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The story of the Penjom gold mine located near Kuala Lipis on the Malay Peninsular demonstrates the valuable role successful exploration companies can play in the development of the gold mining industry. Avocet Mining PLC ('Avocet') began exploration in the area on a limited budget in 1989, securing land tenure around the Penjom alluvial workings in July 1990. The lease granted, known as Block 7, formed part of a land package offered at the time by the Pahang State Government to develop the resources of the area. Until the late-1980s, the Kuala Lipis region, situated approximately 180 km north west of Kuala Lumpur, had restricted accessibility for security reasons precluding serious exploration or mining activity. The situation has changed dramatically in the 1990s, with several foreign explorers active in the Peninsular, targeting old alluvial and underground workings adjacent to the north-south trending Raub-Bentong Suture. Deeper drilling of these prospects has shown there is potential for both small- to medium-scale open pit mining and possibly underground operations, providing companies such as Avocet with an ideal mining investment opportunity.

Jan 1, 1997

By Durucan S

The southern Attiki peninsula is a very interesting area from an environmental point of view. The port and the city of Lavrio is situated at the east coast of the peninsula with about 10 000 inhabitants and there are also a few villages in the vicinity. The south-eastern part of the peninsula hosts the famous Lavrio mines which exploited the silver bearing orebodies of the area for more than 25 centuries. As a result, soils around the city of Lavrio are polluted with high heavy metal loads. The area is also of archaeological interest, as there are well preserved remnants of ancient mining and processing plants and archaeological sites. Soil samples collected from an area of approximately 120 km2 around Lavrio were analysed for their metal contents and the spatial distribution of the concentrations of ten selected elements were estimated from these data sets. The spatial data analysis and transformation capabilities of Geographic Information Systems, combined with extensive mining and geological data, helped the authors to identify the extent and causes of metal pollution around Lavrio.

Jan 1, 1995

The Hemersley Ranges are located in the North West Division of Western Australia and extend, approximately, from latitudes 21¦ 30! to 23¦S and longitudes 117¦ to 120¦E. Their mean height above sea level is'. 2,000 feet, and they rise from 600 to 800 feet. above the gen- eral level of the tableland which extends south-east from the coastal town of Roebourne.. Mt. Bruce, the highest peak, is 4,024 feet above sea level. The ranges are intersected by numerous north-flowing streams, dry during the greater part of the year, which have carved deep gorges, and it is in these that the principal deposits of orocidolite outcrop. The presence -of the mineral was first recorded in 1917., but the deposits remained untouched until 1937 when reports of a strong market demand for-croeido lice resulted in considerable prospecting and mining activity, particularly in Yampire, Wittenoom and Daleis Gorges. . It was established also that the blue asbestos belt extended from Willi- Wolli Springs north-west to Millstream Station, i.e.,-over a.:length of 180 miles and a width of 20 to 30 miles. A number of attempts were made to develop aid treat the Yampire and Wittenoom'Gorge deposits from 1938 onwards, but, for a ,variety of reasons, none of these-proved successful. Current production,. is wholly by Australian Blue Asbestos Pty. Limited at Wittenoom Gorge. This company commenced operations at the Wittenoom Mine in 1946, with an output of 601.8 long tons of- fibre,. and later transferred tb the Colonial Mine about one mile to the north-west. Output has been increased steadily to an' average of 12,000 to 14.,000.. long tons; per annum over the past six years. The total Western Australian output to the end of 1962 is reported by the Mines Department as 110,013 long tons valued at úAl2,403,728..

Jan 1, 1964

By Morrison K

This paper describes an approach developed by the authors for integrating social and environmental impact assessment (SIA and EIA) for mining projects. The approach is an evolving one and is based on experience gained over the past five years undertaking environmental and social impact assessment for a range of mining and other projects. The approach described is an attempt to systematise the various steps undertaken in impact assessment and the means of integration of the two approaches.

Jan 1, 1987

The coking coal produced by Utah Development Company in the Bowen Basin is processed by a dual system of dense media cyclones for the 30mm x 0.5mm feed and flotation for 0.5 x 0mm material. The basic metallurgy of these processes will be presented with emphasis on the operational characteristics which are peculiar to coal. Potential areas for process improvement by the application of more sophisticated control systems will also be discussed.

