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The prevention of silicosis by metallic aluminium has been reported by Denny, Robson, and Irwin in two papers. The first was published in 1937; the second in 1939. The results definitely established that silicosis was prevented in animals by the inhalation of small quantities of aluminium. The present communication records subsequent progress in this field of research.HARMLESSNESS OF ALUMINIUMAnimal experiments having served their purpose, it became necessary to consider means to test the discovery on humans. A question for immediate consideration was: Is aluminium harmful to man when inhaled as a fine powder? While the animal experiments were reassuring, since they conclusively showed the powder to be innocuous when breathed by animals, it was, nevertheless, desirable to have additional reassurance with regard to its effect upon human beings.Through the courtesy of the Aluminium Company of America and especially the valued interest in this problem displayed by that Company's Director of Research, Dr. Francis C. Frary, a study was made of the records pertaining to the health of a group of 125 employees who had for many years been engaged in the manufacture of finely powdered, metallic aluminium for the paint and ink industries. The conditions were such that these employees had inhaled varying and oft-times very dense concentrations of this powder daily over periods ranging from 6 to 23 years, the average 101 the group being 12 years. X-ray pictures of their chests showed no abnormalities attributable to aluminium. Their general health seemed better than that of the 3,000 workers in other sections of the plant. In fact, the early films of three employees in this group of 125 showed shadows suggestive of minimal tuberculosis, which shadows were not discernible in films taken after considerable periods of exposure to aluminium powder.The harmlessness of aluminium was; by this study, reasonably well established at the outset, a finding subsequently verified by Ontario research on humans.PROPOSAL TO TREAT HUMAN SILICOSISBased upon these findings, a proposal to treat silicotics with aluminium was discussed by officials of the Mclntyre Mine and the Banting Institute.

Jan 1, 1945

A study of literature on the epidiorite dykes which transgress the Broken Hill lode and its wall rocks reveals a considerable diversity of thought regarding the time of emplacement of such dykes. In this paper it is deduced that the epidiorite dykes were formed at a late stage and were probably post-ore. Detailed mapping, sampling, and correlation of data from over 100 exposures substantiates this deduction. Physical disruption of the epidiorite dykes is indicated and some interaction of the epidiorite and ore at the time of intrusion is inferred.Further petrological study may confirm this.

Jan 1, 1968

Process Study on Some Ag-Cu-Pb-Zn Polymetallic Ore in South China

Sep 13, 2010

Polyacrylamide flocculating agent has been used in the Leaching Division 'of the Risdon Works of the Electrolytic Zinc Company of Australasia Limited since October, 1960. The number of thickeners in the continuous thickening stage was thereby reduced from eight to three. There has been an increase of 25 per cent in throughput and a reduction of solids in thickener over-flow from 3-4 g/l. solids to 0·5 g Ir. solids. Reagent addition has been at the rate of 0·25 lb Separan NP10 per ton solids.Additionally there has been a gain of 3 per cent in current efficiency as the direct result of the addition of Separan NP10 to purified cadmium sulphate solution priOl; to electrolysis for cadmium metal. A smoother deposit has resulted and it has been possible to increase deposition time between strippings from 47 to 71 hr. However, there has been a slight increase in the lead content of the cadmium metal produced.The use of Separan NP10 to settle copper bearing residue in a batch process stage has resulted in a five-fold increase in settlement rate and a reduction in purification cycle time.INTRODUCTIONThe Electrolytic Zinc Company of Australasia Limited, Risdon, Tasmania, produces zinc by electrolysis of purified zinc sulphate solution, the raw material being zinc sulphide concentrate. In the Risdon process (Van Arsdale, 1953; J ohnstone, 1953; Ross, 1949) the compound zinc ferrite (ZnO.Fe203) is formed during the concentrate roasting stage. When the roasted material is leached in dilute sulphuric acid the zinc ferrite is not attacked, and it remains as part of the insoluble leach residue, of which it may form as much as two-thirds of the whole. The remainder is mainly unroasted zinc sulphide, unleached zinc oxide, lead sulphate, gypsum, silver compounds etc. The zinc in the residue may be 10 per cent of that in the original concentrate.Continuous thickeners are used to recover the valuable residue from the impure zinc sulphate solution and the...

