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By James CH

For drainage sediment to be used as a successful sampling medium in reconnaissance geochemical surveys, the length of any dispersion train from a typical target must be great enough for it to be detected by a widely spaced sampling pattern, and must also be homogeneous enough to avoid it being missed by the unfortunate selection of a random low value sample. Elements which occur in stream sediments in the form of discrete heavy minerals present two special problems in this regard. Since the element is concentrated into a few particles, the medium is extremely heterogeneous, which makes representative sampling impossible unless very large samples are taken, while the high specific gravity of such grains leads to their being concentrated in traps along the stream bed. Several ways of overcoming these difficulties have been suggested. Among these the "schlich" test, in which heavy material obtained by panning is taken for analysis is among the most popular. However, the results of the present study indicate that while this method improves the nature of the patterns obtained, they are still far from satisfactory. Alternative methods of sample preparation, including the taking of light material for analysis, appear to provide better answers to the problem. In the area studied this approach eliminated most of the "noise" associated with the data obtained by other methods, as well as giving an extended dispersion pattern.

Jan 1, 1986

By Moxon N. T

A series of low shock energy water resistant emlulsion based explosives have been developed by combining inert materials, such as Perlite P500, into the formulation. The material handling, water resistance and explosive properties of these mixtures were determined as a function of inert additive type, density, charge diameter and emulsion base. Of the emulsion bases tested Emulite produced the best and most stable low density mixtures ranging in density from 0.8 to 1.35 g/cm3 producing velocity of detonations (unconfined) ranging from 3000 to 5500 nits. The mixtures could be detonated successfully at these densities at diameters as low as 25mm. Low shock mixtures formed by combining Emulite with Perlite P500 were successfully trailed at the Cadjebut zinc mine in Western Australia. The performance of the explosive, at three densities, was monitored using both continuous and point to point VOD techniques. The fragmentation produced by the blasts were compared by photographic analysis. During this trial the low shock emulsion mixtures were shown to be as effective as the currently used explosives (packaged emulsion) at a significantly reduced cost.

Jan 1, 1990

By Hori M, Komatsu T

In Japan, a small-diameter tunnel boring machine (TBM) of diameter 2.6 m applicable to a wide range of geology from hard rock to soft strata was developed with the purpose of reducing construction costs of headrace tunnels for small hydroelectric power stations. And in 1983, a demonstration test was carried out in the No. 1 headrace tunnel work of Hayakido Hydroelectric Power Station. The principal achievements in executing work are the following: (1) Although this TBM was a demonstration test unit, excavation advances averaged more than 200 m/month and exceeded the average 150 m/month with a conventional method. (2) According to PS velocity surveys after tunnel excavation the zone of loosening due to the TBM method was small enough to be ignored and was approximately one-half compared with conventional methods in rock of the same evaluation.

Jan 1, 1987

Indiscriminate surface disposal of coal waste in New South Wales has created a serious fire hazard and increased air pollution.A survey of numerous dumps, as well as particular investigations of one badly-constructed dump, showed that factors conducive to ignition and propagation of fires in waste dumps were high contents of combustible material (coal, pyrite, wood. paper. grease), size segregation leading to ready movement of air and moisture shape of the dump (e.g. protruding sections or porous junctions), high ambient air temperatures, bush fires, and even deliberate lighting.Control methods applied in the past tended to be haphazard and unsuccessful. Under Australian conditions the technique recommended for control of existing dump fires, based on experimental work, is to spray the dump with a chemical fire retardant (e.g. a 2 per cent solution of sodium tetra borate and ammonium phosphate), to cover the dump with a suitable soil, and to seal the surface with a I per cent solution of aluminium sulphate or sodium metasilicate. The recommended method of dump construction to prevent fires is to level and seal the site, to construct a firebreak around the dump area, and to build a rectangular dump with minimum size segregation and compacted surfaces.

Jan 1, 1971

By Bunting HR

Developments since 1959 in major excavators to meet the high outputs of overburden and coal under the changing nature of the Morwell Coal Deposits of the Latrobe Valley are described. Particular reference is made to investigations of designs of the bucket wheel head configurations for the digging of flat batters on high faces, and examples are given of the wide use ofmodelsin these studies.An explanation is given of considerations leading to selection of the Long Boom or the Compact type of bucket wheel excavator for various applications. The past decade has seen increasing manufacture in Australia of components for excavators and similar machines. The measures undertaken to integrate these components with those from overseas (Germany) are described. A section of the paper deals with advances in Electrical Engineering for large excavators in Australia and its interdependenee with mechanical design and construction. Finally, as an example of the versatility of the bucket wheel excavator a description is given of a recent application for the mining of mineral sands in Northern N.S.W.

