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By Masszi D

INTRODUCTION The association of methane with coal has been known almost since coal was first mined and in general it has been considered the curse of underground coal mining. Historically, most of the effort to handle this methane has been directed at diluting it to a safe level and preventing an explosive mixture of methane and oxygen from forming in any part of the mine. This is generally achieved by in-mine activites. This approach has two principal drawbacks, the severity of which are dependent on local conditions. The first is that the activity associated with the handling of the methane is undertaken in the mine and there- fore competes with the mining activity for the limited space available. The second drawback is that the whole methane handling activity is generally a cost to the coal because methane is so diluted that it cannot be used. With the value of energy increasing thi; second drawback is gaining importance so th.u several mines in Europe and North America ;it,, now installing systems to recover the methane in a useful form. Two approaches are

Jan 1, 1982

By Berglin IK

Since 1962, ferro alloy production in Australia has been concentrated at Bell Bay, Tasmania with a major expansion occurring in 1976. This concentration was based originally on the perceived requirements of the expanding Australian steel industry, but recent stagnation within this industry has seen Temco become progressively more export oriented.In 1984, approval was given for a $47 million uprating of facilities which will allow for the introduction of the latest technology to ensure high quality, low cost production in a highly competitive export market.

Jan 1, 1985

By D Johansson, A Nordqvist, D Mihaylov, N Petropoulos, M Wimmer

The flowability of the caved rock masses in the sublevel caving (SLC) mining method is of great importance. During the blasting process of a SLC-ring, the caved rock mass in front of the ring is compacted. As a result of this compaction, the mechanical properties of the fractured rock masses change, for example void ratio, angle of internal friction and structure of the compacted material. The changed mechanical properties of caved rock mass and recent blasted material can influence the mobility of the material, which could result in blockage of the flow path of the material. The identification of the involved mechanisms in this process can be done after a series of tests in different scales. However, there is no available equipment for dynamic measurements during blasting, ie velocity and displacement of the burden and in the caved masses. This study focuses on the development and laboratory evaluation of a measuring system that can be installed in a borehole. The first trial was carried out in a pillar, where two blastholes had been drilled (9.5 m) parallel with the drift and two measuring holes (16.5 m) were perpendicular to the drift. Two measuring systems were installed in the measuring holes. Some preliminary tests were carried out to find suitable initiation procedures for the emulsion explosive. Applicability and robustness of the developed measuring system were also evaluated. In addition to these tests, an expandable cement mixture was developed to firmly anchor the measuring systems in the boreholes. The measuring system consists of an anchor, armoured cable in a pulling tube and a protective case. The anchor is equipped with uniaxial and triaxial accelerometers. A potentiometric measuring system for displacement up to 2 m is installed at the end of the pulling tube and connected to an extendable spiral cable. All sensors are connected to a data acquisition system (DAS). Both measuring systems have their own DAS to acquire data in case of failure of one of the systems. The measuring system was tested in laboratory conditions with impact velocity up to 10 m/s. It was proven to be functional and gave reliable results.CITATION:Petropoulos, N, Mihaylov, D, Johansson, D, Wimmer, M and Nordqvist, A, 2015. Design of equipment for dynamic burden measurements, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 493–500 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By D Blair, L Fergusson, G Barros

"The purpose of this paper is to present the findings of a waste rock remediation program conducted at a gold mine in New South Wales (NSW) over a six-year period. The treatment of waste rock dumps included the longitudinal results of one-off applications using: ViroMine Technology, including the application of a chemical reagent called Terra B, which is a benign, clay-like substance derived from processed bauxite and other sources lime and biosolids (added for nutrient value) clay capping and topsoil compared treatment outcomes from these three approaches to a control.Parameters measured in the program included leachate pH, total actual acidity (TAA) and chromium reducible sulfur (CRS), Al, Cd, Cu, Fe, Mn, Ni, Pb, Zn, and tree height and vegetative cover density with data collected at regular intervals over a six-year monitoring period. Findings over the life of the study indicated, for example, that leachate pH in the control area was 4.5 in year 1 falling to 4.0 by year 6; pH in the lime and capping treated waste rock was initially raised to about 5.5 after treatment but fell to 5.0 within 24 months and remained a low 4.7 by year 6; pH in the Terra B waste rock was 6.8 in year 1 immediately after treatment, and actually increased to 7.3 by year 6 with no further treatment. This finding is of relevance because it effectively profiles the acidity curves of waste rock control, lime, and capping applications, and shows that they decline over time, despite an initial æpH shockÆ to the solids as measured by TAA and CRS in the case of lime. Similar treatment curves were observed for heavy metal leachates. Tree height and vegetative cover density indicated that with increasing acidity in the waste rock dump, the lime and capping options did not allow healthy revegetation, but in the Terra B treated areas tree growth and density were comparable to background, undisturbed forest levels.is needed with respect to tailings management, based on a novel integrated research framework.CITATION:Fergusson, L, Blair, D and Barros, G, 2012. Sustainable waste rock remediation and revegetation - A real-world longitudinal study comparing ViroMine technology to standard applications and doing nothing, in Proceedings Life-of-Mine 2012 , pp 249-258 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jul 10, 2012