Jan 1, 1963

The oxidation of sulphide minerals in aqueous suspension is discussed from several viewpoints. Limitations of our present knowledge are pointed out, and several points where further information would be of special interest are mentioned.Firstly, some properties of minerals and their effect on oxidation are discussed. Properties of different species, such as crystal structure, lattice bonding, and "metallic" properties are mentioned, and then the effect of variation within a given species is discussed. The effect of physical factors, especially particle size, is also considered. Other variables discussed include the importance of solution composition, and its effect on the nature and rate of reaction, and the use of various oxidising agents. Some factors concerned with the whole system, such as temperature, pulp density and stirring rate are then considered.Finally, the nature of various oxidation products is discussed with reference to the kinetics of reaction and the nature of the rate limiting step. It is suggested that more attention should be paid to electrochemical explanations of the reaction mechanism.INTRODUCTIONKnowledge of the factors governing the rate of oxidation of sulphide minerals in aqueous suspension is a prerequisite for the effective control of many ore treatment operations. Rapid oxidation of sulphides is usually desired during the leaching of sulphide ores and concentrates, but in the cyanidation of gold ores, or in the leaching of uranium ores, any oxidation of sulphides may be regarded as an undesirable side reaction. Knowledge of many of the factors involved is also of interest in connection with the oxidation of sulphides in flotation circuits and in natural ore forming processes.Systems for which some reasonably quantitative data have been published are listed in Table 1. Qualitative...

Jan 1, 1961

The upper amphibolite-grade mctasediments of thc rinaroo area, North Queensland, form part of a regional aurcole to the large Tinaroo Batholith and are the stratigraphic equivalents of the Hodgkinson Formation of gencrally low metamorphic grade. There is no evidence of any lithological unconformity.The higher grade metasediments have a more complex deformation history than is typical for thc surrounding region and this may bc due to one or a combination of two factors; an additional strain componcnt associated wilh the intrusion of Ihe Tinaroo Batholith, or a more marked finite strain response to the overall regional stress field within hotter. more ductile rocks.Four deformational events can be characterized within Ihc Tinaroo Area. Close to Ihe Tinaroo Batholith D1 and D2, arc so strongly developed that they disrupl the continuily of Ihe original Iithological layering. In the aureole region, D1 is strongly overprinted and its original fabric intensity is obscured, but both D2 and D3 display a mappable decrease in intensity away from the granite margin. These three deformations occurred during Carboniferous or early Permian time. D4 is later and only patchily developed.The broad, moderate pressure metamorphic aureole surrounding the Tinaroo Batholith is a typical of the CairnsCooktown group of Permo-Carboniferous granitoids. which usually develop narrow, lower pressure contact aureoles. Two periods of metamorphism are distinguishable. The first reached peak temperatures somewhat greater than 520°C, the second temperatures around 620-630° C immediately adjacent to the granite contact.Several cale-silicate lenses containing scattered scheelite mineralization occur within the area. Scheelite appears to have crystallized at the same time as the cale-silicate minerals, its appearance coinciding with the intrusion of the Tinaroo Batholith. Unlike many "skarn-type" scheelite deposits, the scheelite-bearing cale-silicates are Fe-poor, with no positive correlation between total Fe and W.

Jan 1, 1982

By J Law, S Jahanshahi, R Holmes

Iron ore is AustraliaÆs largest commodity export and is vitally important to AustraliaÆs current and future prosperity. However, while major expansions are currently in progress to satisfy demand, the industry is also undergoing major transformations. Reserves of traditional high-grade Brockman ores that have underpinned the Australian iron ore industry since its inception are slowly being depleted and alternative ore types such as Marra Mamba bedded iron deposits, Yandi and Pannawonica channel iron deposits and magnetite deposits are now being developed. However, the impurity levels in some of these alternative ores are higher and they require blending and/or upgrading as well as an advanced knowledge of their downstream processing characteristics to facilitate cost-effective utilisation by overseas customers. The research challenge is to use advanced techniques for mineral exploration, ore characterisation, mineral beneficiation, agglomeration and sustainable processing to identify and develop innovative and breakthrough options for locating, unlocking and enhancing the value of AustraliaÆs iron ore resources. Furthermore, to sustain the steel industry and hence secure the demand for iron ore, there is a growing need to enhance the environmental and business performance of the industry through reductions in wastes and emissions. Therefore, cost-effective breakthrough and enabling technologies that massively cut waste generation, CO2 emissions and water consumption are also being developed. These include the use of renewable fuels and reductants, waste heat recovery and conversion of by-product slag into a saleable substitute for Portland cement. A number of examples of recent developments in the above areas are provided in this paper.CITATION:Holmes, R, Jahanshahi, S and Law, J, 2013. Research and innovation for the iron ore to carbon steel value chain, in Proceedings Iron Ore 2013 , pp 3-6 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