Jan 1, 1970

By Irving R. C

THE objective of the iron smelter is naturally the production of high quality iron at the lowest practicable cost. To enable this, large tonnages are put through the blast furnace, and, at the same time, the quality of the iron must be under definite control.The modern blast furnace enables these objectives to be attained. The description whieh follows sets out the general details of construction of such furnaces, and the operation at thc Broken Hill Proprietary Company's blast furnaces at Newcastle, New South Wales.The occurence of iron in many forms is so well known as to need no description. Modern civilisation may be said to be built on a foundation of iron, and, today, the production of iron and steel has beeome one of the world's industries.A short historical introduction will serve to show the evolution of the processes and apparatus since iron production assumed importance.There is no definite date fixed as to when iron was first made, or by what means it was first discovered. Perhaps prehistoric man threw iron bearing stone on to his fire, and these became reduced, Ieaving a soft metal behind, or more probably the first iron was of meteoric origin.There is evidence, however, to prove that it has been known for a period of 6000 years. Iron has been found in the Pyramids and its use was known to the early Eqyptians and later to the Hebrews, Assyrians, Greeks and Chinese. Following the Greeks, the Romans excelled in its extraction and uses in the manufacture of their instruments of war, and to this fact can largely be attributed the success of their many wars of conquest. As the Romans overran the rest of the then known world they carried the art with...

Jan 1, 1930

By Batterham R. J

Some developments in copper, lead and zinc extractive metallurgy which have gone in to production or seem to be close to production scale are described with emphasis on why these innovations have been adopted.Mineral processing operations are now using: automated quantitative mineralogy,high capacity fine crushing equipment, ò fine grinding equipment, andcolumn cell flotation.Extractive metallurgy plants are using:ò bath smelting of concentrate at various scales, and ò flash converting of copper.Hydrometallurgical process developments are slower to make a commercial impact. Concerns about ability to handle impurities in the feed and production of saleable by-products are often major hurdles.An expression for the probability of implementing the first example of a new development is presented.

Jan 1, 1992

Recent work on computerised mineral resource databases at the Institute of Geological and Nuclear Sciences Limited has concentrated on the development of the GERM, REGCHEM, and MINLIT databases, and their integration in a Geographic Information System using MapInfo software on an IBM-compatible microcomputer local area network. GERM (GEological Resource Map) is a mineral deposit inventory with national coverage and more than 10 300 entries. REGCHEM (REGional Exploration GeoCHEMistry) is a database of stream sediment analyses from open-file mining company reports, containing more than 14 000 sample sites from the Coromandel and west Nelson regions. MINLIT (MINeral LITerature bibliography) is an annotated bibliography of literature on topics relating to the exploration and geology of mineral deposits in New Zealand, and includes more than 5000 entries for published books and papers, and unpublished mining company reports, university theses, and government reports. Master sets of GERM and MINLIT continue to be maintained on a VAX mainframe network but REGCHEM is operated only in the PC environment using the Microsoft ACCESS database management system software.

Jan 1, 1993

By C G. Sweeney

The underground mining industry is seeing unprecedented shortages in skilled labour. Migration to Australia being at an all-time low is a leading concern, with pandemic-induced border closures and lockdowns only exacerbating the skills shortage, not causing it. The skills shortage is forecast to peak in 2023 and remain high beyond 2025. With this skills shortage in mind, mining companies throughout Australia are trying to deal with stricter protocols around Health and Safety (H&S) legislation, as well as more stringent controls on quality assurance, particularly as underground mines are reaching greater depths and extending into ‘unchartered territory’. The cumulation of this is proving to be a major hurdle in ‘effective’ operational geotechnical management. The drive for automation in mining is bringing another level of complexity. However, ‘once automation is up and running, it presents the opportunity to access talent pools that may not normally be available. There is also a change in skillset that will be required to drive automation. ‘The top two emerging roles that will be critical for the future of the mining industry are artificial intelligence and machine learning (AI/ML) specialists, and process-automation specialists’ (Writer, 2021). If anything positive has come from the pandemic, it has shown that remote working can be effective and that the drive for automation and critical evaluation of skills required on-site should be given greater priority. UQ acknowledges that the industry is changing, and that digital technology is required to be offered in mining related disciplines. Industry and academia need to do more to promote geotechnical engineering in mining and balance the curriculum to suit the future of mining and make it more enticing. The average cost of a geotechnical failure is about $5 million in coalmines and can be into the hundreds of millions of dollars if production is affected (Cartledge Mining and Geotechnics, 2020). The cost of a good geotechnical design far outweighs the potential losses if a failure were to occur. This alludes to the growing importance of experienced geotechnical consultancies playing a pivotal role in managing mine site geotechnical hazards, while the industry is developing the next generation of geotechnical engineers.

