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By Kewu W

Kaolin used as an industrial mineral, especially that in the paper-manufacturing industry, must be of fine size, with high brightness, a low impurity content, and good crystal shape. However, in most kaolin deposits there are various impurities which have a very bad effect on the quality of the kaolin. Therefore, it is necessary to remove these impurities from kaolin ore. Owing to their similar surface properties, the separation of kaolin and iron oxide minerals, especially microkaolin and iron oxide minerals, has been regarded as difficult. The iron oxide minerals often intergrow with kaolin in fine and complicated forms, such as thin films, which make separation difficult. In order to overcome this difficulty, many workers have suggested various treatment methods and obtained great success. Based on research work by Fuerstenau (1980), Huang, Li and Hu (1984), Hui and Wei (1991), Shergold (1978), and Zambrana et al (1974), we have investigated a two-liquid flotation technique for iron removal from kaolin and obtained some success.

Jan 1, 1993

By Xaykhamphoune, Ward B

Draglines have been used exclusively for primary overburden stripping at the German Creek Mine complex in central Queensland, where coal has been extracted from a series of ten open cut pits working seams of the German Creek Coal Measures. Due to the dip of the seams, most of the pits have now reached the limit of current economic viability and the emphasis has switched to underground extraction using longwall methods and to a new area of open cut reserves in the nearby Rangal Coal Measures at German Creek East. This area is characterised by weak Tertiary overburden, relatively steep dips and low strength intraformational shear planes at the top and bottom of the coal.The first pit, with a maximum depth to coal of 15 m at the low wall, avoided any major slope failure through use of scrapers to excavate the boxcut and dump the spoil away from the low wall. However, this method was not considered economically viable for the second pit where low wall depths reached 44 m. Following geotechnical investigations the boxcut was divided into a number of zones depending on depth of cover, dip and thickness of Tertiary clay. Slope stability was assessed for each zone using several analytical techniques to ensure that dragline mining would be acceptable. Slope design parameters incorporating various stabilisation techniques, notably an updip trench backfilled with competent spoil to form a low wall buttress prior to excavation of the boxcut panel, were successfully integrated into the mine plan after careful consideration of the complex scheduling to minimise rehandle.

Jan 1, 1992

By Weatherhead J, Grounds J

The Nabarlek Uranium Project located in Arnhem Land in the Northern Territory of Australia was a small high-grade deposit which was the first uranium mine brought into operation following the extensive Commissioner Fox Inquiries into uranium mining during the late 1970s. The operation is almost complete and decommissioning plans have been prepared. This paper reviews all phases of the water management and tailings disposal for the project and compares results with design predictions.

Jan 1, 1988

By Stewart A. M, Price D

This paper presents recent findings concerning longwall caving mechanisms relating to Australian mining conditions and their effect upon longwall support requirements and behaviour. The findings are based on a program of intensive hydraulic support monitoring in a variety of Australian mining conditions coupled with geotechnical observations.

Jan 1, 1992

By D Kepert

It is the role of the exploration geologist to create wealth through the discovery, delineation and characterisation of economic mineralisation. This requires a critical depth of geological understanding.Unfortunately, the resource industry is well known for its cyclic nature. Many of the current generation of workers have only ever experienced the boom of the ‘super-cycle’ and are only just discovering the negative side to the business. For the case of the geologist and especially the exploration geologist, the magnitude of peaks and troughs are usually amplified and may become destructive to all parties. During the uptime a healthy stream of exploration good news becomes the staple diet of company releases, in particular those of junior companies attempting to bolster the share price. The geological knowledge and experience gained thus forms a significant and integral part of the value and therefore, future of a company. On the downturn it is often viewed that geologists are a luxury, an optional extra and a burden on the bottom line with companies entering a period of memory loss and myopia.Retention of geological knowledge however remains critical as projects, companies and cycles mature. Beyond exploration per se, this knowledge becomes both fundamental in de-risking and commercialising an asset (through development or divestment) and in positioning the company for cyclic or counter-cyclic opportunities.The growth and retention of this knowledge base is difficult to quantify in terms of direct value but becomes one of a successful resource companies greatest assets. At worst, its loss can lead to millions of investors’ funds wasted on missed opportunities, drilling, or poorly designed plant and mine.But the rocks are around for the longer haul and pay little notice to the vagaries of the scurrying of Man.This paper reflects on some of the authors own observations through 25 years of iron ore exploration, in why it is critical to always rigorously question the prevailing geological (mis)understanding and the technical and commercial benefits which that may bring, and looks forward to the future.CITATION:Kepert, D, 2015. Geology – the affirmative case, in Proceedings Iron Ore 2015, pp 285–298 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

This paper briefly reviews the history of mine haulage trucks. It reviews producti- vity limitations with respect to size or speed. Changing haul requirements once again create the need for more flexible mechanical drive power transmission equipment. The new equip- ment however is designed to provide extended life between overhauls as compared with previous mechanical transmissions.