By T Preston

Solid Energy is the largest coal producing company in New Zealand, employing 500 people and more than 250 mining contract personnel. The coal produced by Solid Energy plays a significant part in the energy mix for New Zealand being supplied to the coal-fired power station at Huntly. It is also supplied to a wide range of industrial users, NZ Steel, and primary processing. It is fair to say however that the positive economic and social benefits of coal have to some extent been overshadowed by the negative environmental consequences of coal mining.   Over the past two years Solid Energy have been actively researching and addressing the impacts that they currently have on the environment and making a significant investment in environmental improvements, rehabilitation projects and environmental research to address historical and ongoing environmental issues. These investments have been driven by the companyÆs commitment to its environmental policy, which states:   æSolid EnergyÆs overall environmental objective is for the cumulative result of all the activities we undertake to have a positive net effect on the New Zealand environmentÆ.   With such significant investment it is essential that the company is able to target expenditure wisely, ie invest where there is greatest environmental gain to be had, and are also able to actively demonstrate to stakeholders the improvements that are achieved. In order to be able to demonstrate the commitment and the steps that the company is making towards this goal a number of systems have been developed. Firstly an environmental management system along the lines of ISO14001 formalising the environmental processes, responsibilities, auditing and management review. Secondly as part of the planning element of the EMS an environmental management matrix, which allows the scoring of sites against environmental management goals, has been developed. Thirdly the monitoring and measuring tools have been upgraded with GIS driven relational databases installed for management of consent related information and monitoring results.   The development of the environmental management matrix has drawn on a number of existing systems such as the Australian Institute of Mining and Minerals Code 2000. In addition to adapting the scoring regimes from these methods the Solid Energy Environmental Matrix has been further developed to ensure that it reflects the actual environmental impacts on site, as well as the management and audit systems that are in place to control them at a strategic level. The development of this matrix has included a number of steps: +        reviewing the information that stakeholders would be interested in, +        reviewing what was already available, +        development of systems to collect data and benchmark the current         operations, and +        setting up support systems to ensure that the correct information would be provided for scoring.

Jan 1, 2004

Today computers are accepted as a standard item in industry and they perform a variety of tasks over a wide spectrum of activities from mine planning and CAD to data processing and spreadsheet work. However many problems particularly in the. area of decision making where there are no clear mathematical models available and usually the output or answer is dependent to some extent on a heuristic approach, don't lend themselves to conventional solutions using standard procedural algorithms. Recently a number of techniques have evolved primarily from the enhanced capabilities of modem equipment, which are capable of solving these problems. This paper is a brief overview of these rather unconventional developments of computer technology in the area of artificial intelligence with reference to their application in mining.

Jan 1, 1993

ALTHOUGH it has been a matter of about one hundred years since the idea of the internal-combustion engine entered the mind of the inventor, the practical application of its use was not attained till 1860, when Lenoir produced an engine similar to the ordinary highpressure steam engine, with the valves arranged to admit the explosive mixture and the discharge of the exhaust gases. In this case no attempt was made to compress the gas before ignition, as it was then considered that the explosion under these conditions had a detrimental effect, inasmuch as it would act as a sudden blow to the working parts. Indeed, he went so far as to inject steam and water sprays to reduce the explosion.Under these conditions the consumption of gas was exceedingly high-about 106 cub. ft. of coal gas per b.h.p. per hour but the mechanical effect showed that the engine ran in every respect as smoothly and quietly as in best steam-engine practice.The extravagant consumption of this engine was clearly pointed out at the time by Gustav Schmidt in a paper before the German Society of Engineers, wherein he states :-" The results would be far more favourable if compression pumps, worked from the engine, compressed the cold air and cold gas to three atmospheres before entrance into the cylinder. By this means a greater expansion and transformation of heat is possible."

Jan 1, 1912

By Ghosh I, Vanangamudi M

Experiments have been made in a laboratory heavy media separator at various specific gravities of separation using zinc chloride solution and magnetite suspension as media for different types of coals. The results indicate that the magnetite bath gives at better separation than zinc chloride solution. Even though the probable error remains the same for most conditions of operation, the error area is found to have a wide variation which emphasises the importance of the error area over probable error in evaluating the performance of a cleaning unit.

