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The low grade Mount Charlotte orebody was first mined with minimum capital expenditure by mechanised cut and fill stoping. The lower block was prepared simultaneously for open stoping by shaft sinking and installing another crusher and services. Similar development for the third block was discouraged by economic factors and reduced tonnage. Decline develop- ment required less capital and opened up ore reserves commensurate with advance, providing flexibility to stop operations without commit- ment: A 1 in 7 decline measuring 4.25m x 5.5m to accommodate standard Euclid 25 tonne dump trucks was developed south of the orebody. A fleet of four trucks average 12 loads each per shift over a haul distance of 700m.

Jan 1, 1973

Carbonation of reinforced concrete is a potential durability issue for vehicular tunnels. This is particularly the case where elevated carbon dioxide concentrations exist and when the design life is 100 years or more. The process of carbonation can result in loss of passive protection to embedded steel reinforcement and initiation of corrosion. Therefore, tunnel design needs to consider the potential for carbonation on internal surfaces and how design life can be achieved in severe environments. This paper examines methods for predicting carbonation and how deterioration can be mitigated through appropriate concrete mix design and construction practices.

Jan 1, 2008

The port of Townsville is situated on the main north/south rail system of the Queens- land Government Railways and is the eastern terminus of the east/west rail link from Towns- ville to Mount Isa. With a stable beef and wool producing area along the east/west rail route, the expanding mineral industry development at its western end and the continuing growth of the Townsville region the administrators of the port are continually'keeping abreast and ahead of port development to ensure an effective and economic growth of port facilities to meet the needs of the area served by Townsville.

Jan 1, 1974

At 11 p.m. on Tuesday, 24th July 1979, an explosion of methane gas in a three heading development panel at Appin Colliery resulted in the deaths of fourteen men. The explosion followed after or was asso- ciated with a changeover of the ventilation to achieve a central intake between two returns. Investigation by Inspectors was followed by separate Judicial and Coronial Inquiries. Investigational information aimed at understanding the circumstances of the ex- plosion was prepared for the Inquiries. Recommendations following the Judicial Inquiry have been adopted by the Department of Mineral Resources.

Jan 1, 1981

Full aerodynamic design development of the proposed fans for the enlarged primary ventilation system at Mount Isa Mines Limited was initiated before tender specifications were prepared. Theoretical and analytical design studies were made of many possibilities to determine the optimum proposal. Major considerations were efficiency, simplicity, standardization, and mechanical feasibility. Model testing and experimental work covered blading design, inlet shape, diffuser and tail fairing dimensions, instrumentation requirements, ancl noise studies.Theoretical and predicted performance estimates were prepared for the three 20 ft diameter vertically mounted axial flow fans.

Jan 1, 1967

At Renison Limited, on the West Coast of Tasmania, modern trackless decline mining is practised to exploit the various tin bearing sulphide deposits. With footwall accesses, one of three adaptations of horizontal mechanised cut and fill, 1. unsupported, 2. pillar supported,and 3. unsupported - resuing is used to stope each defined ore block. The stoping method is basically determined by the dip and true thickness of the ore with emphasis on high ore recovery. Extreme flexibility is possible by the selective mining of stope lifts, the consumption of development waste as fill and the utilisation of the same mobile equipment in all phases of production. This has resulted in high productivity and low cost per tonne of ore.

Jan 1, 1977

The use of ammonium nitrate/fuel oil explosives is.now well established in most open cut mining operations. Its use. is extending to underground mining. This has been due in a large measure to improvements in the nature of the ammonium nitrate made available from various sources. The addition of surface active agents and water in controlled amounts to the fuel oil has been found to increase the sensitivity of the ANJFO mixture with consequent better explosive properties. It is considered that the surface active agent increases the bond between the ammonium nitrate and fuel oil giving a more, intimate physical and chemical mixing of the oxidising and reducing agent. This results in increased sensitivity and a faster rate of reaction. The increase in sensitivity has been accomplished without any diminution of safety. Tests which demonstrate the safety of this type of explosive are given in the appenuix.