Jan 1, 1981

By K M. Watling, F M, G K. Parker

Surface enhanced Raman scattering (SERS) spectroscopy at surfaces under electrochemical control has been applied to elucidate the adsorption of thiol collectors. SERS spectroelectrochemical studies at coinage metal electrodes have been carried out on ethyl xanthate and three iso-xanthates, O-isopropyl-N-ethylthionocarbamate, 2-mercaptobenzothiazole, diisobutyl- dithiophosphinate and butylethoxycarbonylthioura. For each collector, adsorption occurs via charge transfer to form a metal-sulfur bond and, in situations for which the reversible potential of the formation of the bulk phase is known, at underpotentials.

Jan 1, 2005

The Golden Plateau Mine is located at Cracow in central Queensland, 350 kilometres north west of Brisbane. The mine was operated by Golden Plateau NL as an underground mine from 1933 to 1976 with a total production of 18.5 tonnes of gold. Prod

Jan 1, 1994

The problems encountered with the introduction and use of Isanol underground are described. Significant direct as well as indirect savings have resulted from the use of Isanol. Field studies have shown that the concentration of common gases released during detonation is considerably lower than with conventional nitro-compound type of explosives.

Jan 1, 1977

By Garrigan J. S, Oakes I

Current operating practice in a plant commissioned some five years ago to treat ferritic zinc plant residue by the "Jarosite" process is described. Major problems overcome include obtaining reliable pH measurements at 100¦C, prevention of scale build up in spent electrolyte heaters, blinding of jarosite filter cloths and the deposition of gypsum in filter presses.

Jan 1, 1977

For many crushed aggregate producers will the finest fraction minus 4 mm represent a problem. The fine material will fetch a much lower price than the coarser products, and may even be difficult to sell in some markets. The blasting operation will strongly influence the generation of fines after both blasting and crushing. Drill hole deviation together with the drill hole diameter, powder factor and velocity of detonation are the most important blasting parameters with regard to the generation of fines. Drill hole deviation is often ignored, and many operators will just reduce the drilling pattern in order to avoid hard bottom and an excessive number of boulders. The paper presents a technical and economic analysis of how drill hole deviation will lead to an increased generation of fines in crushed aggregate production. The analysis shows that the loss of sales revenues will be much higher than the extra costs for drilling and blasting caused by compensating for drill hole deviation by putting in more holes.

Jan 1, 1999

By Johnson N. W, Quast K. B

Over the years there have been occasional references in the literature to the activating effect of cyanide in galena flotation with xanthates. These have usually been associated with the processing of lead-zinc or copper-lead-zinc ores. Bubble contact curves for the pure galena-xanthate system show a flotation edge at pH 10.4 independent of sodium cyanide concentration which was thought due to hydroxyl ion, not cyanide ion.Flotation tests were conducted on samples of Mount Isa lead-zinc ore using varying concentrations of sodium ethyl xanthate and sodium cyanide. At low collector concentrations, galena recovery kinetics improved with sodium cyanide addition, and the higher the cyanide concentration, the higher the galena recovery rate. At higher collector concentrations, galena recovery rate was independent of sodium cyanide addition.For a given collector addition, the lead grade-recovery curve shifted to an improved position with increasing sodium cyanide level. For the same recovery there was an increase in the lead grade with increased sodium cyanide addition, and this increase was most dramatic at high sodium cyanide concentrations.The presence of sodium cyanide during the grinding of Mount Isa ore caused surface passivation of the iron sulphides and possibly the sphalerite.These sulphides, therefore, reacted with less of the oxygen present in the pulp, hence more oxygen was directed to the surface of the galena. This resulted in an enhancement in the total amount of xanthate adsorbed on the galena that is reflected in the improved flotation response of that mineral.

Jan 1, 1990

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 Coombes J, Richards W. L

The objective of this paper is to illustrate, in a practical way, how both geologists and mining engineers can use conditional simulation to add value to their decisions. Inherent assumptions, requirements and essential components of condition

Jan 1, 1998

By Lumley G. I, Duffy W. J

The risk involved with incorporating new/unfamiliar technology into mines has, in the past, largely been evaluated by the supplier of the technology. The implications on safety and productivity has been accepted as part of the process of `getting up and running'.This has changed. As companies see the lost productivity and accidents actually costing significant dollars, risk assessment is becoming an important part of the implementation of new equipment. Regulatory authorities are also seeing the preventable incidents and in some cases are now requiring a risk assessment to be undertaken on new equipment at a Mine.

