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Results are presented of the investigation of gas dynamics of the blast furnace process obtained on laboratory models and operating furnaces. Gas residence times were measured using a helium tracer technique developed for the purpose. Residence times were determined in furnaces of 1007 m3 and 1719 m3 and results used in the calculation of the burden parameters and to estimate the distribution of the gas flow along the furnace radius. The effect of tuyere injection of coal dust on gas distribution was also investigated and the advantage of continuous injection compared with intermittent injection is noted. The unevenness of gas distribution across the furnace area is found to correlate well with differences in the size analysis of the iron-bearing component of the burden. The mixing of the gas streams between the neighbouring raceways was studied. It is shown that in the central region of the furnace gases from every tuyere are mixed together, whilst in the peripheral regions mixing is more localised and includes only the sections consisting of five adjacent tuyeres. A solution is proposed to the problem of a theoretical evaluation of the critical gas velocity. A simple relationship between the Reynolds and the Archimedes numbers was obtained from which, after substitution of the burden size data and the gas parameters, it is -possible to evaluate the critical gas velocity. Conclusions include information relating to the optimisation of the gas distribution and views on reducing gas injection at elevated furnace levels.

Jan 1, 1975

By Ross J. F

A pillar 'is a block of coal left in the first working of a coal seam for the purpose of supporting the superincumbent strata in such a manner that the winning out roadways will be safe to traverse by men and by the coal transport system.PRINCIPLES OF PILLAR EXTRACTION.The size of a pillar is chiefly dependent on the depth of cover, and in a lesser degree on the nature of the coal, or the condition in which the seam has been laid down. In a seam at 1,100ft. depth of cover, and assuming a spec'ific gravity of 2.5 overall for the cover strata, a pressure of 1,200lb. per sq. in. is the loading on the top surface of the coal seam before mining begins.When mining commences, and as the pillars are formed, an increased load is imposed on the coal left in the pillars, according to the percentage of coal extracted in the first working. Thus, if 25% extraction is taken in the first working, the load on the pillars is theoretically increased from 1,200lb. per sq. in. to 1,600lb. per sq. in. over the area mined. If this state of things went on indefinitely it would not be possible wholly to extract a pillar because of the extreme pressure tliat would be thrown on the diminishing portion; but, fortunately, another element, that of time, enters into and assists the process of extraction.If the superimposed strata were of an entirely plastic nature, this time factor could not operate, as the cover weight would settle instantly on the remaining portion of the p'illar and finally overwhelm it. The cover strata above a pillar generally have a certain rigidity which does not allow the superimposed weight to settle instantly on the pillar fraction, and it requires a period of time to elapse before the extra weight is felt by the pillar.The time factor varies widely, and is governed entirely by local conditions; it can only be determined by experience gained on the spot or in close proximity to the area of operations. It is dependent on the strength of the strata and its characteristics under bridging conditions.It is, therefore, logical to assume that the more rapidly a pillar can be extracted the greater will be the safety factor and also the percentage of recovery of coal.Up to the present time, the operation of the extraction of pillars in this country has been, with a few exceptions, a manual one, and before mechanization of Collieries can be fully accomplished, the process will have to be performed mecharrically.

Jan 1, 1947

By Cole RT

The cultural ages of man have been defined in terms of smelting and hence as a prerequisite, mining for example the iron age and the bronze age. There could be no separation of the man from his role as the technologist (miner/ smelter) for his early metal working efforts were to enhance survival. In the millenniums since, the artisan specialist developed and the technologist emerged. The process is a sort of technical natural selection. From the generalist hunter, gatherer, miner, metalworker we advanced over the centuries with great 'steps for mankind' to the series of specialists each largely intent on securing his/her technical functions from the curious assaults of other tribal members. The relevance of all this to the theme, 'Past, present and future of the Victorian mining and metallurgical industries', is simply that people have always, and will always, be the moving force in our industries. It is the effectiveness of people now and in the future that this paper addresses.

