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IN the course of his employment the Broken Hill Co. the writer has had occasion to use and instruct others in the use of the Shamrock rescue apparatus. This paper deals with the various types of apparatus tested. The common object of the various types of breathing apparatus is to enable the wearer to remain and work for varying periods of time in an atmosphere which is either deficient in oxygen or is poisonous that is, contains carbon monoxide or irritating and irrespirable vapours, such as the smoke from underground fires, sulphur dioxide or ammonia fumes. For any apparatus to be efficient as required in the above paragraph it must fulfil the following conditions;1. Air-tight as regards the passage of the air from the outside to the inside. In atmosphere containing carbon dioxide a slight leak would not render the apparatus useless; but where irritating vapours, such as the smoke from burning oregon and sulphides, are met with, even the slightest leak must be avoided.2. The oxygen supply must be ample, and so supplied that it is not checked by expiration.3. Expiration and inspiration must not be retarded.

Jan 1, 1911

By Miller JD, Ye Y

The Air-Sparged Hydrocyclone (ASH) has been developed for the fast and efficient flotation of fine mineral particles in a centrifugal field during the past decade at the University of Utah. Over the years, the air-sparged hydrocyclone unit has shown promising potential for the flotation of copper porphyry ore, low-grade placer gold and auriferous pyrite ores, various industrial minerals, and fine coal cleaning. Many fundamental studies including the X-ray computed tomography (CT) analysis have been carried out in order to understand the multiphase fluid flow phenomena associated with ASH flotation. With data available from these studies, it is now possible to construct more accurate ASH flotation models for different applications in order to analyse the behaviour of the system and to optimise design and operating variables. The ASH flotation model developed in this paper is based on the data given in `Air-Sparged Hydrocyclone/Advanced Froth Flotation Fine Coal Cleaning', Final Report, DOE Contract No DE-AC-88PC88853, submitted by Pennsylvania Electric Company (PENELEC), December 1989. Data from several hundred experiments with the two-inch ASH-2C air-sparged hydrocyclone (capacity 0.1 - 0.3 tph dry coal) are available from the report and have been used for this analysis. In the past, a preliminary model based on limited data had been developed. The current study, however, emphasises the global behaviour of the ASH system by utilising almost all the data from the report for the purpose of scale-up and industrial application. There are two parts in the current modeling and analysis effort for ASH flotation of fine coal. The first part is the modeling/analysis of dimensionless ratio of overflow opening area to underflow opening area, A*, and the dimensionless ratio of air flowrate to slurry flowrate, Q . The second part involves the modelling/analysis of all other variables in the system and an expert system for operation and control is introduced.

Jan 1, 1993

By T Muri

The drying operation of materials from particulate solids, through slurries and suspensions, to continuous sheets represents an important part of several processes in the chemical and mineral industries. The increasing demand of high productivity at low cost and minimal environmental impact makes it complex to evaluate and choose the best available drying technology for each industrial application. The drying technologies are mainly characterised on the basis of how the wet product is related to the drying medium, namely: direct and indirect drying. In the direct drying method (convection drying), the product is brought into direct contact with the drying medium, which may be hot gas or air. Large quantities of gas are necessary for transfer of the required energy. A special case of the direct dryer is the fluid bed dryer, in which the product floats on a cushion of air or gas. The process air is supplied to the bed through a perforated distributor plate and flows through the bed of solids at a velocity sufficient to support the weight of particles. Very high heat and mass transfer values are obtained as a result of the intimate contact with the solids and the relative velocities between individual particles and the fluidising gas. In the indirect drying method (conduction or contact drying), the wet product is separated from the drying medium. The drying unit can consist of a rotor forming the indirect contact heating surface mounted in a stationary or rotating shell. The indirect method uses saturated or superheated steam resulting in low energy consumption and minimal environmental impact. In this paper, a review is given of the technologies available on the market based on different drying methods. The advantages and the disadvantages are summarised with respect to issues such as investment and operating cost, maintenance, product capacity, product handling and environmental impact.

Jan 1, 2006

Extensive infrastructure construction works were required for the development of the underground and open-cut coal mine at Ulan to a production capacity of 5 million tonnes of steaming coal per annum. The Ulan Mine development project was constructed in a two year period at a cost of $240 million. The infrastructure component included the construction of the mine site building works, civil works and 150km of railway, valued at $105 million. These works were successfully completed under a construction management agreement within two years. The separate elements of the project are described in detail in the paper.