Jan 1, 1992

By Membrey W. B, Partridge A. C

Lower transportation costs, improved handling and better utilization efficiency are some of the reasons that make low moisture coal product desirable. There has been considerable interest in the development of effective coal dewatering techniques to achieve this result. One avenue of considerable merit for enhancing dewatering processes is by modification of the surface chemistry of the coalwater slurry system by chemical means, resulting in better performance of existing equipment. This paper reports the results of an investigation of the utility of surface active agents in the enhancement of fine coal dewatering. A large variety of proprietary dewatering agents have been studied in relation to their efficiency in enhancing the dewatering of a number of Australian coals. Properties of particular coals that make them amenable to improved dewatering by particular chemical agents have been identified. Surface studies, including surface tension and zeta potential measurements as a function of surfactant concentration, as well as dewatering assessments, were used. Particular attention was paid to filtration, but the results could be applied to other dewatering systems.

Jan 1, 1989

By Dyne GD

From experience in the design and operation of power station combustion facilities in most mainland Australian States, involving a wide range of black coals and lignites, and in the specification and procurement of coal supplies for power station use, techniques for the optimisation of coal resource development and power generation utilisation have been developed to ensure compatibility between characteristics of the selected coals and power station design. These techniques include computer data bases for resource data handling and computer simulation of coal-fired boilers for determining coal property cost effects. Data Base Systems allow results of coal analyses to be efficiently handled, to assist in the review of the relevance of resource data to the coal sections proposed to be mined and the coal fractions proposed to be marketed. Data Base Systems also facilitate the marshalling of coal quality data into basic utilisation format to enable a proper utilisation review and analysis of the certainty and scatter of coal properties. Computer simulation of the effects of different coal properties on the capital and operating cost of power stations is achieved by establishing conceptual design parameters of the major items of plant to relate the variations in coal specification to equipment size and type. Variations in power station budget costs can then be determined using the computer model for variations in coal specification.

Jan 1, 1983

By Witkowski A

I have the pleasure to present 6 excellent papers in this section all of major relevance to the mining environment of today where competing social, legal and monetary interests and their often complex interaction require serious consideration. This is particularly true today where huge fluctuations in commodity prices makes mining a perilous undertaking while the world increasingly are becoming aware of the serious threat that mans activities has on his environment. The 6 papers deal with such complex issues as safety in an underground environment; How to protect sensitive wetlands well into the next century; The enormeous waterproblems in China and conflicting dewatering/water supply needs; Disposal of contaminated water in sensitive areas and the dynamic interaction between mining companies and legislation.

Jan 1, 1988

By Woodcock J. T, Sparrow G. J

Activated carbon particles obtained from a number of Australian CIP operations were examined with an optical and a scanning electron micro- scope and an electron microprobe. External surfaces, and polished sec- tions through individual particles, were examined with special reference to materials on the surface and to calcium and gold distributions. Photographs are presented of surface contamination of the particles by salts precipitated from the pulp such as calcium carbonate (calcite), calcium sulphate (gypsum), and a magnesium salt; ore minerals such as quartz, hematite, pyrite, arsenopyrite, pentlandite, and various alumino- silicates; and other substances such as grinding media and a fungus. Calcite was very abundant but the other materials were less common. Contamination in the interior of carbon particles was almost exclu- sively calcium carbonate, and extensive contamination extended to the centre of some particles. A possible mechanism for the formation of cal- cium carbonate inside the carbon particles is noted. Gold X-ray dot maps of sections through carbon particles indicated that gold was distributed throughout coconut shell carbons and that although gold was more concentrated near the outer surfaces of extruded peat carbon particles, it was also present to depths of at least 500 ¦m. The gold distribution throughout the carbon particles was similar to that rf alrit~

Jan 1, 1988

By Robbilliard K. R, Floyd J. M

The problems facing the metallurgical industry from the viewpoint of the range of unacceptable residues, flue dusts and slags currently produced from the electrolytic zinc process, electric arc furnace scrap treatment, and blast furnace operation in lead smelting and the Imperial Smelting Process (ISP) are addressed. The application of the Ausmelt technology is discussed and analysed for the pyrometallurgical treatment of zinc plant residues, steel plant flue dusts and lead blast furnace and ISP slags, as well as the more complex issue of smelter modernisation to avoid production of zinc plant residues in the future. Processes developed from pilot work are described and indications of the economics of treatment of electrolytic zinc plant neutral residue and jarosite are given.

Jan 1, 1993