Jan 1, 1982

By S Leary

Diamond drilling since early 2006 has identified an epithermal gold-silver (Au-Ag) deposit beneath 140 m to >400 m of cover. The Fruta del Norte discovery had an inferred resource estimate of 58.9 Mt grading 7.2 g/t Au in October 2007. The mineralisation is hosted by Mid-Late Jurassic andesite and andesite porphyry in a regional fault zone beneath mainly post-mineral but in part syn-mineral Late Jurassic cover. The intermediate sulfidation-style deposit formed before and in part during deposition of epiclastic cover in the fault related pull apart basin. In addition to its size and obvious economic importance, the widespread occurrences of visible gold and exquisitely preserved epithermal textures will make Fruta del Norte an important learning tool for explorationists seeking epithermal mineralisation in theAndes and elsewhere. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

By C Rees, M Predebon, J Denney

It has been said on many occasions that æthe future of the mining industry of Australia, and indeed the world, lies in the hands of the studentsÆ. As a student, this can be a daunting, yet very exciting, statement. If nothing else, it is a direct challenge to the student body of the mining industry to take responsibility for its direction æafter 2000Æ. However, for the students to embrace this challenge, some responsibility must be borne by the universities and the industry itself to provide some direction and encouragement. Perhaps, therefore, the real challenge is to find the right balance between students, industry and education to best prepare the students for a career in the mining industry. The future industry will demand students who are capable and willing to adapt to change and technology and able to exert the vision and leadership required to ensure the mining industry continues to thrive well into the next century.

Jan 1, 2000

By S C. Dominy

The Minerals Education Australia program is offering a tertiary learning environment for the global mining industry. The Minerals Council of Australia has instigated this initiative, which is run by the Minerals Tertiary Education Council. The program is a pioneering partnership between the Australian minerals industry, Australian governments and key Australian universities. It is designed to deliver key undergraduate and postgraduate courses for tomorrowÆs minerals industry professionals in the fields of geoscience, mining and minerals engineering and metallurgy. The flagship course for geoscience professionals is the G3 Masters program. This is a coursework-based degree supported by the Minerals Tertiary Education Council, and a partnership between James Cook University, the University of Tasmania and the University of Western Australia. These partners represent the leading-edge providers of minerals geoscience education and R&D in Australia. The G3 program provides the full spectrum of post-graduate training skills in exploration, mining and economic geology topics.

Jan 1, 2003

By T E. Jeffries, M Zentilli, J STguel, C C. Wilkinson, B G. Rusk, V H. Vry

Laser ablation Inductively Coupled Plasma Mass Spectrometry (ICPMS) analysis of fluid inclusions trapping mineralising solutions in major porphyry-copper deposits indicates that copper concentrations can reach 103 - 104 ppm in both dilute, CO2-bearing fluids and in high salinity brines. Non-Cl transport of Cu is implicated. Au has been determined at 0.2 - 0.4 ppm in the low salinity fluids and may be co-transported with Cu. In contrast, high concentrations of Fe, Mn, Zn and Pb are only attained in brines and correlate strongly with Cl-indicating chloride transport. Physical and/or temporal separation of these fluid types can therefore producemetal fractionation within porphyry systems. Evidence concerning the behaviour of Mo is less clear but brine transport appears to be favoured; phase separation is one mechanism that may account for the fractionation of Mo from Cu and the formation of quartz-molybdenite veins. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

By Johnston RF

The motivation for, the structure of, and the overall features of a block release Graduate Diploma program designed for practising minerals engineers are outlined. It is demonstrated that because of the very specific subjects taught, the course has the potential to effect significant improvements in operating plant performance. Through lifting the skill level of the participants and therefore advancing their career prospects, the course can raise staff morale and improve plant performance and productivity in their work place.

Jan 1, 1993

The excessively high cost of production in underground coal mines has made the survival of many coal mines around the globe economically non-viable. The global competitive coal market speaks itself of the desirability of a lower operating cost in conjunction with a higher productivity performance, particularly in underground coal mines, and calls for an optimal production planning under a host of constraints. Such a task of optimal planning is not an easy exercise like that of traditional planning based merely on intuition, experience and subjective judgement. It essentially demands a thorough understanding of the complex interaction of mine sub-systems for judicious application of optimisation tools and techniques available with operations research. A few large mines around the globe have made an effective use of a sizeable number of operations research packaged programs for optimal decision-making (Grayson, 1989). The success of practical applications of operations research techniques made in a variety of mining problems in large mines in different parts of the world will hopefully make inroads to smaller mines in years to come. The present paper is an addition in the series of such applications of operations research tools to mining problems, particularly with reference to an underground coal mine in India. The paper is based on research work (Jawed, 1990) and deals with the development and use of a mathematical model for production planning in underground coal mines under multiple objective environment subject to a host of constraints.