By S A. Johnson, J Cassidy, J L. Mauk

Geophysical anomalies at Puhipuhi reflect both diverse lithologies and different degrees of hydrothermal alteration. Most significant is a strong negative gravity anomaly (up to 50 g.u.), encompassing but extending beyond areas of known alteration, which is modelled as a deep zone (up to 3 km) of reduced density in the host greywacke basement. This zone, interpreted as being due to alteration (at least in part), closely correlates with the extent of overlying basalt flows. The gravity data indicate that the most intense alteration occurs below the basalts and correlates with the location of previously inferred hydrothermal upflow zones. These observations suggest that the basalt may have acted as a cap rock to a mineralising geothermal system. Aeromagnetic data identify highly variable but typically low magnetisations in the basalts which suggests that alteration may have been contemporaneous with volcanism. These geophysical data at Puhipuhi confirm the locations of centres of known alteration and suggest potential exploration targets below the basalt cap where there is no surface manifestation of alteration. Further implications of these results are discussed in Locke et al. (1999).

Jan 1, 1999

By B BussiFre, J Molson, M Aubertin, G W. Wils

Waste rock piles containing reactive sulfide minerals can serve as long-term sources of acid mine drainage (AMD). Within these piles, many physical, geochemical and biological processes can contribute to the production of AMD. The flow of water, for example, depends on internal pile structure, which depends on the dumping methods used to construct the pile. In this paper, the internal structure and grain size distribution of typical waste rock piles are first reviewed with respect to their effect on internal water flow. A numerical model is then applied to simulate unsaturated flow within a waste pile assuming two primary waste materials, different atmospheric conditions and several geometric configurations. The simulations suggest that water movement can be controlled by introducing fine-grained material layers within the coarser host material. However, these layers should not be horizontal because they can lead to localised high-saturation regions as well as preferential flow favouring the production of AMD. A shallow slope towards the pile boundary may be introduced to force drainage to the outside while maintaining low saturation within the interior, thus reducing the production of AMD.

Jan 1, 2003

By Ryan CG, Cousens DR, Griffin WL

The proton microprobe is developing into a vital tool in the geosciences, through its high sensitivity for in-situ detection of trace elements in the ppm regime. This paper will describe the instrument at the CSIRO Heavy Ion Analytical Facility at North Ryde, including features crucial to its successful application in the geoscience. Examples of applications in the basic geoscience and mineral industry related research are described briefly. Conditions required for widescale applications in the minerals industry are Discussed.

Jan 1, 1989

By P J. Bangerter, G D. Corder

With the societal desire and drive towards low carbon energy sources, there is a growing awareness of the important role that minerals and metals will play with renewable energy technologies. Copper is an essential metal for technologies that generate energy from renewable sources, in particular for wind and solar photovoltaic energy systems. A recent report (Arrobas et al., 2017) estimated that the median increase in copper demand through to 2050 for wind technologies and for solar photovoltaics would need to be 250% and 300% respectively to meet the goal of a 2°C global temperature increase scenario compared with a 6°C global increase, which is largely an extension of current trends (IEA, 2018). The aim of this extended abstract is to demonstrate with the necessary increase in copper production for renewable energy technologies that sound sustainability performance across the global copper value chain is to the benefit of government, society and industry.CITATION:Corder, G D and Bangerter, P J, 2018. Balancing the benefits and impacts of future copper demand – climate change and arsenic, in Proceedings Life-of-Mine 2018, pp 17–19 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 25, 2018

By Molloy GR, Eaton RA

The crusher development programme for 7ft Super Extra Heavy Duty (SXHD) Symons cone crushers commenced in 1984. The main objective of the programme was to run the crushers at maxi- mum power for the full life of the liners. This would give a finer product sizing enabling grinding and flotation plant throughput to be maximised. The study was conducted along two basic lines of attack, the first main- taining an effective profile through the life of the liners, the second improv- ing the properties of the liners. It has been found that crusher liner life can be extended and crushing efficiency improved by modification of liner composition and profile.