Jan 1, 1978

By Ritchie I, Fleay J

The key issues in the conceptualisation and testing of treatment options for gold and base metals mineral processing projects are discussed. A prerequisite of this process is the need for close interaction between geologists, mining engineers and metallurgists to facilitate an understanding of the orebody based on the parameters impacting on each discipline. Typical testwork programs for unit operations, including comminution, flotation and gold processing are Described.

Jan 1, 1997

A novel solvent extraction process, called the SOHNEX process, has been developed at the University of Utah. In this process, the organic and the aqueous phases flow countercurrently in a horizontal vessel, and the emulsion between the two liquid phases is generated by high-velocity gas jets injected at the bottom. The gas jets are located at certain intervals along the bottom of the vessel with phase disengagement zones on either side of the plume zone created by the gas jet. The system is simple, having no mechanical moving parts or complex internal structures, and yet provides good contact between the phases with minimal backmixing. Tests have shown that emulsions with a wide range of specific interfacial area, including that typically encountered in mixer-settlers, can be generated in this process. It has significant built-in flexibility of operation including the control of the flowrate and hold-up of each liquid phase. The SOHNEX process overcomes the difficulties in the operation of conventional solvent extraction equipment such as mixer-settlers and column extractors. A major advantage of the SOHNEX process is that the energy of mixing can be closely controlled by adjusting the strength of the gas jet. This allows an optimal control of the drop-size distribution of the dispersed phase and thus the specific interfacial area. The process is continuous, and any number of extraction and separation stages may be built into a single vessel. The gas can be recirculated in a closed loop, thus eliminating solvent loss and mist problems, especially for high-temperature operations. The SOHNEX problem can handle solutions that contain suspended solids and that form third phases. The simplicity of the equipment and operation with low maintenance will mean much reduced capital and operating costs as well as low environmental risks and improved safety. The SOHNEX process has been tested for continuous copper extraction from a dilute solution. Calculations also showed that uranium and other radioactive elements can readily be extracted in a small unit of the SOHNEX extractor while satisfying the nuclear criticality condition.

Jan 1, 2000

May I first of all say that I am fully conscious of the great compliment paid to me when I was invited to accept the Presidential Chair for this current year. I realise that it is an onerous task by reason of the fact that the Chair has been occupied in the past by so many able and distinguished men, and I realise also that I have been set a standard which is hard to emulate. "It is my desire however, in accepting the post that I may be able to contribute in some small measure to the further advancement Of the aims and objectives of the Institute and I thank you all for the confidence you have shown in me.Secondly, on behalf of the Company and in my Presidential capacity, I want to extend to each and everyone of you a hearty welcome to Whyalla and I hope that you will all return to your respective fields of endeavour feeling that you have had a most interesting, enjoyabIe and instructive time with us here in Whyalla.In this year of 1951 marking as it does the culmination of the first 50 years of Federation in Australia and yet another half century of human endeavour and progress, we are brought to a point where it is perhaps natural that we should pause, to review what has been achieved, in that span of time, and to look at the tasks ahead.It is no exaggeration to say that the story of Australian development since the inauguration of the Commonwealth 50 years ago has no more remarkable chapter than that of the-growth of its manufacturing industries.Each decade has borne witness to steady and substantial growth of our secondary industries and whilst it is true that our financial well-being still rests heavily on our primary production, we have, as a nation, moved surely in the direction of a more balanced economy. More and...

Jan 1, 1951

By M Kilburn, A Edenton, M Adam, A Dehghan-Manshadi, R Smyth, L Lu

The blast furnace is a counter current reactor. The counter current principle of the furnace makes it very efficient in transferring the heat and mass required to drive the reduction reactions inside the furnace. However, this does impose a stringent requirement on the permeability of burden material in the furnace. Lump ore is one of the key ferrous feeds used in the blast furnace ironmaking process, often accounting for ten to 20 per cent of the blast furnace ferrous burden. As the lump ore descends through the blast furnace, it is dried, heated and reduced by the ascending hot reducing gas. To ensure good furnace permeability, generation of fines from burden materials including lump ore due to mechanical, thermal and chemical processes needs to be minimised. Unlike sinter and pellets, lump ore is subject to thermal degradation. To assess this behaviour of lump, the ISO decrepitation test (ISO 8371, 2007) is often conducted, and the result is calculated as a decrepitation index (DI). However, the DI values obtained from the existing ISO decrepitation test vary considerably between test portions and between laboratories, which makes meaningful comparison very difficult. In order to identify the sources responsible for the unacceptable repeatability, the effect of various testing conditions, such as particle size, heating rate, sample preparation and loading method, on the mean DI value was studied. The mechanisms contributing to thermal degradation in the top of the blast furnace and during the standardised decrepitation test are also discussed.CITATION:Lu, L, Kilburn, M, Dehghan-Manshadi, A, Adam, M, Edenton, A and Smyth, R, 2013. Thermal degradation of lump ore in the top shaft of blast furnaces, in Proceedings Iron Ore 2013 , pp 421-426 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

