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By Gottlieb P, Sutherland DN

The paper describes a method of making quantitative mineralogical measurements on many of the major lead/zinc orebodies in Australia. The work was done using QEM*SEM. It was found that a relationship betwen phase-specific surface area and particle size, when plotted in a suitable way, gave a straight line with slope related to the grain size of the mineral in question. The method provides an excellent way of differen- tiating between minerals in existing orebodies and, consequently, an easy way to establish a comparison between a new prospect or orezone and current operations.

Jan 1, 1988

Patterns of successful metallic mineral discoveries in Australia are analysed for the last three decades. A trend towards more discoveries of poorly expressed and blind ore- bodies is evident and can be expected to continue. Discoveries using traditional and conceptual geological techniques have proportionally declined but are expected to continue at a significant level for a decade or so. Improvements in the quality and numbers of geological exploration models and in the quality of available basic geoscience data have aided successful discovery in recent years. Although some orebodies for the Year 2001 have already been found maintenance of a strong mineral inventory demands that more and better geological models are applied. Empirical models need to be improved by critical multi- disciplinary integrated studies of mineral occurrence at all scales. New models can and will be developed by various means. If application of these models is made with all the innovation, initiative and unorthodoxy that can be mustered then new discoveries will result. Greater attention to the surface expression of orebodies will also lead to new discoveries. Review and follow-up of old data in the light of new concepts will provide yet another discovery route.

Jan 1, 1981

By Reynolds JO

This contribution by. The Australasian Institute of Mining and Metallurgy has three main thrusts. First, an Institute (and industry) view on academia and the need for more entrepreneurship at top academic levels, second the need to lift our technological game, and third, professionalism and the perceived role of mineral industry education. While I will deal with each of these separately they are of course inter- related and can be brought together under the frequently used, but insufficiently practised title, "communications". First then, The Institute and industry view of academia. There are some academics in the audience and I imagine they may wish to reply to my remarks with an academic view of industry. That is not unreasonable. Like all human institutions, academic institutions vary in quality and characteristics. Some are successful and some less so. Some historically are well renowned. Others that were once successful schools have declined. Lesser known schools have grown into prominence. What is it that sets apart 'good' highly regarded schools from those that are not so well regarded? It comes down to one main ingredient - "leadership". The strong mining schools in the past 100 years have been strong because they have had outstanding and clearly identified leaders. Strong clearly identified leadership has always had rapport with, and the support of the industry. The two go hand- in-hand, each nourishing and supporting the Other.

Jan 1, 1986

This paper describes a steam outburst in a metal mine which occurred in December 1992 in Japan, resulting in two fatalities. The outburst occurred just after blasting in a heading face 600 m below surface (SL-50 m), 1664 m from a mouth of the mine. The scale of the outburst was large and the fragments of the outburst spread up to 34 m from the face, the total volume of the outburst was estimated to be 206 m3. The outburst materials were mostly clay originated from the typical surrounding rock of sulfide ore and basalt. The shape of the larger outburst fragments were slabs with a thickness of 10 to 20 cm. The victims were found in a main ventilation air shaft, 175 m and 380 m from the face, respectively. The mine mainly produces copper, lead and zinc. The face was ventilated by a 560 mm diameter duct with a fan and the strata temperature of the rock was estimated to be in the range of 120 to 140¦C. There is a famous hot spring near the mine. A thorough investigation into the unprecedented accident was made including an on-site inspection and investigation of rock characteristics in laboratories.

Jan 1, 2005

By McNicol J. H

Using a small scale laboratory pilot plant a series of tests have been conducted with the aim of investigating the influence of the zinc/acid ratio on the efficiency of zinc electrodeposition from an acidic sulphate solution. The results have shown that current efficiency is increased as the zinc/acid ratio is increased with no evidence of an optimum zinc/acid ratio. However the choice of a zinc/acid ratio for full scale operations must be a compromise between other parameters, spent electrolyte acidity and power efficiency, which also impact upon plant performance. The effect of various impurities has also been monitored and antimony, nickel and tin have been shown to be deliterious to current efficiency.

Jan 1, 1989

By Bowden MW

Sintering of lead-zinc concentrates is practised by Sulphide Corporation to provide both desulfurised lump sinter feed, for simultaneous reduction to zinc and lead in the Imperial Smelting Process blast furnace, and sulfur dioxide gas for sulfuric acid manufacture.Moisture control of feed mixes is of paramount importance in the sintering operation and improvements in this area have realised increases in overall plant performance.