Nov 29, 2022

By Corbett GJ, Leach TM

A continued exploration programme has further defined the geology of the Tolukuma vein system, verified the resource indicated by Newmont, and identified potential for additional mineralisation. The resource at Tolukuma Hill, designated as zone C, is a mine recoverable 432,000 t at 18.1 g/t Au & 46 g/t Ag. Mining will be by a combination of open pit and underground at a rate of 100,000 t per annum. Processing will be by SAG mill, gravity circuit and CIL plant. A diatreme breccia, localised at an intersection of structures and a relationship of gold to base metal sulphides, are indicative of a strong porphyry association. Typical epithermal features such as crustiform banded quartz and quartz pseudomorphing platy calcite are also present and locally contain lesser gold mineralisation. Pre-existing dilatant structures have acted as a host to the ore fluids, resulting in the formation of the semi-continuous Tolukuma-Gulbadi veins over a 1100 in strike. A fluid flow model suggests that mineralizing fluids were sourced from a diatreme margin and migrated laterally along dilatant structures. Bonanza gold grades are interpreted to be derived through fluid quenching in the flexure between a hanging wall split, which hosts much of the Tolukuma Hill resource, and the feeder graben structure. Thus, the relationship between the pre-mineral structural geometry and fluid upflow at the margins of a diatreme breccia, controls the ore setting.

Jan 1, 1995

By Doyle P, Mulroney D

The Cassidy Shaft was sunk to access the Mount Charlotte and Reward Orebodies below the Flanagan Fault. The 1,184m deep shaft is concrete lined to 6.5m diameter for its full depth. The initial 590m was excavated by stripping into a 1.8m diameter borehole and hoisting the broken material through the existing mine. The remaining 594m was excavated by conventional shaft sinking methods. The shaft was sunk through 3 existing plats and an additional 8 plats cut. 1,800 tonnes of steel and 8 cables were installed during the furnishing of the 4 compartments.

Jan 1, 1985

By Ehlert G, Steinlechner E

The paper describes a new process for filtration which combines the continuous operation of conventional vacuum filters with the low final moisture contents hitherto only achievable with plate and frame presses. The increasingly high portion of fine particles causes several problems in the filtration of copper concentrates. One drawback is that remarkable quantities of liquid are attached to the very fine particles because of their specific surface area. Furthermore, fine particles also reduce the size of the capillaries in the filter cake, thus increasing the critical pressure which any filtration system has to exceed to achieve the desired final cake moisture. The maximum filtration pressure of conventional vacuum filters is limited by nature itself and by practical aspects to approximately 0.75 bar. The hyperbaric filter combines the continuous operating principle with an increase in filtration pressure of up to 6 bar simply by placing the entire disc or drum filter inside a pressure vessel. The major machine components and process features are explained in the details of the paper. After extensive research and field testing, 23 ANDRITZ hyperbaric filters, with a total filtration area of 1968 m2 have now been sold. Seventeen of these units (1440 m2) are in commercial use and more units are, on order. Performance data on copper concentrates from plants in Australia, South America, Poland, Africa and North America are outlined in detail. Compared to vacuum filters, generally hyperbaric filters will reduce the final cake moisture of concentrates with 75 per cent

Jan 1, 1993

The extinction of zinc from steelmaking dusts has been studied with a laboratory scale reduction-vapour deposition (RVD) process in the absolute pressure and temperature ranges of 13 - 1300 Pa and 1333 - 1513 K respectively. This process consists of pre-reduction of iron oxide by carbonaceous agent, carbothermic reduction of zinc oxide under reduced pressure to produce zinc deposits and subsequent re-evaporation of the deposits to liquedify the zinc. In the RVD, the gas mixture of Zn and CO quenched from the hot zone is separated into Zn deposit and CO which is transferred to the pumping system. The Zn are a layer of fine metallic zinc powders accumulated on the cold wall and removed to the vacuum distillation chamber. The experimental works have been carried out according to the following items: carbothennic reduction of zinc oxide under vacuum, carbothermic reduction o zinc ferrite under vacuum, and 3. distillation of the Zn deposits. It has been concluded from these experimental results that the recovery of metallic zinc from the EAF dusts is successful by this process, and a new concept for a practical zinc winning process has been proposed.