Jan 1, 1964

A sample of tailings from a local, low grade (less than 2g/t) tailings dump was investigated for gold recovery. The tailings were very fine, with 90 per cent passing 30¦m and almost 60 per cent passing 10¦m. Tabling the coarse product from classification using a cyclone proved unsuccessful, with low recoveries being obtained due to high gold losses in the slime streams. Gold recovery by cyanide leaching was quite rapid, with recoveries of 85-90% being obtained in five hours. Lime and cyanide consumptions were 3 g/t and 0.1 kg/t respectively. Gold loading onto carbon was inhbited by the presence of the large amount of fines, so heap and vat leaching should be considered where the gold is recovered from a clear pregnant solution. Settling tests were conducted on tailings. It was observed that the addition of at least 3 kg/t lime or 0.4 kgh nonionic flocculant was necessary to promote settling of the tailings to generate a clear supernatant for gold and water recovery.

Jan 1, 1991

Instantaneous outbursts have occurred at Metropolitan Colliery from the pick and shovel work of early days to the modern mining techniques of today. Developments have been the introduction of an emission index to measure the proneness of the coal to outbursts, drainage and destressing by large diameter holes, attempts at higher productivity by the introduction of pulsed infusion shotfiring and improvements in ventilation. The future plans and aims for the Colliery include prediction of outbursts, seam gas pre- drainage and longwall mining.

Jan 1, 1980

A laboratory investigation was carried out to obtain data on the explosive character- istics of selected coals mined in New South Wales. Seven coal seams were sampled and the volatile matter content of the coals tested varied between 28 and 37 percent. A mod- ified Hartmann apparatus with a volume of 1250 ml was used in the investigation. Dust clou' generation was produced by an air blast delivered radially through a mushroom type valve and the ignition source was a-continuous A.C. spark produced by a 20 000 V, 50 mA transformer. The coal dust parameters invest- igated were the maximum pressure developed, the average and maximum rates of pressure rise at dust concentrations between 200 and 1500 3 g/m.

Jan 1, 1981

By Bhaskara Sarma P V R

Solvent extraction of cobalt from an ammoniacal ammonium sulphate medium was carried out using Di(2-Ethyl Hexyl) phosphoric acid in kerosene as diluent. The effect of ammonium chloride and ammonium sulphate on the extraction efficiency was studied. The extracted species in the ammonium chloride and sulphate systems were CoAz2HA.NH4CI and CoA3.HA.2(NH4)2SO4, respectively. Ammonia scrubbing and cobalt stripping studies were carried out from loaded and ammonia free organic Respectively.

Jan 1, 1992

By J E. Eberhardt

Ore sorting has long been used to raise the efficiency and thus lower the environmental impact of mineral processing operations. It was first instituted as hand sorting, according to a humanly perceived difference in the ore, but is now automated using large mechanical sorters in order to meet the high tonnage throughput required in most minerals processing applications. In the past, ore sorting was generally used as a niche processing route when other approaches failed, and in this context, consequential environmental benefits are often not the first consideration in adopting sorting. When applicable, ore sorting offers environmental benefits in reductions in fines waste, reagent usage and energy consumption in milling. Although there are significant opportunities for the use of ore sorting technology in many minerals processing operations, industry applications, to date, have been limited mainly to the processing of diamonds, magnesite, talc and uranium ores. This limitation has principally been due to a lack of suitable sensing technologies for a wide range of ore types. The authors report on a wide-ranging review of the automated sorting of mineral ores, and in particular, on methods for discrimination of ore characteristics prior to mechanical sorting.

Jan 1, 2002

The word governing derives from gubernare meaningto pilot a ship. Being inclined to metaphors, one could be forgiven to think that politicians act this verb and captain the Nation's ship into some definite course. In the case of at least the mineral resources industry, it seems that there are not many James Cook followers in our parliaments: Australia's approach to mineral and energy policy is often chaotic - witness the 1935 to 1961 ban on iron ore export-ing which prevented the development of a significant steel industry at time when the World was hungry for this metal, just to mention one amongst many other examples.The follies of Australia's mineral policies are well il-lustrated in the case of uranium mining. Although Australia had the Western World's largest economic reserves of uranium, it is onlythefifth producing nation and its uranium potential is largely unrealised. At the root of this situation are the interventionist attitudes and policies of successive Federal Governments which for more than four decades distorted the Investment decision and, in more recent times. discouraaed investment.