Jan 1, 1985

By I Kolomaznik

Each technological process can be reduced on the transport networks, and namely on the parametric networks and the non-parametric ones. The parametric networks are created by the piping, electrical cables or channels. The non-parametric network is created by the ways, suspended grooves, trackages and also by the belt conveyors or other conveyors for continuous material transport. If we reduce the technological process on transport networks, then, by the creation of these networks models and their mutual interconnection we obtain the model of the whole technological process. The model can be understood as the universal one, without exaggeration, because it is valid for any technological process. However, for us the mining production process is important what represents the mining and transport of raw materials under the support of the ensuring system. In this contribution one of the first attempt is described, and namely how to connect the parametric network which has been already worked out very properly with the non-parametric network what is presented in this contribution by the transport line of belt conveyors.

Jan 1, 2003

By Ellis WK, Greenwood-Smith R

A nuclear technique for the analysis of copper in bulk materials has been developed and successfully field tested at Mount Isa Mines Limited. The technique utilises the gamma-ray resonance scattering process. A bulk analyser based on this technique gives a rapid and accurate measurement of the percentage by weight of copper or nickel aver- aged over a large mass of sample, typically 20 kg. The only sample preparation required for accurate analysis is crushing to -2.5 cm. At Mount Isa over 100 mineral samples covering a wide range of rock types and copper contents were analysed. Bulk analyser assays and chemical laboratory assays agreed closely for underground pillar-extraction and geolog- ical chip samples, conveyor belt samples, and finely ground samples from the ore concentrator. For the concentrator samples, the root mean square deviation between bulk analyser and chem- ical laboratory assays was 0.06 wt.% copper. The chemical assay errors for these samples were about 0.06 wt.%

Jan 1, 1975

The source and origins of the hydrothermal fluid of orogenic, or quartz-vein lode-gold deposits remain uncertain and disputed: Resolution would likely have a significant affect on exploration strategy. The gold-carrying fluid is interpreted to be a low-salinity mixed aqueous-carbonic fluid of near ambient pH and redox state, that may be derived either magmatically through crystallisation of granites at depth in the crust or through metamorphic reactions in a range of rock types. Classic isotope and geochemical tracers of fluid source have not differentiated these possibilities and have produced conflicting conclusions. Mass balance calculations show that fluid composition will be modified by wallrock reaction between source and deposit, and tracers should not be expected to give clear indications of fluid source. Fluid oxidation state can also be modified along flow paths. Tracers should be interpreted with care and with view to possible modification. Modelling of full flow paths and examination of the hydrothermal histories of proposed source rocks may be alternative approaches to determining fluid source.

Jan 1, 2002

By K Matsui, T Sasaoka, S Kubota, Y Yosh

A large amount of wastes from the preparation plant is produced. The properties of these wastes vary depending on the mineralogical contents of the mother rock in which the coal is embedded. The waste quality depends on the method of mining and cleaning. The waste mainly consists of clays, quartz, carbonaceous materials, mica, pyrites and so on. About 55 per cent of coal-ash is now utilised and the remains are disposed of at the disposal sites, however, the life of the disposal site is limited. Moreover, it is difficult to find new disposal sites. Therefore, it is requested that the percentage of the utilisation of the coal-ash be increased in every field in Japan. So, it is very much available if the injection material for natural/artificial openings can be applied on the cement that is added to flyash. Among the man-made pozzolans, a flyash is probably the most successful component used in grout injection. When flyash is added to Portland cement concrete, the same kinds of oxides as those of the cement are being added. As an injection component, flyash acts, in part, as a fine aggregate and, in part, as a binding component. However, there is not a substantial alteration of the properties of the original component. From these points of view, in order to clarify to what degree the flyash content affects the properties of the injected grout mixture; different combinations of flyash, Portland cement and water were considered by means of several experiments.

Jan 1, 2003

Modern, high-output, continuous process plant requires heavy capital expenditure and is exroected to achieve a high rate of return upon the investment made, thus its high utilisation is an economic necessity. Downtime is extremely expensive not only in terms of idle capital but also in terms of lost production and revenue. A sound maintenance management system can alleviate the problem of unscheduled stoppages and a key document in the maintenance system is the Work Order because it both initiates work and conveys maintenance control information back to the administrator. This key document must be supported by an information base that provides technical data, job procedures, spare parts, history and costing. To be effective this information must be easily and immediately available to all concerned. Computer technology has developed extremely rapidly over the last ten years and with it a wide variety of on-line computerised maintenance systems. Selection of the most appropriate system for a given industrial plant is not a straight-forward process. Computer requirements for hardware and software must be matched to the requirements of the maintenance system and such matching must be carried out in an ordered and rational way. At Kalgoorlie Nickel Smelter, time was taken to review the existing maintenance system, select, study and test the new computerised maintenance management package and plan its implementation. As a result, the initial target of equipment recognition has been achieved on schedule and within budget.