Jan 1, 1981

Properties of coal which are significant in relation to preparation for carbonization and conversion are reviewed, and existing coal preparation technology which has been used for production of cleaned coal of suitable ash content and petrographic composition for carbonisation, pyrolysis, hydrogenation and similar processes is described. Possibilities for application of this technology to some Australian coal seams is examined briefly. It is concluded that further survey work is required related to the optimization of selective crushing and concentrating operations, with the aim of maximizing production of quality products for carbonisation, etc mainly from Australian seams with only moderate coking characteristics.

Jan 1, 1980

The discussion which followed the publication of my paper by the formert has, I think, enhanced its value. It may therefore be of interest to members of our Australasian Institute, who are not members of the Institution of Mining and Metallurgy, if I give a synopsis of the discussion.My attention was drawn to the fact that my paper did not make clear the extent of the improvement in furnace operations, which followed the use of coke of high quality; this comment applied more particularly to the lead content of slag. My failure to supply comparative figures in regard to the lead content of slag was governed by a condition which, I think, is of interest to metallurgists. As a result of industrial...

Jan 1, 1932

The title of this address was selected before I had an opportunity to consider in detail the matters that I would like to discuss. Accordingly, I chose a very broad subject-so broad indeed that it would be foolhardy for me to attempt to deal with more than a few aspects of it. I do not propose to touch. at all on the developments to date of our mining and metallurgical enterprises, beyond paying a sincere tribute'to the skill and enterprise of those who have established an international reputation for Australian mining and metallurgy. I would rather look ahead and discuss certain factors that will play a decisive part in the future development of our mineral resources. I do this in no dogmatic spirit, and I hope that my remarks may lead to discussions which will stimulate action where it is needed.In recent years my colleagues and I have been forced by circumstances to give consideration to problems in the fields of mining and geology, and in process metallurgy, which lie outside the scope of our own research work. People come to us with metallurgical problems because they know of no more appropriate place to go, and it is distressing to have to inform them that it is nobody's job to offer them advice and assistance. I want to suggest to your Institute that it should press strongly for the provision of properresearch facilities for the mining and metallurgical industries, such as aready exist in most enlightened countries. In such countries, those connected with the development of mineral resources are able to obtain information and advice from Geological Surveys, Mines Departments or Bureaux of Mines, which offer far more comprehensive services than are available in this country.Before discussing specific technical problems of the mining and minerals industries, I shall enunciate certain general principles that I believe should be followed in respect to the technical side of the development of all Australian industries. The problem can, I suggest, be considered in three parts-technical education production, and research. I shall confine my remarks mostly to the research aspect, for it is with this that I am most familiar.For the efficient development of any industry in Australia, it is essential firstly that We should learn what is going on abroad, and secondly that we should simultaneously conduct independent research. In the latter sphere the Governmeht'departments and the private companies' or groups of companies should have complementary functions, the former concentrating on problems common to a number of companies or industries, and the latter on their oWn individual problems. It is essential to the continued existence of Australian industry that both company and govern...

Jan 1, 1944

Since the last occasion on which I spoke to you on this subject there has been a considerable increase in the mechanical ventilation of Western Australian mines.The following table compares the figures for 1939 with those of 1941. The type of fan most commonly used is the limit load fan. On account of its higher mechanical efficiency it has very largely superseded the multivane fan with forward curved blades.Two fans of the propeller type are in use and these have given very satisfactory service. This type of fan also has a high mechanical efficiency particularly at the correct duty for maximum efficiency.The maximum efficiencies obtainable from the various types are, for "multivane" 670/0, for "limit load" 75%, and' for aerovane 7810/0.References to propeller fans with variable pitch have appeared in the technical press, but no detailed d~scription has been issued. The advantages of these fans for mine ventilation are not obvious. An aeroplane is required to operate over a wide range of duties, while the speed of the motor for maximum efficiency is pl'actically constant. In such circumstances the propeller can be adapted to the particular work it has to do by varying the pitch of the blades. In a mine the speed of the fan can be varied to suit.the conditions, and it would appear that variable pitch is not necessary while there is a reasonable range of fans to choose from.The question of the correct position for the fan still comes in for considerable discussion. Exhausting fans at the surface have the support of time and custom, and in many cases this represents the only reasonable arrangement. Such fans should be fitted with an evase, especially in the case of fans with a high outlet velocity such as the aerovane types.It is claimed that there are advantages in having the fan at the surface where it is readily available for inspection and maintenance. Experience has shown that these advantages are more apparent than real. Fans will run for long periods with no attention other than occasional greasing and cleaning, and modern electric motors will run without attention for very long periods.In some instances the expense of a power cable to take current to the fan may be saved by placing it on the surface, but in the majority of cases...