Jan 1, 1983

By Seeley D, Buckley N, Goodall J

Improving the performance and reducing the costs associated with export logistics chains is critical to the competitiveness of export coal mines. The fundamental practices associated with the use of export logistics chains made up of mine, trucking, rail and port operations are being challenged by the advent of third party operators on rail systems and the use of the Internet.Whilst individual mines can improve their processes to drive down their mining costs, they face major challenges in their endeavour to improve the performance of export logistics chains and reduce the significant logistics costs of moving coal from the mine to export ships, via the shared infrastructure of rail systems and ports. There is an increasing realisation that global competition is not only between mines but between coal export regions that are defined by their rail system and ports infrastructure.

Jan 1, 1998

This paper looks at the development in management education for engineers at the undergraduate level with particular reference to mining engineers. The management core content of the engineering degree course at Ballarat C.A.E. is described is some Detail.

Jan 1, 1986

By Felice J. J

The assessment of the face velocity of blasts is important in the analysis and subsequent improvement of blast performance. POWERWAVE RADAR is a new tool which will make the collection of this data easier for blast researchers. The data collection technique ensures that a large amount of face velocity data is collected from a blast, and describes the velocity characteristics of the face at a new level of detail. This results in a greater understanding of the effect of drilling and blasting parameters on blast performance. Several case studies are presented which illustrate the collection technique, the type of data generated and how the data is used.

Jan 1, 1992

The first step in the mining and processing of nearly any mineral ore is comminution. Since the oil embargo of 1979, the mining companies have been striving to reduce energy consumption and costs. The first serious step was the introduction of in-pit crushing in the early 1980s. With in-pit crushing accepted as a standard design mode, the energy saving emphasis turned to comminution practices. A great deal of attention has been focused on blasting and grinding. The one step that has not been addressed is the primary crusher. This paper will address the opportunities for comminution improvement through optimisation of the primary crusher.

Jan 1, 2004

By Kawatra SK

The incentive to control coal flotation circuits arises because of disturbances, from plant operating practices and variations in feed coal characteristics, which result in large amounts of fine coal being lost in circuit tailings streams and lower grade concentrates being produced. Additionally, the flowrates and compositions of con-centrates and tailings streams can have significant effects on dewater-ing brocesses. A universal control strategy for these circuits cannot be developed. Rather, three major groups of variables must be con-sidered during strategy development: coal characteristics; circuit design and operating practice; and the variables selected to control the process. The second. and third groups-are discussed in this paper and examples from studies in operating plants are presented.

Jan 1, 1985

By Richmond GD

The Hellyer concentrator of Aberfoyle Limited commenced production in 1989 processing a fine grained, massive sulphide ore containing Zn, Pb, Ag, Cu and Au as values. Four concentrates are produced - copper/silver, lead, zinc and bulk (Pb/Zn) - with overall payable recoveries (1991) of 80 per cent Zn, 55 per cent Pb, 50 per cent Ag, 30 per cent Cu and ten per cent Au. Metallurgical development work commenced immediately after plant commissioning, and continues. The flotation response and liberation analysis on a size basis highlighted reagent balance problems associated with tower mill regrinding of sphalerite, poor conditioning of flotation pulps, poor selectivity for fine galena, and insufficient liberation. These were the main causes of values lost to tailings, values reporting to the 'wrong' concentrates and of impurities in the concentrates. Modifications to tower mill regrind circuit operation, and the use of improved conditioning techniques have greatly improved concentrator performance, particularly in the finer (-5 micron) size fractions. Studies of concentrator and laboratory flotation by size and liberation analysis are the basis of diagnostic metallurgy. The techniques used to evaluate the improved concentrator performance are discussed.

Jan 1, 1993

IF lead be heated with concentrated sulphuric acid two distinct actions will usually be observed. In the first, bubbles begin to be evolved more or less rapidly from the lead, and in the second, which occurs at a higher temperature than the first, hydrogen and sulphur dioxide are evolved, free sulphur is liberated, and leadsulphate is formed. The second action may be violent and usually continues till the lead is all consumed.Attempts have been made to apply these reactions, by means of a standard procedure, as a "Flash test" for the acid resisting qualities of chemical sheet lead. The purpose of this article is to comment on the best method of performing the test, on the various phenomena which may be observed during the course of it and on the interpretation of the results when obtained.PREVIOUS WORKIn 1919, Barr...

