Search Documents

The successful operation of diesel equipment underground does not entirely depend on selection of robust, reliable, easily maintained machines. Results are also heavily influenced by the following factors: Design and condition of the operating area. Skill of operators. Correct maintenance facilities. Experience, skill and initiative of maintenance personnel. If the mine layout does not allow access to a central workshop area, the effect of any shortcomings will be magnified. The best results will only be obtained by close co-operation between mining and maintenance departments right from the initial planning stages.

Jan 1, 1977

By Price B. D, Staunton W. P

The Mineral Science Laboratory of the Government Chemical Laboratories has recently investigated various procedures for the analysis of the platinum group metals (PGMs). This investigation covered a number of methods for the extraction and preconcentration'of the PGMs from a wide range of geological materials. The nickel sulphide extraction technique proved to be overall the most applicable procedure. Flame atomic absorption spectroscopy (FAAS), electrothermal atomisation atomic absorption spectroscopy (ETA-AAS), inductively coupled plasma atomic emission spectroscopy (ICP-AES) and inductively coupled plasma mass spectrometry (ICP-MS) were examined for their suitability in analysing platinum group metals in solution. ETA-AAS and ICP-MS proved to be the instruments of choice due to their low detection limits.

Jan 1, 1987

By Adamiak Z. P

A study has been made of the influence of bentonite type on the wet strengths, dry strengths and drying rates of pressed iron ore pellets. Measurements of the influence of bentonite on the kinetics of growth of pellets are also reported. The results show that bentonite decreases the rate of growth of pellets and the drying rates of pellets while increases are observed in both wet and dry strengths. The results have been interpreted in terms of the physical and chemical charact- istics of the bentonite and the suitability of a given bentonite for particular pelletising operations has been discussed.

Jan 1, 1973

Using a new type of laser surveying instrument named Particle Dynamics Analyser (PDA), the distributions of the radial and axial components of the mean velocity, the size and the concentration of solid particles at selected positions within a transparent hydrocyclone were directly measured out for the first time, from which profiles of the flow field of solid particles were obtained. And some new points were put forward such as the locus of zero vertical velocity (LZVV) of solid particles was not the same as that of liquid, and some particles in inner helical flow could also be separated. The results are of great significance to farther ascertain the separation principle of hydrocyclones and improve the separation efficiency.

Jan 1, 1993

By C. P. BATES

In November 1969, New Zealand Steel Ltd pioneered the commercial use of the SL/RN solid fuel direct reduction process to make sponge iron as a feed material for electric arc furnaces. Serious process problems with the use of green balls and coal injection were progressively overcome. The process was developed by New Zealand Steel along a radical route, of feeding the fine grained raw ironsand concentrate and coal directly to the kiln. Contemporaneously with this development of direct reduction, steelmaking process innovations were made that enabled the arc furnaces to operate successfully with the high volumes of acid slag.

Jan 1, 1980

This paper provides an insight into the current status of risk management practices within our industry, based on an industry wide survey, with deliberate cross-reference to quantitative analysis. This survey showed that quantitative assessments appear to be mainly hampered only by the lack of reliable data and industry expertise to carry out such assessments. A short case study will illustrate some of the necessary basic tools and data types that would enable the industry to tap into an additional range of business improvement dimensions to more effectively manage the diverse and changing risk profile of the mining sector.

Jan 1, 2003

Independent assessments of existing and projected mining operations are often required in the exchange of assets and for raising capital, requirements which are particularly prevalent where there are new mining fields, a characteristic of the Pacific Rim area. Such audits and appraisals typically consist of a geological evaluation of the ore deposits; estimates of mineral inventories and mineable reserves; assessment of mine plans and costs; assessment of ore processing methods, recoveries, and costs; assessment of infrastructure and G&A (general and administrative) requirements and costs; assessment of environmental, permitting and reclamation requirements and costs; and, finally, economic evaluation based on various discount rates and metal prices. Audits provide a challenging task for consulting engineering companies, but one well worth the effort for mine developers and those connected with financing of the mining industry.