Jan 1, 1988

By Bennet A. G

As part of the construction of the Melbourne Underground Rail Loop it was necessary to construct two 7 metre diameter tunnels, each 100 metres in length, by shield driven excavation through an alluvial valley at Elizabeth Street. The tunnels had a primary support of bolted precast reinforced concrete liner blocks and were excavated with the aid of compressed air. The work was undertaken by the Tunnelling Group of the Melbourne and Metropolitan Board of Works as nominated sub-contractor to John Holland (Constructions) Pty. Ltd. The paper describes some of the problems associated with the construction of the above tunnels and the methods used to overcome them. In particular

Jan 1, 1981

By E Ruhanen, S Kauvosaari, M Kosonen, C Meintjes

The Yara Siilinjärvi plant is located in the central part of Finland. Siilinjärvi is Western Europe's only apatite mine and annually it produces 1 Mt of apatite concentrate, which creates approximately 10 Mt of tailings.At the beginning of 2017, tailings handling in Yara Siilinjärvi was brought to a new era, by replacing the conventional tailings storage facility with a new tailings treatment plant. The new high-density tailings disposal system with two paste thickeners increased the percentage of solids in the slurry from 45–48 per cent to 66-68 per cent, making it possible to deposit as a paste. This extended the life-span of the current tailings storage facility by 15 years; from 2020 to 2035.This paper presents the storyline of the Yara Paste Plant Project. The project began with laboratory testing and then progressed to pilot-scale thickening and beaching trials. After some successful pilot trials, the final process design was implemented. Process instrumentation and automation played a key role in the project, as the aim of the Yara Project was to make the plant operable remotely from the main plant. An advanced control system is needed to maintain process stability and the desired operation point in various operational circumstances.This paper discusses the results from the Yara site since the new tailings treatment plant commenced. Some of the main points are that the operation has been running consistently with an underflow solids content of 66-68 per cent, with average beach slope angles of 3.5 degrees in the tailings disposal area. This control system additionally facilitates minimum use of flocculant, which delivers significant savings to operating costs. Robust thickener operation also leads to the trouble-free high-density pumping and high availability of the Paste Plant. During the first year of operation, the plant’s availability has been very good, over 97 per cent.Currently, the plant still has its own staff working there during the daytime, but the Paste Plant is now already operated remotely during the night shifts. The long-term goal is to gradually transition into operating the plant completely remotely.CITATION:Ruhanen, E, Kosonen, M, Kauvosaari, S and Meintjes, C, 2018. Optimising the operation of paste thickening at the Yara Siilinjärvi Plant, in Proceedings 14th AusIMM Mill Operators' Conference 2018, pp 297–310 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018

By LeJuge G. E, McKenzie C. K

Innovative mining and blasting techniques were demanded at the Richmont Mines, Francoeur Mine in Quebec, Canada, by a narrow, shallowly dipping high grade gold ore body. The ore body being mined occurs as a thin tabular deposit varying in thickness between 1.5 and 3.7 metres, and dipping at 36¦. The mine proposed experimenting with open stoping techniques using small diameter drill-holes. The hangingwall required progressive, full face rockbolting after each production blast, utilising a specially manufactured machine which provided access to the hangingwall for both scaling and bolting. Blasted material is mucked from the stope by scraper and hoisted directly to surface without benefit of primary crushing.

Jan 1, 1992

The uptake of nickel into the lattice of pyrrhotite,Fel_oS has been studied experimentally in the temperaturerange 200 DC to 760 DC. Nickel from both aqueous solutionsand salt melts diffuses rapidly into the sulphide latticewith ,an accompanying rel~ase of iron into the solution ormelt. The rate of uptake of nickel and its diffusion intothe sulphide lattice have been followed ,by opticalmicroscopy and by analysis with an electron probe microanalyser.Some geological consequences of this phenomenonaffecting the distribution of nickel in rocks associatedwith nickel-iron sulphide ores are discussed.