As this paper is being written primarily for perusal by milling workers, metallurgists and engineers, an attempt will be made to avoid the use of accounting technicalities. Its scope will be confined to a description of the methods employed in the collection of basic information for use in timekeeping, costing, and the compilation of statistics.TIMEKEEPINGEvery applicant for work is asked to furnish the following information, which is collected on a card (size 6 in. x 4 in.)...

Jan 1, 1922

The exploration and mining risks are investigated and compared to the risks of smelting, secondary processing and other normal industrial activities. This study concentrates on the risk before, or at the investment decision. Internal and external risks are distinguished. Internal risks are the risks inherent in every engineering design and common to all projects. The main external risks are the financial risk, changes in prices, location problems and geological factors. Financial risks concern every capital-intensive and export-oriented project and cannot be considered as typical mining risks. Changes in prices, i.e. the market risk, concern every industry using raw materials, but the market risk is especially accentuated in the mining industry. Problems of location and infrastructure are normally more significant in mining than in other projects, and geological risks are unique to mining. All these risks associated with mining projects combine to form a risk at least twice as high as that for other normal industrial activities. Within the range of profitability of mines, which on average is the same as in the manufacturing industry, only a few highly profitable mines exist. These few mines are the sole reward for the high risks taken.

Jan 1, 1986

By Singh T, Singh D. P

India has limited resources of coking coal. Most of the coking coal seams are located in Jharia Coalfield. These seams were worked in the past by the bord and pillar system in a haphazard manner, which has resulted in honeycombs of old working. Most of such areas are under fire. In order to meet the demand of coking coal in the 21st century, it is essential that the coal locked due to old underground workings is recovered fully by conducting opencast mining to an ultimate depth of 500 m. The major problem envisaged in conducting opencast mining in such areas will be the stability of pit slopes over voids and the behaviour of subsided material in the pit slopes. An attempt has been made to simulate this complex situation from a specific section of the rockmass of a mine in an equivalent material (EM) model. The old workings existing in upper coal seam (V) were simulated by developing staggered bord and pillar workings in two sections and depillaring them. Opencast mining was conducted for recovery of coal locked due to irregular working in coal seam V. The slope instability caused by intersection of the slope with the void, during frontal working (by shovel-dumper combination) was observed in various situations. In this paper, the technique adopted for simulation of a 125 m thick section of rockmass in an EM model is outlined. Adverse effects of staggered workings and

Jan 1, 1988

In many metal mines in China,the 70B2 series of fans has been used for main fans for a long time.These fans generate higher static pressures than are required for the relatively high equivalent orifices of the ventilation systems of many of the mines. As a consequence, their running efficiency is common only around 30%. The loss of power is significant.

Jan 1, 1988

By Shining Z

The properties of coal or rock containing gas are very important both for studying coal and methane outburst mechanism and for controlling underground rock in mining. The rheological fracture properties of coal containing gas were studied to obtain its rheological fracture principle both in microscopic scale and in macroscopic scale. The application of this principle is successful in explaining coal and methane outburst mechanism and for putting forward a rheological hypothesis of coal and methane outburst.

Jan 1, 1992

By I Testrow, M Wiggin

Scrutiny of the whole explosives industry has increased as a result of the terrorist attacks on the World Trade Centre and the Pentagon on 11 September 2001 and the bombings in Indonesia, including the Bali bombings last year. This has been highlighted in specific press releases from governing bodies, like the Department of Mineral and Petroleum Resources û Western Australia, on the necessity of being in compliance with regulations for storage of explosives. As a result, audits by inspectors to assess compliance are to be expected. In a proactive move, DynoConsult has assisted several customers through benchmarking current practices, in order to identify any areas of non-compliance to the statutory requirements for explosive storage and security. This paper discusses the outcomes of supplier discussions and customer audits and highlights the implications for the industry.

