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Topography, location of coal bearing land and existing built-up areas severely restrict locations for overburden disposal and dumping sites north of the Latrobe River clear of the coalfields are assumed until internal dumping areas can be established.

Jan 1, 1982

Applications of chlorine metallurgy to the extraction of metals often result in the production of volatile metallic chlorides, most of which condense directly to a solid phase at one atmosphere pressure. A stirred bed condenser suitable for th

Jan 1, 1980

By Kanchibolta S. S, Brunton I, Tapia-Vergara F

The Split digital image processing system has been implemented in three Australian mines for analysing the size distribution of rocks from the images taken from muckpiles, conveyor belts and tipping trucks. This paper presents an overview of t

Jan 1, 1998

By Valery W, Morrell S, Loughlin P, O&apos

Traditionally, blasts in mining operations are designed to prepare the in situ rock mass for excavation and transport without much consideration being given to the downstream comminution processes. Blasting is in fact the first step in a chain

Jan 1, 1998

Incremental sampling is defined as a solution to fight segregation, the theory is demonstrated and theoretical and practical aspects are discussed. The number of increments necessary for successful sampling is discussed. As an application, riffle splitter division is reviewed.

Mar 1, 2010

Powered support plays a major role in longwall mining and improper selection may lead to a disaster. While different countries follow different norms, a universal approach is needed to be developed. For this purpose, a computer program C-ALPS

Jan 1, 1998

The degree of ionicity-covalency of complex compounds is discussed here as a prospective criterion for selection and purposeful synthesis of sulfhydril and oxhydril collectors. Theoretical predictions of flotation behaviour were confirmed by flotation of a number of ores.

Jan 1, 2005

New Zealand China Clays operata a plant at Matauri Bay, Northland for the benefaction of hallosite clay. Production is several thousand tonnes per year of which about ten per cent per year is supplied to an expanding export market.

Jan 1, 1978

By Gillies A. D S, Supriyadi

The landed cost of coal to the international customer is a major parameter which determines market competitiveness. Rail, port and shipping charges represent 30 to 50 per cent of landed costs for Australian mines selling to Asia. This prop

Jan 1, 1994

The foundation of our industrial welfare lies in the success of our primary industries, and, so far as mining is concerned, it is hoped that for many years it will be a most important primary industry in Western Australia.

Jan 1, 1927

This paper attempts to put into perspective the implications of the legal disclosure requirements for promoters and consultants when making statements concerning ore resources and reserves. The need to take account of non-technical as well as technical factors is highlighted.

Jan 1, 1987

Thank you for asking me to address you. The topic may sound formidable. Those of you with determination to go somewhere in your careers will understand that by taking geoscience, mining and metallurgy courses as students, you are declaring your intere

Jan 1, 1994

Problems encountered in the design, construction, acceptance, commissioning and early operation of the electrolytic zinc plant at Port Pirie are reviewed. Recommendations based on the author's experience are made for proper control of each phase of the development of new plants.

Jan 1, 1971

A method for determining the relative degree of oxidation of concentrate samples was established, and various surface-active materials and protective systems were examined as oxidation inhibitors. Sodium oleate was-the most effective of the materials tested, and a plant trial

Jan 1, 1963

By Rogers J. F, Bird A. C

The establishment of vegetation for dust control on tailings dams at The Zinc Corporation, Limited and New Broken Hill Consolidated Limited (ZC/NBHC) is outlined. The evolution of practices and techniques employed is described and the problems encountered are discussed.

Jan 1, 1983

By I Coombes, M Trim, Y Sun, M McRae, A Spiegl, H Lagger, A Amon, P Barraclough, M Villeneuve

The Brisbane Airport Link Project (AirportlinkM7) includes the design and construction of more than 12.5 km of tunnels, with the Kedron interchange including four ramp tunnels that intersect with mainline tunnels and result in caverns with spans of up to 26 m. These caverns are in highly variable ground conditions with less than 35 m of cover underlying residential neighbourhoods and commercial properties. The Kedron caverns were constructed using the sequential excavation method (SEM). Owing to complex geometry and excavation sequence, the caverns were designed based on numerical modelling methods, including both two- and three-dimensional models. These numerical methods were used to develop a suite of support types with excavation sequences for the expected range of ground conditions. A combination of methods that included in-tunnel monitoring (convergence monitoring and extensometers), probe holes, endoscope probes, face mapping and ground settlement measurements were used to verify performance of the tunnel support systems and to select and refine the appropriate support system for each section of the caverns. The construction monitoring data indicated that numerical modelling can provide a good basis for predicting the performance of large-span underground openings in highly variable ground conditions. This paper presents a comparison of the performance of the caverns predicted by state-of-the-art numerical models and the actual measured performance.CITATION:McRae, M, Villeneuve, M, Trim, M, Sun, Y, Barraclough, P, Spiegl, A, Amon, A, Lagger, H and Coombes, I, 2014. Brisbane Airport Link Project – design and construction of the 26 m span Kedron Caverns: comparing monitoring data with the design, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 295–306 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By K Peters, C McKenzie