Jan 1, 1990

A new two-metre column self-heating test procedure has been developed at the University of Queensland, which clearly shows the hot spot development phases that take place in bulk coal self-heating. The column results provide a more reliable indication of the self-heating propensity of coal than small-scale index tests. At the same time, off-gas evolution patterns associated with hot spot development are obtained, including the recognition of hydrogen evolution from oxidation at temperatures less than 80¦C. Subtle differences in off-gas evolution from self-heating between gassy and gas-drained coal are also apparent. This new approach to coal self-heating assessment offers an opportunity to further the understanding of the complexities of spontaneous combustion and will enable more accurate risk assessment for the coal industry.

Jan 1, 2005

By R H. Boffey

The Osborne copper-gold deposit was discovered in North-West Queensland in 1989. Underground production activities commenced at Osborne deposit in April 1996. This paper will examine technical and operational aspects of the underground mine during its development to a 1.2 Mtpa operation . Technical aspects discussed include geology, mine design and mining methods, equipment fleet selection and capital infrastructure. Operational aspects discussed include the evolution and performance of the integrated work teams that are utilised at Osborne to perform all mining and maintenance activities.

Jan 1, 1998

The Victorian State Government recognises that the extensive brown coal deposits in Victoria are one of the State's key competitive strengths for economic development. The unique properties of the coal, together with the ease of open cut mining, make it suitable for a variety of new applications. Research and development activities are centred around applications which take advantage of the natural attributes and unique properties of the coal. The high reactivity and low ash content of the coal led to its selection for the Japanese brown coal liquefaction pilot plant currently operating in the Latrobe Valley, with support from the Victorian Government and the Coal Corporation of Victoria. Research and development of new brown coal based products together with many other areas of applied and fundamental research are being conducted in Victoria by Government research organisations, tertiary insti- tutions and private industry, with the objective of establishing new indus- trial developments based on Victoria's vast brown coal resource.

Jan 1, 1989

By M Gao, V Lawson, W Valery

Changes in metal prices and mine output over recent years have required the Copper Concentrator of Mount Isa Mines to operate at annual tonnage rates varying from 4.0 million to 6.5 million tonnes. Several circuit combinations were operated during this period utilising up to two semi-autogenous grinding (SAG) mills and up to two ball mills. The aim was to maximise grinding efficiency and keep unit costs constant regardless of throughput rate. Measures to improve the SAG-ball mill unit operation were implemented with each circuit change. These included installation of a splitter to divert SAG Mill cyclone underflow back to the mill, increase SAG ball charge from four per cent v/v to eight per cent v/v, reduce in SAG top feed size and increase of ball mill grinding medium size. Modelling work and surveys led to a new design of the SAG liner profile from 60 rows of rail bar liners in a high-low arrangement to 40 rows of top hat liners in a high-high arrangement. An on-line SAG Mill feed sizing monitor was recently installed to improve grinding control.

Jan 1, 2000

HISTORY OF PROCESS DEVELOPMENT The manufacture of coke from coal commenced at the beginning of the 17th century by heaping coal into circular mounds in the open, covering with earth, clay or ash and slowly burning the coal in the mounds to produce a heap of coke. Naturally the process was slow in production rate with low coke recovery due to the loss of that part of the coal which was completely burnt to ash. As a natural consequence of this initial carbonisation method, a coke oven design was developed so that the coking chamber, which was constructed of brick, was circular in plan, cylindrical in section with a dome shaped roof - similar in shape to the original coal mounds. As the shape of the chamber was similar to the old dome shaped beehive, the ovens were called beehive ovens. The ovens were built in long single or double rows with retaining walls between each oven and as such were known as a battery of beehive coke ovens. In these early beehive ovens, coal was charged from hand wheeled tubs into a hole into the top of each oven, hand- levelled with a rake and the oven side opening sealed with bricks and clay except for some small holes in the opening to admit limited quantity of air for combustion. Coking commenced by the heat retained in the brickwork from the previous charge. The gases evolved from the coal, together with the admitted air, were partially burnt inside the oven to supply the heat for carbonisation and the surplus gases were burnt to waste at the top charging hole. The heat from this gaseous combustion inside the oven together with the reflected heat from the brickwork of the arched roof of the oven allowed carbonisation of the coal charge to proceed from its surface slowly downwards to the floor of the oven. At the end of the coking cycle (usually 4 or 5 days) when there was no more evolution of gases, as indicated by diminishing gas flame and a drop in oven temperature, the brickwork of the oven opening was removed. The coke was then quenched by inserting a pipe with spray holes to spray water over the coke charge in the oven after which the coke was raked from the oven. The work of charging and levelling the coal, bricking and removal of oven opening, quenching and raking out the coke all required manual labour. As these ovens only carbonised a 5 to 7 ton charge of coal per cycle of 4 to 5 days, to produce 3 to 41/2 ton of marketable coke, the labour required per ton of coke was high.

