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The New South Wales coal industry is a highly mechanised well organised industry which has developed from an annual production of slightly less than 13 million tons in 1950 to over 33 million tons in 1969. Although continuous miners were not introduced into the mines until 1950, by June 1969 the percentage of coal won by these units was 87.3. The paper describes mining conditions in the various coalfields of the State, their complexities and problems and how these have been dealt with. The introduction of fully mechanised longwall faces has presented a challenge which has been accepted and descriptions of systems in use are discussed. Major expansion of the industry is anticipated to meet the requirements of the growing Australian steel industry, for local power generation and to meet the increasing demands of overseas markets.

Jan 1, 1980

By Thornton D, Esterle J, La Rosa D

Control of blast fragmentation has a significant impact on coal mine profitability. Two approaches for the characterisation of coal blastability, particularly in terms of fines, are presented. Both approaches were implemented for the predictio

Jan 1, 1998

A four monthly period was analysed for each retreating longwall face which indicated that output increased from 1140 tonnes/day for Longwall 1, to 1620 tonnes/day for Longwall 2 and to 2090 tonnes/day for Longwall 3. An output of 2500 tonnes/day should be achieved from the new Longwall 4, largely due to the improved tailgate corner design and despite a continuing lump coal problem. The evolutionary trend is a feature of longwall mining; the evolution occurring both with mining and mechanical design at the colliery itself and with the longwall equipment offered by manufacturers. The trend is towards simplicity, increased strength and capacity, simplified maintenance and increase relia- bility.

Jan 1, 1976

By Svensson J

The nickel segregation process is one of the methods for treating nickel oxide ores. In this process nickel oxide ores are heated together with a small amount of the carbonaceous reductants and halides to about 800-950¦C. The reduced nickel segregates onto the surface of the carbonaceous reductants in the form of metallic particles which are recovered by magnetic separation or flotation. Pilot plant tests for the extraction of nickel from nickel oxide ores have been made using nickel segregation process by means of a new roasting installation which is called the "Mechanical Kiln" (2.5m~ x 3m,') with autogenous heating. Nickel oxide ores containing about 2.5%Ni were mixed with 2.5%CaC12 and 2.7%coal, and continuously charged into this installation at the rate of 60kg/h in continuous operation for 30 days per trial.

Jan 1, 1980

By Tamura S, Maekawa M, Nagai C, Deguchi M

Heavy fuel oil has been injected into blast furnaces in order to reduce the coke rate, to improve productivity and to control the furnace heat condition. However, in the first oil crisis at the end of 1973, it became necessary to develop an injection technique of new fuels into blast furnaces to reduce oil consumption. In Kobe Steel, Ltd., it was thought that the injection of a coal-oil mixture (COM) into blast furnaces could be developed in a shorter time than pulverised coal injection. The development of this technique was under- taken in 1974, and COM was injected through two tuyeres of the No.3 blast furnace at the Kobe works in 1977 and 1978. In addition, in order to study the combust- ibility of COM and the phenomena in the tuyere zone, the development of a gas sampling method was under- taken in 1975. In this paper, the results of the injection tests and gas sampling tests are reported.

Jan 1, 1981

Territory Iron has seen fit to revive the old Frances Creek iron ore mine some 30 years after it ceased operations in AustraliaÆs Northern Territory. The key to this revival has been the changes that have happened since market forces, infrastructure limitations and a cyclone combined to force its closure. As it breathes life into this old mine, the Company is serious about its responsibilities to its shareholders, to its workers, to local and regional communities and to the environment. This paper addresses how Territory Iron has approached technical, operational and regulatory issues that apply in Australia. Some insight may be gained into the myriad of tasks that mining companies face to revitalise an old mine. These tasks vary from employing the latest exploration tools, best practice drilling, sampling and modelling of orebodies, optimisation of pit designs and schedules, maximising product value by blending, optimising infrastructure usage and minimising capital and operating costs. All of this has to take cognisance of commercial, environmental and other issues including Native Title.

