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The Mobile Miner MM130 was delivered to Broken Hill in February 1992. During March the machine was extensively trialled on the surface to test manoeuvrability, climbing ability and muck handling prior to being trammed underground in April. The first cutting test on 30 April 1992 provided promising results. The machine has undergone continual development since it arrived in Broken Hill with aims of ensuring reliability and achieving performance goals. The paper gives a detailed account of recent performance comparing this with the predicted Performance.

Jan 1, 1993

By Fourney W. L, Dick R. D

A small-charge rapid excavation system employing a novel penetrating cone fracture initiation and propagation technique has been demonstrated to be capable of excavating the hardest of rocks at efficiencies (energy per unit volume of rock removed) four to ten times greater than attainable with conventional drill and blast. Significant enhancements to the concept developed during the research efforts include the use of propellant rather than explosive charges and a device for containing the charges and effectively sealing the shot-holes. The experimental results, including the excavation of several tons of hard rock in a research mine, have confirmed the novel breakage process and provided a data base for the design of a continuous hard rock mining machine based upon the concept. The small-charge excavation system would be attractive for civil construc-tion operations where sensitive structures, equipment and personnel would be in close proximity to the excavation face. The system would be attractive for selective mining operations where the ore rock could be fragment-ed and processed separately from the barren country rock. The barren rock could then be backfilled underground and eliminated from the traditional hauling and milling operations.

Jan 1, 1990

By Just J, Nguyen G, Dunn J. G, Graham J

A sample of pyritic gold concentrate was investigated by wet chemical and electron optical techniques. Sub-samples were roasted in a laboratory scale fluidized bed roaster in the temperature range 400-700¦C. The calcine was characterised, and cyanide-leached using a standard bottle rolling test. Gold extraction efficiencies varied with roasting temperature. At temperatures of 400 and 450¦C gold ex- tractions of less than 40% were achieved, but between 500-700¦C the extraction had increased to 93--98Z. The surface area of the calcine varied with roasting temperature, reaching a maximum at 500¦C. There was no correlation between the surface area of the calcine and the efficiency of gold extraction.

Jan 1, 1987

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

By Bensley C. N

In June 1995, BHP announced that it would build a Hot Briquetted Iron (HBI) plant and associated beneficiation, materials handling and infrastructure facilities at Port Hedland, Western Australia. This plant, the first direct reduction plant in Australia, will convert beneficiated iron ore fines into metallic iron for briquetting into HBI. The reduction plant will be based on the FINMET fluid bed technology jointly developed by Fior de Venezuela and Voest-Alpine Industrienlagenbau. Electric Arc Furnace steelmakers in the Asia Pacific region will be the principal customers for the product. This paper presents an overview of the facilities to be constructed by the project as well as discussing some particular technology and design engineering issues associated with the project.

Jan 1, 1996

Host minerals for gold have been of great interest to exploration geologists and metallurgists for a variety of reasons. The depletion of high grade ores in many parts of the world requires that greater attention be given to the study of host min-erals for gold. Some host minerals have been employed in exploration as traces for gold. They are also essential in the design of extraction processes for treating gold ores.This paper reviews the mineralogy of important gold deposits of Papua New Guinea (PNG), Indonesia and New Zealand and focuses attention on the ore minerals and rock-forming minerals that host gold.

Jan 1, 1994

By Sharma T

Laboratory investigations have been carried out on direct leaching of lead-zinc complex sulphide ore and zinc concentrate using ferric chloride. From the investigation it was observed that the use of 0.15 M and 2 M FeC13 gave an optimum dissolution of metal ions from ore and concentrate respectively. The kinetic studies conducted showed that the leaching reaction followed a shrinking core model for galena and sphalerite. The presence of impurities such as pyrite had increased the dissolution rate and reduced the consumption of ferric chloride. Further, the studies were conducted to recover dissolved zinc from the chloride solution by selectively precipitating it as zinc ammonium chloride.

Jan 1, 1992

By Kovscek P. D, Thimons E. D

The Bureau of Mines equipped a longwall shearer with a water- jet-assisted cutting system and measured dust levels during the cutting of a simulated coal block. The block was cut dry, at a conventional water spray pressure of 1 MPa and with water-jet-assisted cutting pressures ranging from 7 to 40 MPa. At water pressures of 20 MPa and higher, dust concentrations were reduced by as much as 85 % via water-jet-assisted cutting in comparison with conventional water sprays. This reduction was achieved without any increase in the water flow rate.