Jan 1, 1987

By Carter LC

Following the perception by the Groote Eylandt Mining Company of a need to further beneficiate a fines product, and preliminary metallurgical testing to demonstrate the feasibility of such beneficiation, a comparison was made of the various configurations of cyclonic heavy medium separators available. This comparison consisted of (i) a pilot plant test in which a dynawhirlpool (DWP) and a pump fed cyclone were compared, and (ii) a survey of operating plants using the systems under consideration. Little metallurgical difference was found-between the different systems. The gravity fed cyclone configuration was finally chosen based on a particular need to minimise degradation of ore and on a desire, in so isolated a location, to use established and locally supported technology.

Jan 1, 1987

By T Akiyama, J A. de Castro, H Nogami

Blast furnace is a countercurrent moving bed reactor that produces pig iron from iron bearing materials like pellet, sinter or lump ore. The furnace has cylindrical shape and the lump solid materials are alternatively charged onto the top of the furnace. Hot air is introduced through tuyeres that are set on the lower furnace wall. Auxiliary fuels (pulverised coal, oil or natural gas) and raw materials (fine ore or fluxes) are injected into the furnace with blast air from the tuyeres. In front of the tuyeres, coke particles react with oxygen in the blast air and generate carbon monoxide. The hot reacting gas heats up the lump solids and reduces iron oxides in the upper furnace. In the middle height of the furnace, the reduced iron and slag are fused by the combustion heat and form the cohesive zone. The molten iron and slag that are generated in this region trickle down through the packed bed of coke particles and flow into the bottom of the furnace. Therefore, the flows of gas, lump solids and liquids exist at the same time in the lower part of the blast furnace.

Jan 1, 2000

Aspects of the formation, decomposition and acid solubility of zinc ferrite were examined to find potential ways of increasing the recovery of zinc from a calcination process of mineral concentrates. Ferrite can begin to form within 2 hours at 450¦C. while complete reaction can occur after 35 minutes at 700¦C. The nature of the starting materials has a pronounced effect on the rate of formation and below 700¦C. ZnSO4 and Fe2O3 proved to be the least reactive of the materials investigated. It is possible that iron in a mineral admixed h sphalerite can be converted to a relatively inactive form, however, it does not seem possible to prevent zince f formation when iron is in the sphalerite lattice. At the two temperatures examined, 650¦C. and 700¦C, the presence of SO2 in the atmosphere accelerate .e formation of ferrite. Prolonged exposure to such atmospheres, however, caused the ferrite to decompose to ZnSO4 and Fe203. The optimum temperature for decomposition was 650¦C. and it was virtually complete within 2 hours in an atmosphere of 10% SO2 in air. Zinc ferrite was also decomposed by CO at low concentrations, and by heating with limestone at 1000¦C. for at least 2 hours. The solubility of zinc ferrite in acid was influenced by the starting materials used. As both the reaction temperature and the time at temperature increased the acid solubility decreased. The acid solubility was a minimum when the ___i_.. n - I -r~...................c -..... F, fe..i+e --A frn... A01- +^ Z(lo/

Jan 1, 1970

By McKee DJ

Future mineral processing developments will be of two types. There will be a continuation of the advances of the last 20 years including major increases in equipment capacities, the development of reliable on-line instrumenta- tion, the use of digital computers for automatic control, and the greatly expanded use of in-situ leaching techniques. However, there will also be a need for innovations as the industry faces a different set of problems to those involved in cost and extraction efficiency considerations. These new problems include those relating to energy usage, environmental pressures, and the further development of large low grade deposits and small, high grade metallurgic- ally complex deposits. Present technology does not appear adequate to solve many of these new demands. New treat- ment concepts will be required, and the immediate outlook in this regard is not encouraging. A major research and development task in mineral processing over the next 20 years will be to seek out new ideas and develop them, and this must be pursued with imagination and determination. Both the continuation of the present research pro- grammes and the development of new methods will require a steady supply of highly qualified technical personnel. These people are not being produced in the numbers required, and this situation must be urgently rectified.