Jan 1, 1993

By Svensson J

The nickel segregation process is one of the methods for treating nickel oxide ores. In this process nickel oxide ores are heated together with a small amount of the carbonaceous reductants and halides to about 800-950¦C. The reduced nickel segregates onto the surface of the carbonaceous reductants in the form of metallic particles which are recovered by magnetic separation or flotation. Pilot plant tests for the extraction of nickel from nickel oxide ores have been made using nickel segregation process by means of a new roasting installation which is called the "Mechanical Kiln" (2.5m~ x 3m,') with autogenous heating. Nickel oxide ores containing about 2.5%Ni were mixed with 2.5%CaC12 and 2.7%coal, and continuously charged into this installation at the rate of 60kg/h in continuous operation for 30 days per trial.

Jan 1, 1980

By Schiller J. C, Both R. A

Base metal mineralisation occurs at several locations within the regionally metamorphosed Kanmantoo Group on the southeastern flank of the Mount Lofty Ranges between Kanmantoo and Strathalbyn, 50 km southeast of Adelaide. Sulphide mineralisation is of three main types (Seccombe et al, 1985):1. copper deposits, at the Kanmantoo and Bremer mines, South Hill prospect and several minor occurrences,2. lead-zinc deposits at Aclare, Wheal Ellen, Strathalbyn, St. Ives, Scott's Creek, and Glenalbyn mines,3. pyrite-pyrrhotite mineralisation of the Nairne pyrite deposit and many other pyritic schist units within the Kanmantoo Group.Syntheses of folding, metamorphism and stratigraphy of the Kanmantoo Group were given by Kleeman and Skinner (1958), Offler (1960, 1963), Offler and Fleming (1968), Marlow (1975), Mancktelow (1979) and Parker (1986). Studies of the general relationships of mineralisation to structure in the Kanmantoo area were given by Grasso and McManus (1954), Mirams (1962), Poole (1969), and Lindqvist (1969).Several conflicting views on the origin of mineralisation in the Kanmantoo Group have been proposed. Thomson (1975) considered much of the mineralisation as a late-stage product of regional metamorphism and he, like Parker (1986) and Lambert et al (1987), stressed the importance of major lineaments as an ore control. However, Lindqvist (1969) and Verwoerd and Cleghorn (1975) tentatively suggested a syn-sedimentary origin to the Kanmantoo copper deposit and Jensen and Whittle (1969) and Seccombe et al. (1985) on the basis of sulphur isotope data proposed a bacteriogenic sulphur source and a sedimentary origin for sulphides in the Nairne pyrite deposit. The latter suggested that most copper deposits represent stockwork, vein or disseminated zones within subsurface vents whereas massive mineralisation at Wheal Ellen and Aclare mines probably accumulated on the ocean floor.This paper presents new geological information on the structural and metamorphic setting of the base metal deposits and attemptsto relate this information to previous regional studies of the Kanmantoo Group. Estimates of pressure and temperatureof peak metamorphic conditions based on silicate mineral stabilities are considered in relation to various silicate and sulphidegeothermometers which have not previously been applied to rocks in the Kanmantoo Group.

Jan 1, 1988

By P M. Hetherington, F A. Pym, M P. Murphy, K E. Crook

Consultants in the mining industry have the opportunity to visit interesting deposits all over the world. Each deposit has its own set of challenges to face when it comes to defining and understanding the deposit geology and the economics to make it viable for extraction. Some of the challenges can include appropriate data capture, sampling techniques, structural characteristics, geochemistry, geophysics, lithology definition, and economic boundaries. It is essential that the practices used at each deposit (eg drilling, sampling, geological modelling, resource estimation etc) are documented and the results obtained are robust and defensible. The Competent Person is not always aware of instances where their resource estimation practices have not been substantiated. ‘You don’t know what you don’t know’ is a phrase frequently used during a mineral resource audit. Technical work to substantiate drilling, sampling, density, assaying, geological modelling and estimation processes is not always completed. Audited Competent Persons often comment: • ‘I was unaware that this was required.’ • ‘I have not had training in this area and do not know how to complete the checks required.’ • ‘This is how we’ve always done it.’ Examples of audits where it was found that geological practices were not substantiated are examined here. A discussion is included on why substantiation of these practices is important, and potential reasons as to why there are instances of unsubstantiated processes and practices are discussed.

