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Common brattice cloths in use in Australian coal mines are compared by permeability measurements. The respective advantages of twill weave and tarpauling* weave cloths are listed, and the improvements to be obtained in the ventilation of a mine by using tarpauling cloths instead of the commonly used twill cloths are stressed. Plastic cloths are widely used overseas and are briefly discussed.INTRODUCTIONThe onset of extensive full-scale mechanization in Australian coal mines during the past few years has increased attention given to the ventilation of working places. Many inadequacies of the present system have been brought to light and not the least of these is connected with the use of brattice cloth, both in directing the flow of air around the face and in acting as a temporary sealing mechanism. A well-constructed line of brattice will only provide fair ventilation for a distance of 100 ft. Beyond this point the volume or air reaching the face falls off rapidly.Some of the shortcomings associated' with the use of brattice cloths are:1. Hurried installation, necessitated by a rapid advance, often results in poor workmanship with, consequently, an excessively high leakage rate.2. High places caused by falls of roof are difficult and time-consuming to seal.3. Curtains, in lines of brattice crossing transport routes, are difficult to maintain.4. Lines of brattice interfere with rock-dusting and clean-up of fine coal.5. Repair and maintenance of brattice consumes much...

Jan 1, 1959

ADDRESS BY THE PRESIDENT OF THE INSTITUTE (MR. J. G. SYMONS) IN PRESENTING THE MEDAL TO LAURENCE CHARLES BRODlE-HALL, C.M.G.The Institute Medal is awarded to a select band of people who have rendered great service to the mining industry and the community. Tonight it is my privilege to present the 1976 Institute Medal to one of our members, Mr L. C. Brodie-Hall, C.M.G.Laurence Charles Brodie-Hall, as chief executive in Western Australia for Western Mining Corporation Limited (WMC) from 1958 to his retirement in 1975, had a profound influence on the company's growth and development which had a significant influence on the prosperity of the State of Western Australia and, in turn, Australia.Following the company's decision in 1952 to diversify from gold mining, he took a leading part in the exploration and development of the bauxite deposits in the Darling Ranges by a subsidiary company, Western Aluminium N.L., and the subsequent formation of Alcoa of Australia Limited, the development of the first long term export contract for iron ore from Western Australia, the development of the nickel deposits at Kambalda and the subsequent establishment of a nickel refinery and nickel smelter in Western Australia.

Jan 1, 1977

By D James

Fletcher Challenge Limited through its subsidiary Grampian Mining Co Limited has carried out an ore evaluation of one of New Zealand's largest known deposits of ilmenite located at Barrytown on the West Coast of the South Island, New Zealand. The ilmenite is located in a beach sand environment which has previously been mined for gold. Two analytical techniques were developed to quantify the resource. Considerable difficulty was experienced in this phase of the evaluation due to the presence of major inclusions within the ilmenite grains. Wet and dry concentration circuits, utilising spiral, wet magnet, high tension and plate electrostatic separators have been designed to produce ilmenite from the ore. Studies to utilise the titanium content of the Barrytown ilmenite have been made. Recent work has been directed towards a titanium dioxide pigment process.

Jan 1, 1986

The Greymouth Coal field is situated on the West Coast of New Zealand's South Island and has been mined for coal for more than 120 years. The area covered in this paper is within the Rapahoe Sector of this field and contains >200 million tonnes of low ash, low sulphur, bituminous rank coal. Paper No 6, presented to the 19th Annual Conference of the New Zealand Branch of The Australasian Institute of Mining and Metallurgy in Christchurch in August 1985 by R G Bowman, explained 'A Geologist's View' of the 'Economic Potential of the Greymouth Coalfield', and describes previous geological assessments of the Rapahoe Sector.

Jan 1, 1989

A Robust Chemically Enhanced Electrostatic Separation Technology Physical separation processes such as gravity, magnetic and electrostatic separations are extensively used in heavy minerals separations. Electrostatic (aka High-Tension) separation facilitated by the conductivity differences, in particular, is used for separating rutile from zircon. Although electrostatic separation is effective, it is not efficient. It suffers from separation efficacy issues owing to sensitive variables such as humidity, surface contamination, particle sizes and the temperature of the feed and other equipment parameters. The variations in the process conditions especially with humidity, temperature of the feed and the mineralogy and surface impurities can cause significant reduction in the separation resulting in production rate losses and product quality issues. Cytec Industries has developed chemical enhancement technologies for electrostatic separation for rutile -zircon separation from the heavy minerals. The major advantage of our technology is its higher separation efficacy in the first pass, substantial energy savings and most importantly its ability to do separation at room temperatures. The bolt-on nature to the existing electrostatic also an added feature that reduces the capital expenditure significantly. The separation efficiency between rutile and zircon was increased as much as 8 - 11 per cent compared to control. It is possible to extend the chemical enhancer technology to problematic feeds and other mineral systems that are not easily amenable to conventional electrostatic separation.