Jan 1, 1995

By Sharwood M

Welcome to the morning of the second day of Minval '89. There are some three hundred and fifty of us here today. That represents certainly the most influential gathering of the mining and investment community in Sydney for a very long time, and on behalf of the Institute I bid you all a very great welcome. Due to the pilots' strike some of you have arrived by very unusual methods and others have travelled long distances. So for those of you that have made a special effort, thank you very much. Inevitably some people have not been able to get to Sydney and this has led to some minor programme changes. I'd like to thank our sponsors. Our underwriting sponsors are Energy Resources of Australia, Neil Cole & Associates, Resource Finance Corporation and Robertson Australia Limited, and to those firms thank you very much. To our major sponsors, County NatWest, I would like to say a particular thank you. County is the lead sponsor for Minval '89. They've :made an important contribution to the programme, and we're indebted to them for this support. We look forward to County's continuing involvement in the programme today. County NatWest is a major participant in the Australian equities markets and a growing merchant banking organisation in this country. It's parent organisation, National Westminster Bank, isa leading UK domiciled bank which is also active in Australia. This session is the Pancontinental Mining Ltd sponsored session, and I'd like to record the gratitude of the Australasian Institute of Mining and Metallurgy to Pancontinental for its generosity in sponsoring the session. This morning's session focuses on valuation and follows on from yesterday's proceedings which looked particularly at the impact of NCSC draft Policy Release Number 149. Robert de Crespigny, who was to have been the Chairman of this morning's session, has had some special problems with the pilots' strike.So we have the privilage to have in his stead Michael Sharwood.

Jan 1, 1989

The chief use of manganese ore is in the production of ferromanganese alloys for steelmaking. Manganese ores generally occur in tropical areas, which influences the type of treatment required. Present methods of treatment are relatively unsophist- icated but demands by customers for tighter specifications will necessitate the installation of gravity concentrator at many mines At present only limited tonnages of minus j in. product can be sold hence future development will centre around methods of producing an agglomerate satisfactory to the smelter.

Jan 1, 1969

With the evolution rate of technologies, earthmoving equipment users are establishing vision statements for their operation out to and in some cases beyond 2000. Autonomous systems are receiving a lot of 'press' - and rightly so, as they hold a potential for achieving quantum leaps in productivity and cost gains. Caterpillar feels that it is important that the infrastructure of on-board systems are understood and can be utilised more in the near term to `grow' a user up to the stage of autonomous operation.

Jan 1, 1997

University education in Australia is changing, driven by greater market orientation, reduced funding available per student, especially in the higher-cost minerals industry disciplines, and the call for more flexible delivery of subjects and courses to meet changing lifestyles and expectations. The opportunity exists for a true partnership to develop between industry, government and academia that will reshape minerals education in Australia and secure the future supply of the specialists industry needs to maintain international competitiveness. If this partnership does not emerge, it is anticipated that AustraliaÆs somewhat fragmented and unstable higher education system, especially in the disciplines of particular relevance to the minerals industry, will be put under further pressure so decreasing its effectiveness to produce quality graduates. The Minerals Council of Australia in 1998 published æBack from the BrinkÆ, a discussion paper which proposed strategies to build a world class minerals tertiary education system in Australia. Those strategies are now being implemented collaboratively with principal emphasis on the disciplines of mining engineering, metallurgy and earth science and as far as process is concerned, on the necessity to æcooperate to competeÆ. For metallurgy, the challenge is to integrate more closely undergraduate teaching with the existing world-class research centres and to link the tertiary institutions in such a manner that the strengths of all components are harnessed and then made available nationally in major population centres and at remote sites where appropriate. For industry the challenge is to build effective partnerships with the academic community that will enable and assist the agreed course of action to take place.