Jan 1, 1988

By Hatherly P, Luo X, Balusu R, Gale W

Ongoing, collaborative research between CSIRO's Exploration and Mining and Strata Control Technology has resulted in a better understanding of rock failure mechanisms around longwall extraction. Failure has occurred further ahead of the retreating face than predicted by conventional longwall geomechanics theory. In some cases significant failure has been detected several hundred metres ahead of the face position with demonstrated influences of minor geological discontinuities. Shear, rather than tensile failure has been the predominant failure mechanism in the environments monitored. Validating technologies of microseismic monitoring and new face monitoring techniques have assisted the development of predictive 2D computational modelling tools. The demonstrated 3D consequences of failure has assisted in the ongoing direction of the project to further investigate these effects.

Jan 1, 1998

By Boehme PW, Gregory OR

The results presented here show quite definitely that in the system investigated the intensity of dispersion is enhanced by switching the flow entry from bottom to sides of the packed trough. Since there is no reason to suppose that this would not be true generally then it is not surprising that the blast furnace dispersion data of Standish and Polthier lie above the data for packed columns with bottom fluid entry. In fact, on the basis of the present results, blast furnace dispersion results can never equal standard packed column behaviour but must always be above these. The result that the intensity of dispersion in the trough model is higher closer to the side ports than away from them is at variance with that of Standish and Polthier blast furnace results. Aside from the obvious structural differences between these two systems, it is thought that the presence of raceways and the tortuous path of the gas flow in the furnace may provide an answer. Clearly this is an important difference in the behaviour of the two systems and further investigations designed to clarify the position would have significant practical value. This would also give an indication of how the furnace D/ud values may be decreased along the whole height - assuming of course that this result gives the best overall performance of the furnace. However, there is to date no knowledge whatsoever about this aspect of blast furnace Technology.

Jan 1, 1975

By Meunier G, Davis J, Koperski G

The dry processing of mineral sands concentrates can result in the generation of significant amounts of airborne dust. The radioactive component of this dust has implications within the context of work environment health codes. The last four years have seen considerable investment in dry plant equipment enclosure and dust extraction systems, with resultant reductions in plant ambient dust levels. Simultaneously, an industry wide program was started to examine the origin, nature, mineralogy and radioactivity of the airborne dust. The major findings of this study have been: ò confirmation that monazite was the only significant source of dust radioactivity. ò recognition of two sources of dust: - agglomerates of finely divided ilmenite-rutile alteration products, which are formed by the removal of surface coatings and particles. - abraded mineral fragments, which reflect the mineralogy of the parent particles.

Jan 1, 1991

By M Coulthard, J Rivalland, K Dugan

Prior to 2001 Yallourn Mine has pumped approximately 1000 Megalitres of water per annum from aquifers beneath the mine floor in order to control aquifer pressures that were thought to have an influence on mine floor and permanent batter stability. In 2001 one of the deep aquifer pumps was shut down for five months in order to measure the aquifer recoveries. Prior to the shutdown a UDEC model was created in order to predict what level of recovery in the aquifer pressures would be critical to mine stability. The shutdown showed that the aquifer levels recovered and stabilised at levels that did not threaten the stability of the mine. The aquifers recovered to levels below the critical levels identified in the UDEC model.

Jan 1, 2003

By Ono K, Oishi T

Electrochemical determination of the oxy- gen partial pressure in the Fe-0-SiO 2 ternary systems saturated with solid silica was done by measuring the activity of oxygen in a silver bath in equilibrium with the molten slags using zirconia solid electrolyte galvanic cells. From the data obtained, the activity ~Faii.st composition relations were calculated

Jan 1, 1980

By Weining L

In-situ experiments were performed in a tunnel built in loess soil with the displace- ment components of the tunnel lining and the acceleration components of the tracks measured during the passing of trains. The measured parameters were then studied by the spectral method. As a result, the dynamic forces of trains was simulated numerically and a deter- ministic dynamic nonlinear analysis was carried out by means of finite element method. The results obtained by two different approaches were in fair coincidence. Results of the study indicate, that the low and medium frequency components of the dynamic train loading would be crucial for the dynamic responses of the tunnel lining and surrounding mass, and their effects would increase with the speed of passing trains within a certain range.