Jan 1, 2007

By M Littlefair, D Gribble, R Rounsley, I Te

Low-density explosives (LDE) have applications where the explosive properties of ANFO are not well matched to the rock. In particular, rocks that are of low strength and/or well fragmented in situ. Dyno Nobel Asia Pacific (DNAP) has developed a new LDE, BlastLiteTM, which can be used as a cost-effective replacement for ANFO with excellent detonation characteristics. The product is based on ANFO with the addition of a bulking agent. The key to the product lies in the ability of the bulking agent to form a homogeneous blend with ANFO without the need for any emulsion matrix to bind the product together. This results in an LDE of low cost and high weight strength compared to existing commercial LDE products. The product has been trialled extensively and has proven to provide results that are equivalent to, and often better than, ANFO with reduced powder factors. This paper details the laboratory development and results of field trials for DNAPÆs LDE solution: BlastLite.

Jan 1, 2004

By Sagrabb T

In a company's quest for financing the development of a new mine, it will make calls on stockbroking houses and banks. The choice of the best-fit broker or banker is of great importance, and in the case of the miner, this is a house that has an intimate understanding of the mining industry, particularly one that has a solid staff complement of personnel with operating mine experience at a senior level. The most important document that the company will present to support its financing request will be the Feasibility Study. It cannot be too strongly emphasised that this document must be absolutely comprehensive and cover items including: (a) Geological review; (b) Resources and reserves; (c) Mineability; (d) Mining schedule; (e) Metallurgy; (f) Process plant description; (g) Infrastructure and services; (h) Management and operations; (i) Environmental and social impact; (j) Capital costs; (k) Operating costs; and (1) Financial analysis. The elements listed above represent major topics and require a great deal of expansion in the body of the document. Rothschild Australia Limited assists its client companies by supplying a detailed framework so that they will be in a position give the bank the information it needs to complete its technical `due diligence' study within a mutually agreed time. The client company will advance its position markedly if it uses well-known, reputable consultants to either complete or assist with the various aspects of the Feasibility Study. Such an approach will give the potential financier confidence that the company has taken a professional and unbiased attitude in determining the feasibility of the property in question. Most small- to medium-sized mining companies, both within Australia and overseas, will prefer, or will find it mandatory, to request a project funding package rather than opt for a corporate loan. This is because the company either does not want to tie all of its assets to the performance of one project, or that it is a one or two project company with no other substantial assets and is therefore unable to obtain a corporate loan. Upon receipt of the Feasibility Study, the bank will use the data supplied by the company in its cash flow analysis to build its own financial model. The purpose of this is to examine the timing of

Jan 1, 1994

The Hunter Valley Rail Project (HVRP) represents most of the coal producers using the Hunter Valley Rail System in NSW to haul coal to the port of Newcastle. This system carries over 70 per cent of NSW's coal exports, comprising over 30 per cent of total Australian coal exports. Hunter Valley coal is the largest export industry in NSW, and one of its largest export growth opportunities. However, the industry is under intense pressure in international markets from existing and new coal producers and from other energy sources. Whilst potential growth in demand is substantial, particularly for thermal coal in Asia, excess world supply has pushed prices down, and this underlying trend may well continue. The industry has lost international competitiveness and as a result, investment has dropped 44 per cent over the last two years. The industry must be rapidly structured to compete and attract investment on the basis that these pressures will continue. Substantial productivity improvement and cost reductions must be made for the industry to regain competitiveness, otherwise growth will not occur and the industry will decline, with serious implications for the Australian and NSW communities. The introduction of internationally competitive rail freight rates is an urgent and essential part of this process. It is the key objective of the HVRP.