Sep 13, 2010

Large GDP increases in the Pacific Rim countries have been accompanied by similarly large increases in demand for oil products. In the case of residual fuels, this demand has been tempered by the substitution of other energy products such as coal or gas.In the region's developing and newly industrialised nations, it has not been possible to make the very large investements in infrastructure which allow other energy sources to be used for transportation. As a result, GDP growth has been mirrored in the demand growth for automotive fuels. Other non-sustitutable products such as lubricants have also benefitted by the region's GDP growth.The combination of a number of years of sustained growth, coupled with increasing quality requirements is now stretching the upgrading capacity of the region's refineries. If, as seems likely, the region continues to enjoy a high GDP growth rate, then this will be accompanied by increasing reliance on finished products coming out of the Middle East. The owners of the most simple form of refinery in which crude is simply distilled and the naphtha reformed into petrol will face major capital investments. If they decide not to bear this cost, they will face increasing problems in selling their surplus residual fuel oil at an economic price. Quality will become an increasingly important issue. Not only in the well publicised areas such as unleaded petrol, but also for products such as lubricants which play a major role in the efficiency of modem equipment. Quality of service such as hours of opening, ease of access, and service station facilities will also become increasingly important as the oil companies use these to attract customers and gain brand differentiation.

Jan 1, 1990

By G Small, A Lazamanana, C Greet

When conducting gold leach tests on free milling gold ores which method is the best, bottle rolls or the stirred beaker test? Recently, a client requested that gold leach tests be conducted using the stirred beaker methodology. When asked why, because the laboratory was set up to conduct tests using the bottle rolls technique the reply was that the stirred beaker leach test would replicate the plant more closely. Not wishing to upset the client, the instructions were followed. However, the opportunity was taken to complete additional tests so that the two leach procedures could be compared. Further, this comparison was completed on two different gold ores as well as a number of different grinding media types.This paper provides a description of the two laboratory techniques employed, and presents the results of these parallel tests. Interestingly, the assertion that the stirred beaker methodology more closely replicated plant performance was not validated. In fact, the results obtained using this procedure were noticeably different from those observed in the plant, with lower recoveries and significantly higher cyanide consumptions. The bottle rolls test however more adequately replicated plant performance in terms of recovery and cyanide consumption. The reasons for this are discussed in the paper.CITATION:Greet, C, Lazamanana, A and Small, G, 2015. Bottle rolls versus stirred beaker leach testing – which is best?, in Proceedings MetPlant 2015, pp 188–196 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 7, 2015

By A C. Carter

The increasing need for alternative energy sources as well as the less clearly perceived but equally increasing demand for non-fuel minerals has resulted in extensive exploitation of near surface deposits. Many such deposits have depleted reserves and mining corporations are increasingly turning their attention to deposits, with thicker overburden, less competent materials, steeper dips and more complex structure. These deposits pose mine layout, geotechnical and equipment problems as well as the need for large outputs to achieve economies of scale. The paper describes the major problems and operational solutions for such deposits using continuous excavation and transport equipment.

Jan 1, 1980

By A H. Clemens, T A. Moore

This paper discusses a number of technical issues related to marketing coal. It outlines how the results of research undertaken in New Zealand and overseas can help producers address a range of technical factors that impact on production costs and marketability. The paper also discusses trends in coal utilisation for power generation and how new technologies may require coal with different characteristics. Research and development into options for CO2 sequestration are discussed including carbon storage in forests, and removal of CO2 from flue or fuel gas in power stations, and its disposal.