Jan 1, 2003

The Warner Process has been devised to produce zinc metal directly from sulphide, thereby reducing the requirements for purchase of large amounts of energy in a special form. The process conditions for a practical process have been evaluated in an extensive program of research and development at the University of Birmingham. Recorded data now exists to take the process forward to commercial use within the next five years. The industrial economics have been evaluated. The cost of making zinc metal from zinc sulphide ore can be substantially lowered due to the reduced energy cost, locating zinc production in the neighbourhood of the mines and increasing ore to metal recoveries - particularly for fine-grained and pyritic ore. Integration of a Warner Furnace with a zinc mine and concentrator can result in a highly attractive return on capital Invested.

Jan 1, 1993

By Restarick CJ

A compound cylinder-cyclone system, fitted with a flow control valve between the cylinder and cyclone, has been used for coal slurry sizing experiments in the range approximately 100 to 300 micrometres. An important feature of the system is the ability to adjust the cut size of the separation over wide limits by adjustment of the flow control valve. Results have been compared with typical fine screening operations. Under roughly equivalent conditions the compound cyclone system can achieve better elimination of extreme fines, but is not as sharp as the screen for coarser size cut-off. Simulations of systems involving combinations of the cylinder-cyclone system with screens indicate that the advantages of both sizing devices can be combined to yield accurately sized products for fine coal cleaning, at much less cost than using screens alone.

Jan 1, 1984

Krupp Polysius AG, FRG, in close cooperation with Prof. Dr. K. Schoenert, FRG have developed the principle of the high pressure grind- ing roll POLYCOM. The POLYCOM mill basically consists of two counter-rotating rolls of large diameter and relatively small width, one of which is fixed and the other moving in slide blocks. The pressure required for comminu- tion is applied via the sliding roll by a powerful hydraulic system. The comminution takes place between the rolls under high pressure in the bed of material by nipping and compacting. The top feed size-depending on the rolls diameter -may be as coarse as conventional secondary crusher feed and the product is a compacted cake containing a high amount of fines created by micro-cracking. The amount of fines depends on the pres- sure (grinding force) applied. Operating results show that even in wet griding circuits capacity increases at downstream connected grinding mills of up to 100010 can be accomplished with an interconnected POLYCOM machine and energy savings of up to 25070 may be achieved depending on application. POLYCOM can be used in existing grinding plants for low-cost upgrad- ing of capacities but also as an advanced alternative to conventional crush- ing and grinding equipment in open or closed circuit configuration. A single industrial size 2.8m roll diameter POLYCOM machine may be fed with top feed size of up to 200mm and produce a finish product as fine- grained as known from rod and ball mills but with less energy consumption. Meanwhile, the POLYCOM high pressure grinding roll has established itself world-wide in the cement industry and is now entering the mining industry. POLYCOM machines are currently designed in industrial standard sizes of 1.0m to 2.0m rolls diameter and drive units of up to 2400 kW. This paper includes: principles of high pressure grinding, main fea tures of the POLYCOM machine, results of tests on various materials including Australian gold and copper ores carried out at the POLYSIUS research centre in Germany. Some examples of industrial applications of high pressure grinding will also be presented.

Jan 1, 1988

By Masters I. M, Ozberk E, Chalkley M. E

The integration of iron rejection as hematite with the Sherritt two-stage zinc pressure leach process has been investigated on the laboratory scale. The two-stage pressure leach process is applicable for a greenfield zinc plant, or for replacement of the conventional roast-leach circuit in an existing zinc plant. An excess of zinc concentrate is used to accomplish acid neutralisation in the first stage of pressure leaching, and the residual concentrate in the first stage residue is treated with an excess of acid solution in the second stage of pressure leaching to yield high zinc extraction. Integration of hematite precipitation with this process allows for the potential sale of the iron residue, greatly decreasing the residue disposal problem. Two flowsheets containing the desirable features of both of these processes are described in this paper, along with laboratory Results.

Jan 1, 1993

By Just G. D

The results of a geostatistical analysis of geochemical data obtained from field measurements are described in the paper. Q values derived from seismic signal rise times for different travel paths in the rock masses were used in the study. Cross-hole seismic measurements made at surface and underground sites formed the basis for the work. Geostatistical estimation of average l/Q values for area of the rock were compared with geological interpretions of rock type distributions. Reasonable correlations were obtained between the two methods of rock quality estimation.

Jan 1, 1988