Jan 1, 1990

By S F. Simmons, A McOnie, J L. Mauk

Three cross sections, 200 m apart, display the distribution of indicator hydrothermal minerals across the Empire zone of the Golden Cross epithermal Au-Ag deposit, Waihi, New Zealand. These minerals are used to interpret the temperature and composition of hydrothermal fluids. The distribution of interstratified illite-montmorillonite and illite indicate that temperatures ranged from 140 to >220¦C, with temperatures above 220¦C predominating. The mineral assemblage of quartz-adularia-chlorite-illite-calcite-pyrite envelops the Empire vein system and stockwork, and reflects formation from an alkali chloride water whereas the mineral assemblage of replacement calcite-interstratified illite û montmorillonite-kaolinite forms a carapace and reflects formation from a CO2-rich steam-heated water. Alkali chloride waters appear responsible for the epithermal Au-Ag mineralisation.

Jan 1, 1995

By Armstrong G. J, Bowling K. McG, Gray C. H

An experimental induration facility has been developed and used for conducting iso- thermal tests and plant simulation studies on the thermal induration of iron ore pellets. The influence of time, temperature, lime content, ore type, shale content and particle-size dis- tribution (e.g. Blaine Index) is being studied in a continuing programme. The present paper deals with experiments relating to the first three of these parameters and illustrates the use of an experimental design suitable for statistical analysis. The relations between isothermal data and the results of complete simulation rests are discussed.

Jan 1, 1973

By Grinenko VA

Mineralogical, chemical, and isotopic data have been obtained for samples from 11 volcanoes and 4 kortlandite intrusives on Kamchatka.Similarities and differences in ore-bearing and barren intrusives are discussed. Differences in sulphide mineralization and sulphur isotope compositions of intrusives are explained in terms of the "auto-sulphurization" hypothesis which involves the redox conditions of the host rocks. possible role for carbon in nickle sulphide ore formation is also considered.

Jan 1, 1990

By Jones IO, Coles A, Austin D

This research project came about as a result of ICI Australia offering a scholarship to a final-year mining engineering student at the Western Australian School of Mines. A signifi-cant part of this year of study is devoted to an industrial project and consequently one of the conditions of the award is that the successful applicant pursue a research project of interest to the donor company.Having selected the project and the most appropriate final year student, a steering committee composed of representatives of ICI Australia, Kalgoorlie Mining Associates, the Mines Department and the WA School of Mines was set up. This committee is largely responsible for planning the main thrust of the research work whilst the detailed planning and day-to-day activities have been largely the responsi-bility of the research student, his academic supervisor and senior staff at the Mt Charlotte Mine.

Jan 1, 1984

By Hayes P. C

The kinetics of reduction of PbO-silicate melts in CO-N gas mixtures at 900¦C have been studied. Rea~tion rates were measured by moni- toring the CO2 content of the product gas. A wide range of gas and melt compositions and gas flowrates have been investigated. The overall reaction rates in heterogen- eous systems are typically characterised by a steady increase as the gas flowrate is in- creased. At low flowrates the processes are limited by gas film mass transfer. At high flowrates it is expected that the rates will tend to maximum values determined by either the rate limiting chemical reaction or diffusion in the condensed phase. In the present series of experiments it has been found that for any given gas composition the overall reduction rate goes through a maximum with increasing gas flow. The maxima, which occur at relatively low gas flows, are more than an order of magni- tude greater than those observed at high gas flowrates. The results of these and other experiments are presented and analysed. Possible rate limiting mechanisms in the reaction system and their implications regarding commercial reactors are discussed.

Jan 1, 1987

Historically BHP Billiton Alliance Coal Operations Pty Ltd (BMA) have generated resource models from widely spaced data points (drill holes). The accuracy of these models has been influenced by the degree of local structural disturbance of the coal seams and by the choice of interpolators used in the modelling process. In some circumstances unacceptable vertical errors of up to 10 m have been observed whilst mining. New terrestrial photogrammetry or laser imaging technology now allow the 150 or so kilometres of exposed highwalls in BMA to be rapidly, accurately and safely mapped and the three-dimensional images economically incorporated into resource models, reconciliation grade control models, drill and blast designs and for pit stability analysis.

Jan 1, 2005

The mining and resources industry in general has relied on macro separation technologies (greater than 1 micron) through processes which include: ò sedimentation ò flocculation and coagulation screening and filtration ò absorption ò magnetic separation ò chemical leaching and precipitation Essentially, these processes and technologies provide the industry with an effective arsenal to handle most separation requirements to date. Dewatering of solutions is one of the most significant requirements of the resources industry, as practically all mining endeavours use water in their process for leaching, extraction, cooling, dilution or for potable drinking water.

Jan 1, 1989