sustainable under changing conditions.Vulnerability assessments and risk-reducing adaptation will become more common as the industry reaches to secure both a mine’s longevity and the industry’s reputation as shareholders and clients become less tolerant of repeated or prolonged interruptions (Hodgkinson, Hobday and Pinkard, 2014). Climate-resilient new mines may be planned using site planning tools combined with knowledge of future climate scenarios. Scenario tools are valuable for developing a gated risk management approach to reducing climate-risk during a mine’s life, through to the rehabilitation process and for managing care and maintenance or closed mines.CITATION:Hodgkinson, J H, Crimp, S, Jin, W, Kokic, P and Grigorescu, M, 2016. Life-of-mine planning tools for a changing climate – intuitive, interrogative, iterative, in Proceedings Life-of-Mine 2016 Conference, pp 71–74 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By Sataev IS, Malinovskaja ND, Otrozdenova LA, Knodov NV, Maximov II, Kuznetzou OK

The technology of flotation recovery of silver from the residue of a zinc plant is described. The peculiarity of this technology is a preliminary pulp conditioning in sodium chloride solution in the presence of aluminum metal under high temperature. In this process the silver is converted to the metallic phase and then floated with the usual sulphydryl collectors. A variant using a combined technology is also described, in which before flotation is performed about 50 per cent of silver is leached. The total silver recovery with the combined technology comes up to 90 - 94 per cent.

Jan 1, 1993

By P Breuer, A Simons

The sulfidisation, acidification, recycle and thickening (SART) process is currently being used at NewcrestÆs Telfer Gold Mine to recover cyanide and copper from the cyanidation tails of the pyrite concentrate carbon-in-leach (CIL) process. While the process has been effective at attaining high recoveries of cyanide and copper, the Telfer SART plant has experienced higher than expected sulfide additions to achieve these recoveries. This paper details the results of surveys on the Telfer SART plant, which show that residence time appears to be causing the high sulfide consumptions. The paper also details the results of laboratory scale experiments which confirm the observed residence time impact during the acidified stage of SART.CITATION:Simons, A and Breuer, P, 2013. The impact of residence time on copper recovery in Telfer Gold MineÆs cyanide recycling process, in Proceedings World Gold 2013 , pp 189-196 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 26, 2013

The emergence of a new range of database communication standards and software has provided the impetus for the development of a new approach to exploration and mining data management. The acQuire software produced by acQuire Software Pty

Jan 1, 1998

The mining, metallurgical, and petroleum industries can be viewed as financial or as social institutions or both. The differences between these two conceptions of their businesses will influence their environmental and social actions. During the next 10-20 years western industry will be subject to a drop in the growth of a more highly educated labour force and to the emergence of holistic economics, new national goals, and a new ecological perspective. The profitability of the mining industry may therefore be influenced by the human side of its business to a greater degree. The increas- ing human, social, and environmental responsibilities can be discharged by improving the miner's equip- ment; by learning to look at situations through the eyes of all those involved; by developing common `languages' which governments and the public can understand; and by mediating where feasible on the international scene.

Jan 1, 1978

An automatic control system of a longwall roof support is dis-cussed. Hydraulic automatic control systems for longwall roof support have not met all requirements for such systems. Utilization of standard hydraulic elements to form a system that would-comply with all demands leads to a very complicated structure with a large number of hydraulic hoses within and between adjacent supports. So, only simplified systems have been made. This paper describes the multifunctional valve that per-mits realization of any desired logic functions, while maintaining a com-pact form, and analyses its application as a fully hydraulic automatic control system of a roof support.

Jan 1, 1985

By J Hudson

Autogenous (AG) and Semi Autogenous (SAG) grinding mills are the conventional selection for large-scale grinding circuits. It is accepted that these forms of comminution are not the most energy efficient available. This efficiency combined with escalating energy prices, steel prices and the requirement to process larger, lower grade deposits has necessitated that better comminution techniques are found to challenge the dominant position of AG/SAG mills in the grinding circuit. Recent advances in high pressure grinding rolls (HPGR), particularly in terms of roll surface protection have meant that, depending on the application, an economic alternative is available to the large diameter AG/SAG mills. Mining companies now recognise the potential benefits of HPGR and so they need proper assessment in the design of new or upgrade of existing grinding processes. Of course, the answer to the question AG/SAG or HPGR is not straightforward and the impact of the grinding process on the whole metallurgical process needs to be evaluated. Clearly this is a complex decision to make and requires substantial metallurgical knowledge, test work, and objective analysis. The perceived downstream processing benefits will differ between different plants depending on the ore type and processing conditions. The optimal design of the comminution circuit requires that a robust methodology is followed to objectively characterise the ore, size the equipment and determine the downstream processing benefits. The paper gives a brief comparison of the capital and operating costs for both grinding systems, and then outlines the appropriate test work that is required to make an informed decision.