Jan 1, 1981

The Maddingley brown coal seam at Bacchus Marsh, where mined and bored, tends on the whole to a higher content of volatile matter than the Latrobe Valley brown coals, and this masks the presence of lignitic or earthy coal bands in the bore core analyses. Visits to the Lucifer Open Cut, at Bacchus Marsh, during 1948, revealed, however, a banded condition in the coal seam, as shown in Fig. 1. This banding showed in a face that had been exposed for a considerable period of time, permitting partial drying out and oxidation of the surface coal. The bands consist of different coal types, ,comparable with those found in the Yallournand Latrobe brown coal seams(l).The' light coloured bands in Fig. 1 consist of a buff to light-brown earthy coal of low specific gravity, that closely resembles the pollen coal, that occurs, as similar thin bands in the Yallourn and Latrobe seams. The 40 ft. of coal above the uppermost of these light coloured bands dries out on exposure to a black, closely cracked surface, composed of small dice-like fragments of a lustrous vitrain-like substance, and in every respect resembles the lignitic coal bands of the Yallourn and Latrobe seams.The coal between and below the light-coloured bands develops fewer and more widely spaced shrinkage cracks on drying out, and remains brown in colour and earthy in appearance, resembling the earthy coal of the Yallourn and Latrobe seams.Representative samples were cut of these coals, taking care to exclude surface coal, and analyses were made of them by the Metropolitan Gas Company, through the kindness of Dr. R. S. Andrews, Chief Chemist to the Company...

Jan 1, 1948

By Sheng X. L

The Jurassic coals at Datong are characterised by their strong, massive sandstone and conglomerate roofs which fail suddenly over large areas, crushing pillars and creating destructive windblasts. collapsed areas have exceeded 180,000m2 and windblasts have extended over one km underground and 200m on the surface and have been accompanied by subsidence troughs on the surface. Scientific analysis has researched premonitory signs of caving and the nature of windblasts leading to considerations of alternative mining methods and ways of dissipating the energy of windblasts to reduce their damage and danger..

Jan 1, 1992

In Australia a social impact assessment (SIA) is generally required prior to the approval of a mineral resource extraction or processing projects as a part of the Environmental Impact Assessment (EIA) process. In recent years there has been increased attention on the adequacy of the SIA process applied in major project assessment. Most applications have focused on the impact identification process with little attempt given to the community negotiating power over how impacts will be addressed. The impact assessment tends to occur at a single point in time, with no subsequent re-evaluation or ongoing social impact management and monitoring process. The assessments rarely specify how responsibilities for impacts on communities may be apportioned between project proponents and government, and have been inadequate in dealing with cumulative project impacts. In Queensland, concern about these shortfalls have led to the release of the Sustainable Resource Communities Policy 2008 and requirements for social impact management plans (SIMP) to be developed for each resource development in the State. In this paper a 'pressure-state-response' approach to impact assessment is used to develop an 'impact-response-monitoring-evaluation' (IRME) framework that can be applied to ongoing evaluation and monitoring of social impacts. The framework is applied to coal resource developments in the northern Bowen Basin in Queensland to identify core requirements in a SIMP. The IRME framework is flexible enough to be implemented at various spatial and time scales, for the wellbeing of the local and regional mining and non-mining communities in Australia. The framework can be further examined in other mine developments and could be integrated with the existing mining or environmental protection acts.

Jun 1, 2010

By Hawes GW

Until 1980 copper, lead and zinc sulphide slurries have been success- fully dewatered for rail and sea transport for many years at the Rose- bery site of North Broken Hill Holdings Ltd. utilizing conventional vacuum disc filtration systems. An upgrading and mill expansion program completed in 1981, which also permitted the introduction of ore streams changes, had resulted in difficulties dewatering copper and lead sulphide slurries to comply with transportable moisture limits. Following an extensive investigation which included both laboratory and pilot plant testing a program was commenced to replace the 2 vacuum disc filtration systems with 2 pressure filtration systems for use on copper and lead slurry dewatering and also to retain other existing vacuum disc filters as standby. An analysis of mill operations performance resulted in slurry storage tanks with a capacity equivalent to 20 hours of normal production being incorporated into the project. The pressure filters are mounted above the concentrate stock- piles. A sealed sloping floor incorporating launders is used to prevent any accidental contamination of the concentrate from pipe leakages, spillage, or from water hoses used for clean up purposes around the area. The project was completed in 1985 and operating performance has been better than that predicted from testwork. Equipment availability at 95076 together with the slurry storage capacity provided results in minimal requirement for the standby vacuum filtration system. Some typical operating results are given.

Jan 1, 1988

Basic premises for evaluating special characteristics of gold-bearing porphyry metal systems stem from their contrasts with properties of the class as a whole. Included features are differences in geologic, thus tectonic, environments, subtle but real differences in the proportions of accessory metals Mo-Ag-Au that are regionally and within some regions, tempo-rally distinct, contrasts in the Ag:Au ratios, petrological-geo-chemical as well as isotopic differences between intrusive suites, the age and nature of host terranes, contrasts in alter-ation style, and zoning variations of mineralogical and physical properties of rocks. These properties are linked in various ways in different regions and suggest that in large gold-bearing systems where gold may be uniformly distributed, environ-ments of emplacement, and compositions or sources of igneous "progenitors" may dominate in importance over processes, and that systems in which gold is zoned are processes-dominant.

Jan 1, 1990