Jan 1, 1997

By S Watson, L Martinez

Mine projects are complex opportunities that demand a constant assessment of uncertainty, ie risk and upside potential. This is because the value of a mine project is typically influenced by many underlying economic and physical uncertainties, such as metal/mineral prices, metal/mineral grades, costs, schedules, quantities, and environmental issues, amongst others, which are not known with much certainty at the beginning of the project. But, is uncertainty an enemy or an ally of the mine planner/analyst? To answer this question, this paper first assesses and elaborates upon the general concept of uncertainty. It then looks at the different sources of uncertainty in a mining project, such as the orebody, costs and product price uncertainties, and their effect on the final project value. Next, a general?review?of current mine evaluation techniques highlighting their limitations when dealing with uncertainty is made. Finally, an extended evaluation and risk management framework that addresses the existing uncertainty in the (greenfield/brownfield) mine evaluation process is proposed. One important characteristic of this framework is that it uses and manages uncertainty in order to generate additional value to the project; this is done through operational and managerial flexibility, which allow mine planners to minimise/maximise project risk/upside-potential giving a more realistic estimate of the projectÆs market value - this is shown in practical and simple examples occurring at different stages of a mine project, such as exploration and operation. Final conclusions are provided at the end.CITATION:Martinez, L and Watson, S, 2012. Uncertainty - An important source of (additional) value for mine projects, in Proceedings Project Evaluation 2012 , pp 131-140 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 24, 2012

Adhesion of Escherichia coli onto Oxide Minerals - Extended DLVO Theory and Flotation Behaviour

Sep 13, 2010

The An Shan iron ore deposit is the biggest low-grade oxidised iron deposit in China. Over the past ten years, about 120 SLon verticalring-pulsating high gradient magnetic separators units have been installed in An Shan to process oxidised iron ore. This paper describes how several plants have upgraded their old technologies to new technologies with SLon magnetic separators as the key equipment for controlling tails grades, including using reverse flotation as the key technology for iron concentrate cleaning, These plants have been modernised with beneficial results at low cost.

Jan 1, 2009

Validation and Simulation of Optimised Compressive Crushing Ores and aggregates are used in countless applications all around in the society. The frequent and escalating usage of these natural resources requires efforts aimed at not only making do with what is available, but also undertaking actions to improve the production yield and the processes involved. This strive to improve the performance and efficiency of existing crushers and crushing processes has brought about research concerning optimisation of crushing plants as well as theoretical optimisation of crushing. Previous work shows that different applications and different materials require different compressive crushing in order to accomplish a theoretically optimal size distribution. These optimisation results, obtained by genetic evolutionary algorithms and evaluated with so called fitness functions, convey the theoretically optimal number of compressions and their corresponding compression ratios. Presented in this paper are thus some laboratory crushing tests, which are conducted in order to validate a set of previously optimised crushing sequences. More specifically, interparticle crushing sequences are carried out in a Piston-die testing equipment, where samples are sieved between each compression. The subsequent analysis of these results shows good correlation with model predictions, which combined with a comparative study between presented optimisation results and measured data from a real crusher indicate a significant potential for improvement. However, before redesigning crushers according to what is theoretically optimal, the resulting impact as well as the effects on the outcome of a crushing plant must be examined. Crushing plant simulations using the software PlantDesigner« are consequently performed. Models of existing crushers are altered, resulting in changed particle size distributions from some of the crushers in a crushing plant. Thence, it is concluded that significant gains can be made in terms of capacity, process yield and energy consumption.

Sep 13, 2010

Developments in the technology of explosive production and deliveryallow a greater amount of flexibility in rock fragmentation by blasting. The rock fragmentation efficiency of an explosive is currently given by a rating which is determined by the explosive manufacturers using proprietary formulae and methodology. Hence, comparison of explosives from different manufacturers may be misleading. Modeling of explosive energy, using a thermochemical code such as CHEETAH provides an objective standard by which the likely performance of different explosive formulations can be determined. Such modeling can be used for optimisation of explosive composition to match specific rockfragmentation objectives.

Jan 1, 2001

The Resource Management Act 1991 (RMA) and the Crown Minerals Act 1991 (CMA) both came into force on 1 October 1991. The purpose behind RMA was to integrate the existing laws dealing with town and country planning, land subdivision, water and soil, minerals and energy resources, coastal management, air pollution and noise control into one omnibus Act. Originally, there was a section in RMA dealing with minerals. However, this section was taken out of RMA and a companion piece of legislation - namely CMA - was passed with RMA.

Jan 1, 1994

In November 1969, New Zealand Steel Ltd pioneered the commercial use of the SL/RN solid fuel direct reduction process to make sponge iron as a feed material for electric arc furnaces. Serious process problems with the use of green balls and coal injection were progressively overcome. The process was developed by New Zealand Steel along a radical route, of feeding the fine grained raw ironsand concentrate and coal directly to the kiln. Contemporaneously with this development of direct reduction, steelmaking process innovations were made that enabled the arc furnaces to operate successfully with the high volumes of acid slag. The further expansion of New Zealand Steel's primary steelmaking capacity to replace the currently imported hot and cold flat rolled products is under consideration. The requirement to produce about 600 000 tonnes of steel slabs will be an opportunity to further modify iron and steel making plant and processes to optimise the economics. The conceptual and preliminary engineering selection of options is described.