Jan 1, 1980

Faced with low prices and weak demand in an oversupplied market, the Australian coal industry must seek to further reduce its costs. The paper examines minesite competitiveness of the open cut coal industry in Australia with some references to the coal operations of M.I.M. Holdings Limited. The make-up of F.O.R. mine costs is analysed in order to identify where efforts should be directed to maintain competitiveness. The scope for mine site improvements through changes to working practices, the application of new technology and cost management is examined.

Jan 1, 1987

By Harris RW, Wood BR

At any given time, the tidal force subjects massive regions to a spatially uniform load. The deformation of any large structure due to these forces is proportional to the elastic properties of the structure. In this aspect, the tidal force applies a load in a manner similar to that of a large-scale testing machine. Any anomalies in the measured tidal response must reflect alterations in the average elastic response of the massive structure. In the present work, tidal tilt measurements obtained in the wall of a large dam are used to infer changes in the response of the dam to applied loads. In particular, it is found that the dam response has changed by approximately 13 percent, on average, for two monitoring periods separated by 5 years. It is possible that these changes were produced by the different volumes of water in the dam for the monitoring periods. The tidal measurement technique can also be applied to monitor changes In the average structural response of large underground and surface masses relevant to coal and metal mines.

Jan 1, 1992

By D Xiong, G Xu, L Yao, F Wang, Y Duan

The goal of this project has been to digitise and use drill parameter data from rotary drilling (measurement while drilling; MWD) for a more effective planning of the blasting process in surface mines. A more accurate and reliable digital drilling and automatic hardness identification technology was developed, which includes both a hardware and software system. In the aspect of hardware, we designed a positioning, navigation and hardness perception terminal system which consists of a global positioning system original equipment manufacturer board, programmable logic controller and sensors of measuring major parameters, and a wireless data transmission system which combines digital blasting platform and wireless transmission facilities. In the aspect of software, we developed the navigation software of locating blastholes using LabVIEW and C++, and the blasthole design software using AutoCAD ActiveX (C#) technologies. This new technology is applied at Jiangxi Dexing Copper Mine, and initially realising the digitisation of drilling and hardness identification in blasting zone.CITATION:Duan, Y, Xiong, D, Yao, L, Wang, F and Xu, G, 2015. Advanced technology for setting out of blastholes and measurement while drilling, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 593–598 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

Filter aids are currently used in many industries to increase filtrate clarity and filtration rates. In other industries filtration could be improved if accept- able filter aids could be obtained cheaply. The present paper describes a simple thermal process for making filter aids from coal, outlines the effects of coal properties and major operating variables, and discusses the properties of satisfactory products. Several possible variations in reactor design have been used experimentally, involving fluidized beds of carbon or inert material, reaction of the particles while entrained in air, and a combination of entrainment and fluidization. The limits imposed on product yields by the composition of the parent coal are considered in relation to a range of Australian coals and one New Zealand coal; and the effects of temperature, residence time, and reactant flow rates have been studied in relation to product yields and characteristics.