Jan 1, 2000

By W Gale

Rock and coal fractures together with micro seismic vibration is a common occurrence during mining, however, it is very uncommon for coal and rock to be propelled into the roadway. Irrespective, such occurrences do occur and appear to require significantly more energy than is available from strain energy release during coal cutting. The sources of energy which can contribute to the propulsion of coal from the face or ribs are typically strain energy from the surrounding ground, seismic energy from a rapid rupture of the ground in the vicinity, or rapid expansion of gas from within the burst source area. The aim of this presentation is to briefly review the mechanics of a coal burst and to discuss the mining situations for which the energy is sufficient to create bursts. A brief discussion of alleviation strategies is discussed. This is an abstract only. No full paper was prepared for this presentation. CITATION:Gale, W, 2018. An overview of coal burst phenomena, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), p 2 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

By R MacGillivray

The Golden Cross mine was an open-pit and underground gold and silver operation from December 1991 to April 1998. Closure of the mine has been based on an approach agreed among stakeholders. The initial phase was the release of a closure plan which was regarded as the blueprint for the following phases and the closure works required to implement the plan. The second phase involved lodgment of consent applications and their granting for the final water management configuration. The final phase is monitoring, confirmation that the site is performing as required by the closure plan and consents and settlement of final ownership, management and surety arrangements. Industry best practice modelling techniques have been used to finalise closure design and have been shown to be good predictors of site water management and discharge performance. Site discharges are in compliance with toxicology based water quality criteria for the protection of aquatic life and most discharges from the site, including those from the closed cyanide-tailings facility, can now be discharged without further active intervention or treatment.

Jan 1, 2002

By N Bennett

This paper examines the practical and economic benefits of using bulk emulsion explosives in underground development mining; compared to ANFO, ANFO derivatives and packaged explosives. The key economic benefit of bulk emulsion is the replacement of relatively high cost packaged explosives with a bulk product. Key practical benefits include water resistance, improved coupling of explosive, reduced toxic gas production, increased shock energy and improved manual handling through the use of bulk products. Each of the benefits is proven using a variety of measurements and field results in order to quantify them. Where possible, dollar values are determined so that the benefits can be shown to translate into savings for the mine operator. The results show that, despite the difference in price between ANFO and bulk emulsions, bulk emulsions are most capable of delivering the lowest total cost of blasting. The savings potential of the introduction of bulk emulsion systems can result in an improvement in drill and blast costs for a mine operator, or a significant increase in profit margin for a contract mining company.

Jan 1, 2007

By Somasundaran P

Controlled modification of mineral/liquid interfacial properties by adsorption is critical for mineral processing operations such as flotation, filtration, dispersion and flocculation. Ionic/nonionic surfactant mixtures usually show enhanced surface activity and salt tolerance over ionic surfactants, and this is especially beneficial for flotation of salt type minerals in which case dissolved multivalent cations in high concentrations usually cause loss of anionic surfactants by precipitation. Adsorption of nonionic/anionic surfactant mixtures on kaolinite has been studied with sodium dodecylsulfate as the anionic surfactant and octaethyleneglycol mono-n-dodecylether as the nonionic surfactant. Synergistic interaction between these surfactants was found to cause adsorption of the nonionic surfactant with its hydrophilic chains protruding into the bulk, leading to substantial changes in flotability and dispersion characteristics of kaolinite. Similarly, hydrophobicity changes are observed also' for silica particles upon adsorption of nonionic ethoxylated alcohols owing to possible changes in the orientation of the adsorbed surfactant species at the interface. Also, based on the results obtained with surfactant adsorption, a hydrophobically modified polymer was used successfully to disperse graphite particles in aqueous solution.

Jan 1, 1993

Dr David Dekker discussed the importance of a multidisciplinary approach to automation, the infrastructure required to support automation, and selecting the equipment for automation. Dekker stressed that automation involves a number of technologies. The mining industry is currently about part-way through the evolutionary process of achieving a fully integrated automation system. He pointed out that the final stages require parallel development of infrastructure such as mine communications. Technologies required for automation Automation systems consist of three parts: the gathering of information, the processing of that information, and taking action.

Jan 1, 1997

Traditional methods for calibrating the most customisable forms of GyÆs formula for the prediction of sampling variances involve a large amount of experimental work. This work is often extremely sensitive to outlier treatment and often relies on assumptions. A general methodology called æthe consistency methodÆ, however, has proven efficient in guiding these critical steps and adding objectivity to these subjective tasks. After a quick exposition of its principle, it is shown how it can also be used to reduce the amount of experimental work when dictated by budgets.

Jan 1, 2008

By Borkin AD, Yemelyanov MF, Otrozhdennova LA, Malinovskaya ND, Nechay LA, Koltunova TY

The results of investigations of reagent regimes and flotation machines to decrease the losses of valuable components in both coarse and fine particle classes during non-ferrous metal dressing are considered.

Jan 1, 1993