Jan 1, 1995

Daily geological mapping of the Panguna porphyry copper/gold system since mining began in 1971 has provided a good basis for resource estimation and mine planning as the mine and estimation methods have advanced. Geology defined during evaluation and early mining has been substantiated and many smaller features have been better defined or identified. Breccias, pebble dykes, major structures and location of lithology contacts important to short term planning and long term pit slope stability have been defined. Correlation of copper and gold with breccia zones is quite striking and was not fully appre- ciated at the end of evaluation. Pit mapping geology, and diamond drill geology and assays, are now routinely added to a Geological Data base on computer, which forms the major geological data base for modelling the deposit. Geology from diamond drill logging, updated by pit mapping, and assays from diamond drilling updated by blast hole assays have been incorporated in a 45 bench deep 486 000 block computer based block model which forms the basis for long and short term planning. The introduction of pre-concentration scre- ening, based on the distribution of mineralisat- ion and fracturing, puts more emphasis on the definition of grade distribution at low concent- ration and on structures in the rock. Geostatistics is now used for resource estimation and has produced acceptable estim- ates. but these need to be refined, particularly in peripheral, low grade areas of the deposit.

Jan 1, 1987

The granulites and related "dry" igneous rocks tend to be passed over during exploration for metals. Preliminary data show that high trace concentrations of Cu, Ni and other metals of economic interest are common in orthopyroxene and some of the other granulite minerals. During retrograde metamorphism of granulites, pyroxenes are converted to amphiboles or phyllosilicates, and significant quantities of metals are released and become available for incorporat- ion into new mineral phases, or may be transported elsewhere. S--rich scapolite is the normal scapolite of granulites. Its retrogression to secondary plagioclase provides much S which scavenges Cu, Ni, etc., from pyroxenes undergoing retrogression, thus producing ore-fluids. A full analysis of a scapolite with 5.10 per cent S03 is given. Beryl is unstable in granulites but the rare Be mineral taaffeite (Al4Pf (Be,Fe)O3) with 5,50 per cent BeO occurs in central Australia as a pale green Tabular mineral easily confused for chloritoid in hand-specimen. Metamorphic differentiation and mobilization of primary ore concentrations are major factors controlling their post-granulite attitude and grade.

Jan 1, 1969

By Dimitrakopoulos R

Ore textures in base metal deposits are an important factor in the liberation of the economic components of the ore, metal recovery and reagent consumption during beneficiation. Optimising the mine profit requires knowing the relationship between ore texture and mineral processing behaviour, and the ability to predict the metal grade and the ore texture at a suitable scale. A new method that generates distributions of mesotextures for any mining block size or shape is proposed and includes: I . establishing a protocol for acquiring mesotexture data: 2. measuring the mesotexture spatial correlations using a multi-texture variogram; 3. generating multiple simulations of mesotextures; and 4. upscaling the simulations to generate the expected mining block/stope mesotexture distributions. Models of the ore textures built using the proposed methodology can be used to assess resources and reserves, enhance ore/waste discrimination and predict the metallurgical behaviour of parcels of ore.

Jan 1, 1997

I am very pleased to be here at this seminar on carbon-in-pulp (CIP) technology for the extraction of gold as I am always interested to hear about any new development in any aspect of gold ore processing. We can expect to learn a great deal from the papers to be presented over the next few days. It is not my purpose to give a detailed description of the CIP process nor to give a complete historical review. However, in this opening address it was thought appropriate that I should mention some historical features and some technical factors to set the scene for subsequent papers. HISTORICAL NOTE Table 1 shows some interesting dates of the use of carbon in gold metallurgy in Australia. Mount Morgan used carbon after chlorination TABLE I Carbon precipitation in Australia 1891 Mount Morgan 1917 Yuanmi mine (Edmunds) 1934 Sons of Gwalia (Edquist) 1975-1980 Various pilot plants and small companies 1980- Various large and small plants