Jan 1, 1969

I offer some comments which might complement the valuable recent paper by De Angelis et al (1987), on the newly discovered nickel-copper deposit at Radio Hill.The authors have accepted subdivisions and correlations by Hickman (1977, 1983) although they are disputed (Fitton, Horwitz and Sylvester, 1975; Horwitz, 1979; Horwitz and Guj, 1986).Also, in my opinion, more plausible correlations of the Sholl Belt with Whim Creek Belt have been shown, but not discussed, in Hudson and Horwitz (1986, Figure 1). Our suggested correlations and subdivisions have appeared in publications and reports which are not readily available, but it is gratifying to note that many of the observations and conclusions of De Angelis et al are consistent with our conclusions of the Whim Creek Belt.The units of the Sholl Belt (of Hickman, 1983), between the Sholl Fault (Shear Zone) and the overlying Mt Bruce Supergroup to the south, equate well with units of the Whim Creek Belt. A basalt, characterised by an abundance of vesicles and similar in many ways to the Wararnbi Basalt of Fitton, Horwitz and Sylvester (I975), is well developed at the base of the succession, particularly in the southern part of the area (Figure 1). It is overlain by acid tuffs (locally metamorphosed, such as at Whundoo Mine) and associated acid and mafic lavas, similar to those of the Mons Cupri area. The mafics in the succession are marked by the absence of the numerous cherty sedimentary intercalations, such as the Marble Bar Chert, which occur in the Warrawoona Group; and they also lack the intense chertification that is prevalent in all parts of the proven areas of Warrawoona Group rocks.The Whim Creek Group is overlain, locally unconformably (two to three km east of Mount Negri), by the Negri Volcanics which include here the Louden Volcanics (unit Abu of Hickman, 1977), (Horwitz, 1979). The negri volcanics are an alternating sequence of variolitic and quench textured lavas not dissimilar to the highest units of the Sholl Belt (Figure 1). They range from high-Mg basalt to tholeitic andesites (Glikson et al, 1986, pp 79 and 84). The whole succession of the Sholl Belt is estimated to be of the order of four km in thickness, more consistent with the two km thick (Horwitz, 1979, Figure 1) Whim Creek area sequence than with the much thicker Warrawoona Group sequences. The Whim Creek Group (including the Negri Volcanics) is considered to be a widespread grouping (Fitton, Horwitz and Sylvester, 1976; Horwitz, 1979; Horwitz and Guj, 1986) which is prevalent in the northern part of the Pilbara Craton. It is considered by these authors to include the Mallina Formation turbidites of the trough area of Ryan (1965). One component, the Mons Cupri Volcanic, is about 2.95 Ga (Richards and Blockley, 1984). Between the Sholl Fault and Egina, the Whim Creek Group is intruded by large ultrarnafic to granophyric ills of the Millindinna Complex (Fitton, Horwitz and Sylvester, 1975), dated at 2.860 ± 002 Ga by Gulson and Korsh (1983) near the Sherlock River (south side of Caines Well Granite area). The Millindinna Complex has been equated to the same magmatic episode as the layered complexes of the Sholl Belt by Fitton, Horwitz and Sylvester (1975, p 20).

Jan 1, 1988

By S Ellis

In January 2008 Chirano Gold Mines Limited committed to expansion of the Chirano Gold Project from its existing design capacity of 2 Mtpa ROM ore to a new design value of 3.5 Mtpa. In addition to increased throughput, the design had to contend with increasing ore hardness and competency, while at the same time make cost effective use of existing equipment with minimum disruption to existing production. The solution adopted involved some novel approaches including tertiary crushing and operation of the SABC circuit in overflow ball mill mode and parallel elution with a common acid wash column. This paper describes the approach taken to the design of these elements to achieve a cost effective and safe capacity expansion.

Aug 8, 2011

By A Muhairini, M Eggers, J Smith, H Baxter

Detailed geochemical analysis of cored and non-cored drill hole data was used to characterise and model the Cenozoic detrital valleys of several deposits within the southern Pilbara region, Western Australia. The purpose of this modelling was to better characterise and understand the relationships between the various geotechnical units comprising mixtures of rock and soil for the purposes of slope stability and depressurisation studies.This paper presents data from several valleys where geological, geomorphological and climatic processes have resulted in the deposition of heterogeneous detrital rock and soil sequences. Seven primary detrital units are recognised as occurring within all the valleys studied, suggesting that the geological processes involved in the erosion and deposition of the units were widespread. Geochemical assessment of cored and non-cored data suggests correlatable geochemical signatures can be recognised for each of the units; however, local variability in the groundwater history of individual valleys is demonstrated by late-stage carbonate precipitation recognised both in the core and through the geochemical signatures, which has resulted in alteration of the parent rock/soil material. This paper discusses how the carbonate alteration may lead to improvements in rock/soil mass strength of a clay unit by comparing laboratory strength test samples of the same parent material with varying degrees of precipitate alteration to those with no discernible carbonate alteration. Following from this, correlations with geochemical assay results have been derived, whereby zones of more favourable strength conditions may be modelled through assessing areas of analogous geochemistry.The paper demonstrates how geochemical assessment can lead to improved geotechnical and hydrological modelling for a detrital valley system without the need for significant coring and laboratory testing. This in turn leads to improved confidence in the slope design and depressurisation recommendations for a slope.CITATION:Baxter, H, Eggers, M, Muhairini, A and Smith, J, 2015. The effect of carbonate alteration on detrital mass strength and implications for geotechnical slope design, in Proceedings Iron Ore 2015, pp 429–436 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015