Jan 1, 1987

Edie Creek is located in the Morobe Goldfield about 17km by road from Wau in the Morobe Province of Papua New Guinea (PNG). Four distinct periods of mining development have occurred since discovery of rich alluvials in 1926. During the two years following discovery, individual expat-riate miners with gangs of native labourers mining rich alluvial gravels dominated the field. After the discov-ery of hardrock mineralisation in 1927, companies accumulated leases and devel-oped extensive underground mines and mechanical processing plants at Day Dawn Mine and Edie Creek/Karuka Mine between 1929 and 1942. After the Second World War, the underground operations were not re-opened, and mining activ-ities mostly concentrated on working alluvial and eluvial deposits. From 1962 onwards, Papua New Guinean miners became increasing producers as company activities declined. In 1990, Edie Creek Mining Company Pty Limited, a joint venture company involving Wau landowner groups commenced operations on New Guinea Goldfield's leases. It currently mines by open pit methods, rich quartz stringers and is invest-igating the open pitting of the Edie Creek/Karuka underground workings.This paper describes the mining and processing techniques employed during the various phases of develop-ment at Edie Creek in the past 70 years. The problems and hardships of operating on a new and remote goldfield are outlined.Abstract

Jan 1, 1994

By Christie AB

Stream sediment geochemical analyses from 140 mining company exploration surveys of the Coromandel, Northwest Nelson, Marlborough and Westland regions of New Zealand have been compiled from open file reports and entered on a database called REGCHEM (for Regional Exploration GeoCHEMistry). REGCHEM is supported by GEOEXPL, a custom-written computer software application which operates under the Microsoft Access relational database mangement system on a PC-type computer. The data are plotted as maps using the Maplnfo geographic information system (GIS) package. Thesholds separating anomolous values from background values are determined using the PROBPLOT univariant statistical package, which enables the descrimination and modelling of several populations. Relevant REGCHEM data are being incorporated into a GIS for the Coromandel region as part of ongoing studies to sevelop mineral deposit and metallogenic models for the region, and to assess regional prospectivity.]

Jan 1, 1995

By Bilodeau M. L

The paper describes a model which has been developed to assess the economic charac- teristics of base metal investment in Canada and the effects of past, present and possible future sharing systems, particularly mining taxation systems, thereon. The model is illustrated by applying the 1976 Canadian tax system to the economic characteristics of base metal discoveries made in Canada during the 1951-1974 period.

Jan 1, 1977

By T J. Scanlon

Heavy minerals recovered from recently discovered deposits in the Murray Basin are proving to be somewhat more difficult to process into saleable ilmenite products than ilmenites from existing operations. This is due to the nature of the gangue minerals present, the impurities in the valuable minerals and the size distribution of the mineral assemblages. Ilmenite product quality, in particular, can be adversely affected by any of these factors. Over the past two years the authors have been involved in assessing the potential to manufacture ilmenite products from a variety of mineral sand deposits in the Murray Basin. The steps undertaken to define the potential products and develop suitable flowsheets have evolved in parallel to the exploration efforts, in cooperation with companies undertaking exploration in the Murray Basin. A combination of an understanding of detailed mineralogy, application of magnetic fractionation and modification of magnetic susceptibility of the ilmenites has in all cases, been successful in improving ilmenite product quality. The targeting of particular ilmenites to specific downstream processes for TiO2 pigment manufacture is the most challenging aspect of this development.

Jan 1, 2001

A new least-squares method for inversion of d.c. resistivity soundings from horizontally layered earth is proposed. Powers are used as measured data. Apparent resistivity is generalized and apparent parameters curves are defined. Estimates for parameter errors are often possible even when data errors are unknown or large. Acceptance or rejection of a model is made an easier decision. Total computational effort is often reduced when compared to global least-squares methods, because although several optimizations are needed, few data points are involved in each, and initial guesses are requested only once and not all at the same time. Correlations between parameters may be used to improve solutions. Precise indications for extra needed data points can be conveyed. A test example is worked out and a field sounding, taken by Rijo (1973, personal communication) in an alluvium-filled river valley in north-eastern Brazil, is studied.

Jan 1, 1987

Gold Fields Ghana Ltd (GF Ghana) currently operates an underground mine at Tarkwa, in south--west Ghana. The mine was operated by Tarkwa Goldfields Limited, a wholly owned subsidiary of the State Gold Mining Corporation of Ghana (SGMC). The mine was making operating losses and in a poor state of repair. Tarkwa Goldfields retrenched all the staff and GF Ghana assumed management responsibility for its own account on I July 1993.

Jan 1, 1997