Jan 1, 2006

This study introduces a new probabilistic approach to seismic stability analysis of embankments and slopes. The approach is based on Sarma's solution, which is modified through presentation of the seismic force by its horizontal and vertical components; i.e. the force may have an arbitrary inclination. The probabilistic modelling includes Monte Carlo simulation of the shear strength parameters of the soil mass, which are assumed to have a normal distribution. The probability of failure is determined based on the seismic co-efficient, which is treated as a random quantity. The probabilistic approach is illustrated through a solution of a numerical example from an opencast coal Mine.

Jan 1, 1992

By Y Li, B Shen, S Zhang

Jointed rock mass is often encountered in rock engineering and its stability has always been a major concern in underground engineering. To analyze the stress characteristics and their variations in jointed rocks, in this study, a new concept of sub-instability stage before rock failure is defined, and a new experimental method is used to investigate interaction between defects and intact rock of the jointed rock mass during the subinstability stage., Firstly, external characteristics of stress and failure mode of the whole jointed rock are investigated systematically by conducting uniaxial compression tests on red sandstone samples with a set of preexisting open flaws of different sizes, and the interactive damage of intact parts and defects in the subinstability stage was further studied. Secondly, rock-like material samples made of bonded plaster blocks were tested and internal data from stress sensor between the strong and weak segments were collected. The transforming processes from independent activity of the individual segment to overall interactive movement of jointed rock before the unstable failure were analysed. The test results indicated that the subinstability stage marked the beginning of interactive failure between the intact rock and defects. In the early subinstability stage, the relatively intact parts bore most of the load in a jointed rock mass, and the defects were damaged firstly which caused high strain around it. The areas of high strain increase rapidly, extending and migrating, causing damage to the intact parts. In the later sub-instability stage, the interaction effect reached its maximum, and a large number of cracks appeared in the intact rock and they propagated and coalesced. Intact parts experienced rapid failure and then the jointed rock failed. The experimental method used in this paper to identify the sub-instability stage could be used to identify failure precursors of jointed rock masses and to develop technology for disaster prevention in rock engineering. CITATION:Zhang, S, Shen, B and Li, Y, 2018. Experimental studies on interactive failure characteristics of jointed rock, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), pp 453–461 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

By R Berry, J Lett, C L. Harraden

"In the past decade, increased processing capacity combined with precision robotics in high resolution spectrometers has resulted in a new generation of high-speed hyperspectral core logging systems. The application of these multisensor automated platforms provides a key advancement in the characterisation of metal resources. The development of this technology has allowed for comprehensive, drill core-based, mine-scale rock mass characterisation studies. Here we propose a new method for the extraction of parameters that seek to more accurately quantify ground conditions, including quantified rock mass rating (RMR) and the Rock Tunnelling Quality (Q) Index. Data inputs include rock quality designation (RQD), number of joint sets, joint roughness, joint alteration and joint spacing. Geologists and geotechnical engineers have historically collected these inputs by manually logging drill core. With automated core scanning technologies, these parameters can be estimated from the acquired image data and used to objectively calculate RMR and Q-index values for oriented core.Corescan is an automated hyperspectral core scanner that uses a 3D laser profiling system to measure the height of the surface of drill core. This technology allows for rapid core analysis to produce detailed fracture and rock condition data. Through an integrated geometallurgical approach, the proposed methodology will test the accuracy of joint measurement using the height profile Corescan data from oriented drill core. This will be combined with joint roughness and alteration mineralogy measured from the hyperspectral images to calculate the RMR and the Q-index continuously downhole. The values obtained can then be compared to the traditional, manual geotechnical log data. If the precision is sufficient, these techniques can then be applied site-wide to automate the collection and modelling of key ground condition classification indices across an entire deposit. Compared to the laborious manual geotechnical logging procedures that currently form the industry standard, utilisation of core laser profile data and high resolution red-green-blue (RGB) images provide an opportunity to collect large volumes of consistent geotechnical data, which can increase the efficiency and accuracy of deposit scale geotechnical models.CITATION:Harraden, C L, Berry, R and Lett, J, 2016. Proposed Methodology for Utilising Automated Core Logging Technology to Extract Geotechnical Index Parameters, in Proceedings The Third AusIMM International Geometallurgy Conference (GeoMet) 2016, pp 119–124 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jun 15, 2016

By Lean P. J

The present The Zinc ODrporation, Limited and New Broken Hill Consolidated Limited (ZC/NBHC) tailing dam (Site C) is expected to reach its terminal capacity late in 1985. Planning and design of new facilities for disposal of tailing after 1985 which includes new tailing dams (Site D) commenced during 1980. This paper briefly describes planning guidelines and specifications, location considerations, environmental aspects, operating strategy, engineering specifications, envirormental aspects and scheduling of works.

Jan 1, 1983