Jan 1, 1975

It is extraordinary that while Australia depends heavily on mineral wealth for its economic well-being, most Australians have no appreciation of the traditions and principles which drive and govern the mineral industry. Their understanding has been largely provided by those who campaign against the industry in one way or another and is therefore quite unrepresentative.

Jan 1, 1993

Activated carbon is ideally suited to treating low grade ores and tailings by the carbon-in-pulp process and is rapidly replacing the use of zinc for recovering gold from cyanide leach solutions. Coarse carbon particles derived from coconut shell adsorb up to 30,000 ppm Au as a gold cyanide complex and can leave barren solutions containing

Jan 1, 1982

Optimisation of an open-pittable orebody raises many questions relating to the operation, corporate objectives and orebody characteristics. Often the `black box' is expected to provide instant answers to many complex questions. The aim of this paper is to pose some commonly asked questions that arise during an optimisation study, and to try to provide some answers. The questions are aimed at typical objectives that affect the project and are of primary concern with the decisions that affect its course during the various development stages.

Jan 1, 1997

By Gurgenci H, Slifirski M

The Centre for Mining Technology and Equipment was established in 1991 to develop innovative technologies for the mining and processing industries, to introduce these technologies to the industry, and where appropriate, to co-operate with equipment manufacturers to transform these technologies into equipment products. It is an unincorporated joint venture between the University of Queensland, CSIRO and the Australian Minerals Industries Research Association. Base funding for the CMTE is provided by the Federal Government as a Co-operative Research Centre.

Jan 1, 1993

By E P. Nelson, R Gutierrez, P W. Layer

The San JosT district in Patagonia comprises a number of epithermal precious metal quartz veins hosted by a Mesozoic volcanic sequence. New radiometric data indicates that upper Jurassic volcanism was closely followed by vein mineralisation in the lower Cretaceous. A structural model is discussed for the district at times of mineralization that may also apply on a regional scale and other mineralised districts in Patagonia. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

The smaller mining company with full ownership of, or participation in, a mining project is generally unable to obtain funding as easily as the major mining house. While the equity market remains the main funding source for small projects, debt fund- ing options are becoming more available. Many international banks possess in-house mine fin- ancing expertise which can assist the smaller company in financing its share of project development. A clear understanding is necessary of both the benefits and limitations of bank funding, to ensure that all potential sources of funds are properly considered and integ- rated into the financial plans of the smaller mining companies.

Jan 1, 1984

BlIP Minerals is a large, diversified, international mineral producer. This paper describes the company's operating strategy, and identifies the role of mineral processing in this strategy through three examples: the column flotation installation at Escondida in Chile, the leach-SX-electrowinning plant, proposed for Escondida, and the whole-ore roasting process being constructed for the Syama gold operation in Mali. It is concluded that the application of appropriate and sometimes novel mineral processing technologies can achieve significant benefits in reduced operating cost, improved product quality, and in some cases the exploitation of previously uneconomic deposits, thereby providing strategic advantages to the company.

Jan 1, 1993

By T C. Hughes, R Hughes

Ausmelt has developed and commercialised high temperature reactor technology that has been applied to waste processing in the form of a catalytic waste converter (CWC). Ausmelt Technology uses a top submerged lance system within a versatile converter containing an oxidised molten siliceous slag. Metals and other valuable products can be extracted from wastes for recycle into the community. Non-valuable components such as toxic organochlorinated compounds are destroyed and prevented from reforming. The slag produced is inert and can be safely used in building and concreting. The CWC can be applied to practically all types of wastes and examples from Ni-Cd batteries to toxic wastes are discussed. Additional benefits can be derived from large-scale operations if the surplus heat generated is exploited to produce steam and electricity.

Jan 1, 2000