Jan 1, 1982

By Kramadibrata S

Over the years many attempts have been made to develop a means of assessing the excavatability of rock. Most of them are based on an empirical rating system while some authorities still propose the use of seismic velocity as a direct predictor of the rippability of a rock mass. On the other hand there are a number of classical models which have been developed to define the cutting force required at the pick or tooth of continuous miners.While these methods have been applied with various degrees of success to the design of excavation systems there is no generally acceptable method of defining the excavatability or cuttability of a rock mass in terms of the machine power required to generate a particular rate of production.The authors have attempted to overcome this deficiency by recording the intact and rock mass properties at a number of surface mines where continuous miners were in use and to use this data to examine the relationships between the relevant dimensionless groups developed from a dimensional analysis of the problem.The results obtained are encouraging and it appears that this new approach to the problem could lead to civil and mining engineers having a means of predicting the cutting power required to excavate rock at a given rate at any site.While this paper does not include a review of past work it refers to a number of key publications which will give the reader an excellent introduction to the subject.It is important to point out that the research work reported in this paper is part of a doctoral research project at Curtin University of Technology on the Influence of Intact Rock and Rock Mass Properties on the Design of Surface Mines. One of the major objectives of this project is to explore the possibility of developing a technique for predicting the excavatability of rock in surface mines at the design stage.This paper therefore commences with a brief reference to the continuous surface miners in use at the test sites followed by some original work by the authors in applying Dimensional Analysis to analyse the macro-performance of mechanical excavators. Following an analysis of the experimental data the authors validate the wider use of the model by referring to its successful application in predicting the power required to excavate rock by continuous surface miners at other sites.

Jan 1, 1995

By Jamsa-Jouneia SL, Lahteenmaki S

Sophisticated control systems require sufficient and reliable information from the process to be controlled. At the Pyhasalmi concentrator two novel measurements, a particle size indicator (PSI) and a mill level monitor (MLM), have led to significant progress in the control of the grinding circuit. The PSI and the MLM measurements have brought additional information from the process. The PSI has been an absolute prerequisite for determining the overall grinding circuit efficiency and the design of the integrated grinding and flotation control system. The MLM measurement has enabled studies on the volumetric filling of a mill to be utilised for maximising the mill throughput. The paper describes the operation principles of the PSI and MLM devices and the additional process information received. The results of a metallurgical pre-control audit are discussed and finally the design of the integrated control system is outlined.

Jan 1, 1993

There is a Chinese saying-may you live in interesting times. Certainly we do tod.a~our mining professions. We are, of course, totally dependent on a' healthy mining industry for the chance to practice our chosen professions, and for our Institute.Let us look at one of the more interesting facts. The mining industry now accounts for some 50 per cent of Australia's exports.This massive earning of foreign exchange is the key to keeping our increasing overseas debt in check. Furthermore, mineral production..including petroleum, saves us a large amount of foreign currency by providing essential minerals, including energy minerals, for local consumption.With such fundamental inputs to our economy, any primary school student, any child in fact, should be able to see that the mining industry and mining professions are very important to our nation. Yet the average citizen is unaware of this simple fact as they enjoy their high standard'of living and think that we are still living in the lucky country.Therefore, it is most interesting to me that the average citizen, and most of our politicians, seem to hold mining and miners in low esteem. I use the term miners to describe all those important people, like us, who work in the mining professions, and are employed by, or are dependent on, the mining industry.So why are we miners in this paradoxical situation of doing wonderful works, being the backbone of the country, and yet being held in low regard by the very community we underwrite.Truly-it is interesting-or did the Chinese mean intriguing?It is indeed paradoxical that we are the rare people who open up the land, borrow small parts of it for a relatively short time to harvest the mineral crops, then return it to the community for other uses; and when we return the land back to the community at large it should be in better shape than when we started. There will be infrastructure - roads, airstrips, supplies of water and power, parks and housing-all left behind after mining.These benefits to the community are ignored while our critics focus on the small scars on the landscape which sometimes cannot be healed at reasonable cost; and yet, if we allow time, nature usually heals the small scars anyway. Look at New Zealand, particularly the Coromandel Peninsula which was intensively mined and logged; now it is covered with secondary growth and stark pine plantations. Remember that mining scars are infinitesimally small when compared to urban sprawl or clearing of land for farming and grazing, or highways, or the area of most national parks.Thus, miners are important citizens economically, and we are the majority of the few who actually practice the principles of multiple land use.What are the consequences of our image? They are serious in that the poor image we seem to project, discourages many people from becoming involved in, or supportive of, our industry. This brings me to my theme for the year: Students, Education and Communication - the Key to our Future.