Jan 1, 1930

By Bailey H. W

Power supply for remote mining developments is compared with supply to the general public with the conclusion that the private power plant operator has many opportunities to minimise his costs which are not open to public utilities. The main features of diesel, gas turbine and steam power plant and the limitation upon their application which may be imposed by the fuels available and the local conditions at remote sites are outlined. Reference is made to the value of joint examination by the mining engineer, metallurgist and power engineer to decide how to make best overall use of capital, labour and energy in co-ordinating the design of power and process plant and in setting no more than adequate standards of reliability and efficiency. Fluctuations in world markets make it difficult to plan mining operations to a firm time base. Suggestions are made to minimise the financial risk in forward expenditure upon power plant which in large sizes due to longer construction time may have to be ordered before a final decision is taken upon the mining development it is to serve.

Jan 1, 1973

I know the theme of the Congress is "The 21st Century - Mining for Mankind" but I hope you will understand why my address touches upon some near-term issues as well. With the world oil market the way it is at present, "the long term" seems to be next week and no one is even sure what will happen tomorrow! So I am going to take a little licence with the theme of the Congress and talk about some fundamental issues that have much to do with the current uncertainties. The ways in which these issues are resolved and the role governments elect to play in the next few years will determine both the shape of the petroleum industry in the 1990s and beyond and the success with which we can confront a growing and inevitable future dependence on OPEC oil resources. But just in case you are not familiar with what has been happening in the petroleum industry recently and why the future seems more uncertain than ever, let me show you the gyrations in oil prices over the past 13 years, and remember that it is only another 13 years or so years to the 21st Century.

Jan 1, 1986

By Mallett CW, Hobbs BE

This study examined the structures of the Bowen Basin in central Queensland, Australia, by a series of lineament analyses. These studies were carried out using published geological maps, NOAA-AVHRR imagery, and LANDSAT MSS. Comparisons between these various data sources allowed the discrimination of the nature of the observed lineament sets and the time of their development. These data, which have been verified by field work, allowed the development of an integrated structural model of the Basin as an area of compression. This is considered in the light of a plate tectonics framework for northeastern Australia. The study showed that geological structures of great significance to mining operations, such as strike slip faults and large thrusts, could be identified and mapped using a combination of satellite imagery and field investigation. The small scale view of the satellite imagery also facilitated the development of a structural model for the Bowen Basin.

Jan 1, 1986

Accidents in open pit mining have a high cost in lost time of person- nel, damage to equipment and installations, and lost production. The realities of export competition require that Mine Management sig- nificantly reduce the costs associated with accidents and workplace ill-health. Newer management approaches are proving effective in reducing the Total Cost of Risk through a strucured Occupational Health and Safety Programme exhibiting the following features: ò Formal Company Policy ò Accountability for OH&S performance clearly designated to each level of management and supervision ò Effective utilisation of a Mine Occupational Health and Safety Co- Ordinator and a Mine Occupational Health and Safety Adviser ò Development of realistic OH&S Objectives ò Training of Management, Supervision and Workforce in Occupa- tional Health and Safety ò Development and adoption of Safe Work Practices and Procedures ò Effective employee selection procedures, control of Contractors ò Monitoring of the health of the workforce ò Collection, recording and distributing information on all Mine inci- dents, accidents, injuries and damage ò Ensuring that the Mine environment is healthy and safe ò Effective Emergency Procedures to deal with injury, fire, rescue and other situations of risk ò Controlling those Mine hazards which cannot be removed ò Adopting a high standard of Occupational Rehabilitation ò On-going visible Management participation in the programme to ensure that momentum is developed and maintained. This approach requires that Occupational Health and Safety be given equal status with product quality, maintenance of plant and output per- formance; its implementation is rewarded with improved morale and major cost reductions.