New Zealand has an established history of gold production beginning with the gold rushes of the 19th century in the Coromandel, Nelson/Marlborough, West Coast and Otago regions. Despite this, the number of significant modern hard rock gold operations has been limited in recent years due to a lack of sustained exploration capital and not limited geological prospectivity.The New Zealand Government is actively encouraging explorers to invest in New Zealand through a series of targeted promotional visits, more importantly through the acquisition of precompetitive regional geophysical data. Data collection has been completed over the prospective Northland epithermal district and a large portion of the South IslandÆs west coast that is prospective for both orogenic gold and intrusive related gold.Analysis of new data has been an important component in aiding the generation of exploration targets from prospectivity modelling. Determining the prospectivity of an area involves reviewing all the available data and analysing it with respect to the most up-to-date mineral system model for the mineralisation style of interest. Using the weights of evidence modelling approach, the most prospective areas for epithermal gold-silver, orogenic gold and intrusion-related gold have been identified. The key exploration parameters relevant to each mineral system are first represented spatially and then statistically combined into a single prospectivity map. New potentially economic deposits could be found by focusing exploration on targets identified from these models. The prospectivity modelling approach can greatly reduce the risk involved in mineral exploration.CITATION:Peters, K and McKenzie, C, 2013. New Zealand gold potential - using mineral prospectivity modelling to evaluate gold-bearing mineral systems in an underexplored country, in Proceedings World Gold 2013 , pp 479-486 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 26, 2013

By E de Necker, F D. I Hodg, L-M Cruywagen

The acid mine drainage (AMD) situation at three opencast collieries in the Witbank Coalfield, South Africa, was evaluated from different perspectives. Twenty-seven test pits were dug into the spoils of these collieries to characterise the in situ conditions of spoils of varying age. Detailed static testing was done on surrounding drill holes and additional samples were taken from the test pits. Selected samples were tested using different techniques, namely ABA, mineralogy and kinetic tests. Groundwater monitoring boreholes from the areas surrounding these spoils were also used for characterisation. The ABA results compared favourably with the in situ determinations; acidic test pits proved to be potentially acid-generating from ABA, even when the samples had neutral paste pH. Kinetic test results showed these samples to yield low pH leachate over the test period. In several of these results, the theoretical depletion of neutralising potential and the onset of acidity were well matched. NAG pH-values and final observed water chemistry corresponded for the cells predicted by ABA to acidify, but compared poorly in cells that did not acidify. Results from the non-acidic spoils were consistent with the in situ observations. Alternative kinetic test methodologies were also employed. Duplicate samples were tested in humidity cells and in aerated trays that were manually wetted on a regular basis. Results from these tests showed an excellent correlation. Detailed mineralogical determinations using XRD and XRF were used for comparison to the ABA and, in some cases, humidity cell results. These comparisons show that the ABA results are consistent with the results expected from the mineralogy. The conclusion from these assessments is that ABA, in most cases, provides information that can be correlated to the field, mineralogy and to humidity cells. The use of multiple techniques leads to a higher degree of confidence in the use of the data.

Jan 1, 2003

By R Mann, R Prasad, S Vink, V Nanjappa

The level of salinity that various aquatic organisms can tolerate without incurring any adverse effects is dependent on several environmental and evolutionary factors. These factors include the relative concentrations of different types of dissolved salts in the water that makes up their habitat, the regimes to which organisms are exposed to waters of differing salinity levels (including naturally derived variations), the degree to which an organismÆs life history stages have adapted to salinity, an organismÆs ability or behaviour to avoid adverse levels of salinity and an organismÆs capacity for osmoregulation.Release of saline water into rivers of the Fitzroy catchment has created concern about the impact on aquatic organisms. Not only is salinity itself a stressor on organisms but different ionic compositions will moderate the effects. Ecotoxicology experiments were conducted using artificial saline water based on mine water chemistry using sensitive macroinvertebrates collected from the catchment, as well as a range of laboratory organisms in accordance with the ANZECC and ARMCANZ (2000) guidelines. The 95 per cent ecosystem protection value calculated from species sensitivity distribution derived from the commercial tests was estimated to be ~2.0 mS/cm. For the protection of 99 per cent of the species the salinity has to be reduced by more than 50 per cent to 0.91 mS/cm. The electrical conductivity (EC) values, derived by commercial testing and species sensitivity distribution in this study suggests that salinity contaminant trigger values previously developed using a referential approach for protection of aquatic ecosystems from saline mine water releases in the Fitzroy may be conservative.CITATION:Vink, S, Mann, R, Nanjappa, V and Prasad, R, 2013. Determining the impacts of salinity on freshwater organisms, in Proceedings Water in Mining 2013 , pp 149-154 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 26, 2013

By B Beamish

The concept of a ‘critical velocity zone’ in the longwall goaf environment for the development of a spontaneous combustion event has been supported by numerical modelling. However, there is no experimental data available for Australian coals to show ventilation effects on the self-heating incubation behaviour of broken coal in the longwall goaf. A preliminary study using incubation testing has been completed on three high volatile bituminous coals (A, B and C) with R70 self-heating rate values of 3.86°C/h, 3.15°C/h and 2.09°C/h and moisture contents of 11.3 per cent, 3.9 per cent and 4.7 per cent, respectively. Mass to flow rates used in the adiabatic oven reaction vessel have been selected to be indicative of a sluggish, natural air leakage and medium ventilation environment. Under a sluggish ventilation flow rate all three coals incubate to thermal runaway in minimum time frames of 2.8–3.1 years, 34–42 days and 79–95 days, respectively. When the ventilation flow rate is increased to natural air leakage, coal A with the highest R70 value and highest moisture content selfheats to 28°C above mine ambient temperature before heat loss takes over due to moisture evaporation. However, both Coals B and C at this flow rate incubate to thermal runaway in a shorter time frame than under sluggish flow. At the medium ventilation flow rate, only Coal B incubates to thermal runaway, albeit after a significant extended period of time. These results show how important it is to determine the heat balance between the coal intrinsic reactivity (as indicated by the R70 value) and moisture content. The results also have implications for the possible location of the ‘critical velocity zone’ and subsequent hotspot development and migration.

Oct 12, 2022