Jan 1, 1987

By Batterham R. J

Some developments in copper, lead and zinc extractive metallurgy which have gone in to production or seem to be close to production scale are described with emphasis on why these innovations have been adopted.Mineral processing operations are now using: automated quantitative mineralogy,high capacity fine crushing equipment, ò fine grinding equipment, andcolumn cell flotation.Extractive metallurgy plants are using:ò bath smelting of concentrate at various scales, and ò flash converting of copper.Hydrometallurgical process developments are slower to make a commercial impact. Concerns about ability to handle impurities in the feed and production of saleable by-products are often major hurdles.An expression for the probability of implementing the first example of a new development is presented.

Jan 1, 1992

By S Basu, S L. A Gowravaram

CaF2 has been a common constituent in a wide variety of welding fluxes, including those used for submerged arc welding (SAW). The widespread use of CaF2 stems from its role in lowering the liquidus temperature as well as the viscosity of the molten slag that covers the weld pool. However, the harmful effect of fluoride evaporation from molten flux, on the environment as well as the health of the users is becoming increasingly evident over the years. This has led to increasing attention towards reducing the CaF2 concentration in the fluxes. The fluoride-free formulations face the challenging requirement to maintain the thermo-physical properties (viscosity, liquidus temperature etc) like those observed in fluoride-containing fluxes. In the present work, three fluxes with compositions in the CaO-MnO-SiO2-Al2O3 system have been identified as promising alternatives to the CaF2-rich fluxes. However, the thermo-physical properties of any such flux need to be comparable to CaF2-based commercial SAW fluxes before it can be adopted for regular use. The single hot thermocouple technique (SHTT) has been used by several researchers in the past as a tool for observing the melting and solidification characteristics of fluxes. This device has been developed in the present work and is used to characterise the melting behaviour of the fluxes. The measured solidus and liquidus temperatures from SHTT were compared with the results from differential thermal analysis (DTA) and simulations using the FactSage™ software for a comprehensive understanding. In spite of having a slight deviation in the measured values from the multiple techniques, the results obtained from these multiple methods show that the selected compositions could be potential CaF2 free alternative welding fluxes.

Jun 19, 2024

By Shoobridge PH, Firkin GR

The Imperial Smelting Process blast furnace (ISF) of the Sulphide Corporation Pty Limited zinc/lead smelter at Cockle Creek, New South wales, has in recent years greatly increased its consumption of low grade feed materials, and as a consequence has experienced periods of unstable furnace operation. Routine examination of production sinter, including softening characteristics and micro- examination, showed that the problems had been caused by an increasing silica content in sinter. The silica entered a low melting point glass phase containing calcium and lead oxides. The relative volume of this phase increased until it formed a continuous matrix in the sinter structure and this made the sinter more likely to soften at lower temperatures. Premature softening caused loss of operating stability in both the shaft and hearth of the ISr. The required sinter structure for ISF smelting was found to consist of a network of intermeshing, refractory crystals which provided skeletal strength for sinter lumps even after the glass phases had begun to soften and melt. With an understanding of the importance of microstructure and softening temperature of zinc/lead sinter and the progressive identification of those factors in sinter production which affect the microstructure, a significant improvement in stability of operations has been possible.

Jan 1, 1980

lbis new concept in geology is introduced by a reinteipretation of the Archaean stratigraphy of the greenstone belts of the Yilgarn Craton of Western Australia. Evidence is presented to show that the recorded Archaean succession of the Eastern Goldfields Province is composed of two distinct groups of mafic/ultrarnafic and felsic igneous rocks which, together with sediments, form alternating sequences represented by Cycles 1 to 4; Cycle 5 consists entirely of sediments. Recorded stratigraphy for the Murchison and corre1atives of the Southern Cross Subprovinces conform to this pattern. The five basic components are referred to as Unit 1 to Unit 5. A major erosional unconformity between Units 3 and 4 extending across the Craton is identified as a locus of potential major gold occurrence, including fossil placers, where suitable structural situations exist; Units 1 and 3 are identified as potential hosts of gold and nickel deposits; Units 2 and 4 for gold and base metals.

Jan 1, 1994