Mar 22, 2022

By Kuzmitch O, Morozov A

The main direction in the mechanisation in the mines of the Donbas and the USSR is long-face technology with complexes on the base of hydraulic supports. On the base of the 30 year old experience of exploitation of the coal clearing systems the serious data about the behaviour of the contained rock, display of underground pressure 'on longwalls and preparatory workings have been accumulated. Exploitation works in mines of the USSR are carried out at different depths: from 1000m to 1200m. There are 26 mines in Donbas, which exceed the depth of 1000m. It is the mines of Donbas, where is a rich experience of the exploitation of coal seams in various conditions. Besides, there are wide variations on the factors of the extraction thickness, depth of seam, angle of dip, occurrence of gas dynamics and others. In many scientific establishments, and in Donetsk Polytechnical Institute also, there are scientific research/results, which can be of interest for the coal mining countries.The volume of coal mining from longwall system-mechanised walls in Donbas became stable at the end of the 70s at level of 70 percent. All the efforts to increase this level have not given any notable results, not saying about the technical-economical data, which gradually deteriorate. It shows that positive progress in using the technology for the long walls is over and it is necessary to find new ways of mechanisation of coal winning.

Jan 1, 1991

By T Dawson, B Haskins

Fatigue is it the newest buzz word or is fatigue a real phenomenon that is creating safety and organisational risk for you? There is no debate that fatigue is natural, and it affects us all, just like gravity; however, there has been much debate on the severity of its impact in the workplace. For many years the impact was not measurable, hidden out of sight and, quite frankly, written off as the infamous ‘operator error’. Over the last several years, advancements in technology have provided safety and health professionals, sleep scientists, fatigue experts and organisations with the ability to monitor and detect fatigue events in real time, as well as predict and monitor increased risk for fatigue events. Caterpillar Safety Services has assembled an extensive and exceptional set of technologies that will provide the best methods and data to measure the impact of fatigue. This paper will discuss fatigue in the workplace and review the technologies and data sets available, which will allow the reader to determine whether this risk is real or rubbish.CITATION:Haskins, B and Dawson, T, 2017. Fatigue risk in your operations – real or rubbish? It actually depends , in Proceedings 13th AusIMM Underground Operators’ Conference 2017, pp 137–142 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 16, 2017

By T G. Neville, G Terrey, J Burns

This paper explores recent industry training programs and lessons for supervisors. The Belbin Team Role model was used to increase participants’ awareness of behaviour and its application. The application of the Belbin model to underground, open cut mine and quarry supervisors is discussed.The key to team success may rest with the expertise and experience of its members, but increasingly effectiveness depends on how team members understand, acknowledge and support each other’s behavioural strengths. Discovering strengths is a challenge, both for their measurement and for the encouragement of team members to use the knowledge of themselves and others in the team. Using behavioural models provides a constructive approach and a language for supervisors as they build personal motivation and engagement.Prima facie, the mineral industry’s work may be too vigorous for teams and their managers could be more prone to use ‘solo’ or traditional management styles. Managers and supervisors must know when work allocated to a team is appropriate or where individual effort should be applauded and rewarded. For practical people with well-developed technical skills, improving the soft skills necessary for a supervisor requires some reflection and effort. The Belbin behavioural model can be an effective tool for recognising characteristics that can assist teams to be more productive.Experiencing the Belbin Team Role model as part of an industry qualification is important for supervisors studying to refine their team leadership skills. Data are available for participants to assess the nature of their teams and to confront the appropriateness of the behavioural mix for the work of the team and its individual members.So what are the next steps? All team development must have a place in the strategic thinking and plans of the enterprise. This needs a visible presence of senior managers and supervisors in managing a team culture with practical links to workplace priorities and professional development with continuous improvement.CITATION:Burns, J, Terrey, G and Neville, T G, 2016. Supervisors and teams at work, in Proceedings International Mine Management Conference, pp 125-138 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 22, 2016

By M Malec, J Szczerbinski

Hazards in underground mines are concomitant with the mining of mineral deposits and have their source in a minerÆs work environment. The authors of the paper have undertaken a trial classification of these hazards into three groups, depending on the sphere of their occurrence:lithosphere, ie rock mass, atmosphere, ie air in mine workings, and technosphere, ie machines, equipment and facilities in mine workings. The lithosphere creates such hazards as bumps, rock outbursts, the atmosphere is a factor causing fires, methane explosions and climatic hazards, whereas accidents concomitant with an operation of machines and equipment occur in the technosphere. Assuming that the number of accidents in the mining industry, concomitant with hazards, reflects the degree of safety, it has been shown, that in Poland they are under control to a large extent.

Jan 1, 1999