Jan 1, 1989

By J Loeb, D Thornton

Blast movement measurement is a key component of grade control, enabling mines to carry all of the precision involved in locating ore blocks, through a chaotic blast, to production. A monitoring system was developed about ten years ago so that mine operation personnel can measure three dimensional movement in every production blast. Research has shown that blast movement is always highly variable with a significant non-deterministic component. The consequence is that modelling will be inaccurate and therefore optimal ore recovery can only be achieved by direct measurement of blast movement.Three dimensional movement vectors are measured at discrete locations in the blast. If blast movement is only measured at one location in a blast pattern, data is severely limited and has all of the inherent inaccuracies of modelling a variable population. It is intuitive that the accuracy of defining the post-blast ore block mark-ups are proportional to the number of movement measurement locations, however increasing the number of monitoring locations causes increases to the direct operating costs of the mine.A cost-benefit analysis is used to explore the optimal number of monitoring locations. Using the method described in this paper, an automated selection of the number and location of blast movement monitors are analysed against the value of recovered ore compared to the control, for each trial.CITATION:Loeb, J and Thornton, D, 2014. A cost benefit analysis to explore the optimal number of blast movement monitoring locations, in Proceedings Ninth International Mining Geology Conference 2014 , pp 441–450 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 18, 2014

By Denholm WT

The Dittmer process for the debismuthising of lead by electrolysis beneath molten caustic soda has been scaled up to 100 kg lots for batchwise operation and to 20 kg per hour for a continuous flow of lead. Bismuth was decreas- ed from 0.03 to less than 0.005 wt. per cent for an electricity consumption of 220 kWh per ton of lead. Lower bismuth levels may be readily achieved if required.

Jan 1, 1975

Modern Management Systems for Higher Margins By Malcolm Roberts, Catalyst for Corporate Performance Ltd Malcolm Roberts put the case for changing systems in order to change behaviours and attitudes and improve productivity. ""The key to lifting margins is changing systems."" A system is anything that drives ways of doing things. Sometimes these are formal, and documented, and sometimes they are not. Improving productivity The way to dramatically improve performance is to use the systems. Roberts stressed that if systems and processes are under control, the benefits of automation are huge. If they are not, the benefit of automation will be lost. To improve productivity, you need to: ò identify what to change in the process, ò use the proven methodology to systematically improve the process, and ò change what people do - change work practices.

Jan 1, 1997

Diversity is a key strength for Western Mining Corporation. An international corporation with assets of about $A10 billion, WMC is engaged in both mining and downstream processing of minerals including nickel, gold, alumina, copper and talc, as well as having interests in oil and gas production and agricultural fertiliser. The company is focusing on several core commodities that will maintain its strength in the years ahead. Although most current mineral assets are within Australia, it plans to have 25 per cent of its operations off-shore by the turn of the century, and be a major producer in at least six core commodities. WMC's strategic and management focus has shifted from a regional approach to a commodity focus so that it can more readily cater for different markets with differing sensitivities. This document is an ABSTRACT ONLY - no paper was published for this presentation

Jan 1, 1996

Peko Mines, a Division of Peko-Wallsend Operations Limited (PWOL) has operated several small underground mines in the Tennant Creek district of the Northern Territory supplying ore to a central treatment plant. The Argo Mine is the most recently developed by Peko Mines. A magnetic anomaly was identified from low level airborne magnetics in 1960 and drilling, which commenced on the site in 1969, was halted in 1974 and resumed in 1980 following the rise in the price of gold. By mid 1983 a resource of + 200 000 tonnes of 12 g/tonne Au had been outlined and a decision to develop the resource was taken following the drilling of three further diamond drill holes which did not significantly alter the value of the resource. The small size of the orebody could not support the full capital cost of two shafts and a single entry mine plan was developed to extract the ore at a rate of 15 000 tonnes per month and to provide all the safety features, ventilation systems and services of a two shaft mine. In December 1983 a contract was let to Allied Constructions Pty. Limited (Allied) to sink and equip a 4.8m shaft to a depth of 410m and to convert the headframe and winder, which are leased for the life of the mine by PWOL from Allied, from a sinking to a production configuration. Shaft equipment designed by Hardcastle & Richards Pty. Ltd. (H & R) in conjunction with PWOL includes a skip/cage, counter- weight, and an auxiliary cage on rope guides, a sealed ladderway and exhaust air ducts.

Jan 1, 1986