Jan 1, 1980

By H Arvidson, C Morley

Reconciliation has become very topical over the last ten years but how do we distinguish what is good practice, and even more importantly, show how it adds value? Reconciliation at Anglo American has received support from the very top of the company and this has enabled success in the design and implementation of a range of processes, reporting activities and actions. Focus has been on full Mine Value Chain Reconciliation (MVCR) from Resource to Product and on proactive cross-functional engagement. A standardised set of reconciliation definitions and relationships are used at all mines across the company to diagnose planning and performance issues. Results are formally presented in an efficient dashboard format, accompanied by a concise narrative to communicate what has been learned and what is being done to correct, improve or change practices. Importantly, effort has also been made to sustain MVCR by embedding good practice and quantifying the benefit of reconciliation explicitly via linking results to value.This paper sets out the lessons learned from the past two-years’ journey, highlighting areas where good practice has been defined and achieved. A ranking for quantifying reconciliation confidence over time is presented as a means of putting results into context and continuously improving the reconciliation process. Finally, a solution to define the value that can be derived from reconciliation is described, detailing how cross-functional personnel meet monthly to review results and implement actions that are tracked in terms of value creation.CITATION:Morley, C and Arvidson, H, 2017. Mine value chain reconciliation – demonstrating value through best practice, in Proceedings Tenth International Mining Geology Conference 2017, pp 103–116 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

By P Landeros, D Benado, J Cornejo, A Pinochet, C Caviedes

In 2005, El Teniente mine began preconditioning the primary rock mass by hydraulic fracturing (HF). The major perceived benefits of this process are a decrease in the magnitude of the expected maximum seismic event and improved cave propagation. In addition, HF has resulted in new information on the propagation pressures of each fracture. Previous studies have attempted to relate propagation pressure to minor principal stress or confining stress.Considering the spatial continuity of propagation pressure and the significant quantity of collected data since the incorporation of the HF technique, minimum requirements for geostatistical modelling have been reached, permitting robust estimates inside the representative volume with acceptable errors (Cornejo, Muñoz and Rojas, 2012; Cornejo and Landeros, 2013). These results are then used to identify zones with higher magnitudes, which are mostly related to more complex geotechnical zones (intrusive and major faults) and caving singularities, making it possible to estimate the spatial extension of these zones.Finally, these results are integrated with other geomechanics aspects to support risk analysis of the mining plan.CITATION:Cornejo, J, Landeros, P, Benado, D, Caviedes, C and Pinochet, A, 2016. Geostatistical modelling of hydraulic fracturing pressures at El Teniente Mine, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 183–190 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By R H. Sillitoe

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. Geological concepts are employed routinely in porphyry copper exploration at the area selection, prospect appraisal and deposit definition stages. Regional, district-scale, deposit-scale and laboratory-based concepts can all play a role, with the resulting porphyry copper models providing templates for the integration of geochemical and geophysical responses and interpretations. Of the 19 concepts and parameters selected for brief discussion, those relating to subdivision of porphyry intrusions, understanding of diverse and commonly complex alteration-mineralisation patterns and lithocap characterisation are undoubtedly the most influential in exploration. Several of them are of particular importance because of their role in promoting grade development. Additional belt-, district- and deposit-scale features are currently little used but hold promise, whereas others have less practical value but help in underpinning the evolving porphyry copper genetic model.CITATION:Sillitoe, R H, 2015. Recent advances in porphyry copper geology and their exploration utility , in Proceedings PACRIM 2015 Congress, pp 35–44 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By D Prior

The Australian mining industry is a significant contributor to the nation’s greenhouse gas (GHG) emissions, and like any industry, it must make efforts to reduce these. Medium- and long-term strategies will include the replacement of diesel engines with alternative energy sources, but what can be done in the short-term to reduce diesel consumption and hence CO2 emissions? Haul trucks are identified as the major contributors of CO2 emissions in the mining fleet and this paper focuses on firstly identifying what drives haul truck emissions and secondly, discussing what is the role of the Fleet Management System (FMS) in reducing these. A key enabler of this is having a robust fuel consumption model within the FMS, and I describe how this may be done. Besides novel approaches to incorporating fuel consumption (CO2) management into truck assignment algorithms, this paper also describes how the FMS can be used to implement and manage procedures and policies to reduce haul truck emissions.

Jun 22, 2022