Jan 1, 1941

The area around Big Bell was actively explored and sporadically mined for gold from 1904 onwards. The lease was named Big Bell in 1913. The property became established as a major mining centre with the development of the Big Bell underground mine in 1936. Mining operations commenced in late 1937 and ceased in January 1955, after milling 5.56 million tonnes of ore and producing nearly 21 tonnes of gold. In 1969 Australian Consolidated Minerals Ltd (A.C.M.) acquired the deposit then explored it alone and in joint venture until the current joint venture agreement with a subsidiary of Placer Pacific Limited (PPL) was negotiated in 1984. Following exploration and evaluation of near surface mineralisation, and a reassessment of the remnant pillars underground, the concept of a large open pit in conjunction with an underground mine evolved. The feasibility study was completed in October 1987, and the decision to go ahead was formally announced on 2nd December 1987. Placer Dome Technical Services Ltd were contracted to be the Project Managers, commencing construction on site early in January 1988 and handing the plant over to the operators 13 months later. The capital cost of the project at handover was estimated to be $133 million. The operating team commenced pre-production stripping of the open pit on 1st May 1988. By 31st January 1989 almost 16.0 million tonnes had been stripped and 350,000 tonnes of ore stockpiled.

Jan 1, 1989

By J Youngson

Gold placers can be difficult to locate in areas where tectonic activity and paleogeography have changed significantly since placer formation. Existing placer exploration models are useful in areas that have a relatively simple geological history, identifiable relationships with parent sources, or a history of placer mining. However, exploration becomes increasingly difficult in areas where tectonic activity and sedimentary recycling repeatedly redistribute the gold. Gold placers in the Waitaki River catchment, North Otago, New Zealand have no primary source within the catchment. During the Eocene placer gold was transported by a river ('Buster River') that flowed in a northeast direction from Central Otago toward a coastline at Maerewhenua, North Otago. This river and coastal system was inundated by marine transgression during the middle Tertiary. Since the Miocene its placer deposits have been uplifted and eroded and any links with parent sources have been severed. Changes in paleogeography resulted in local reconcentration and local dilution of placer gold in different areas in the Waitaki catchment. Thin veneers of old Waitaki River gravels (Kurow Gravels), containing gold recycled from the older placers, have been deposited unconformably on strath surfaces cut into Tertiary or older rocks. These gravels along with remnant Eocene fluvial and shallow marine strata provide potential placer exploration targets. Uplift and erosion of non-auriferous rocks in the Waitaki catchment to the west and north of the study area has resulted in considerable dilution of potential placer deposits downstream, especially in areas of gravel aggradation. We present a placer exploration model that is founded on answering fundamental questions pertaining to the paleogeography and geological history of the sediments associated with the placers.

Jan 1, 1999

By Gale D. C, Giles D. E, James Parker A

A zinc-lead-iron sulphide concentrate from McArthur River can be leached at atmospheric pressure in aqueous solutions with HCI, FeCl3, CuCI2, HCl/02 HC1/02/ CuCI2, Cl2, and CI2/CuCI2 to extract >98 per cent zinc, >90 per cent silver, and <15 per cent iron in 1-7 h at 95°. Galena is more reactive than sphalerite and is converted to lead chloride. Except for leaching with HCI, elemental sulphur is the the main by-product of the leach with little or no sulphate ion detected. The rates and products of these reactions are compared. It is recommended that aqueous slurries of the concentrate (50 per cent w/v) are leached at atmospheric pressure with Cl2 in the presence of copper(II) chloride, which accelerates the extraction of zinc. Hydrochloric acid is a by-product which is consumed bYJeaction with fresh concentrate in air at 60°. Copper is subsequently stripped from the leach solution and recycled by reaction with fresh concentrate at 100°. The separation, recovery, and electrolysis of zinc and lead chloride is outlined since this process would produce Cl2 gas which can be recycled and used directly in the leaching stage.

Jan 1, 1976

Significance of the body of iron oxide, which in part overlies as its hanging-wall the rich chalcocite ore-body at Mount Oxide, Queensland, has been variously interpreted by engineers and geologists who have inspected the deposit.Among the interpretations offered is the one that the body represents the residual of an original medium to low grade...

Jan 1, 1939

Amongst representative men directing alluvial mining of erations in Victoria, some difference of opinion exists as to the best system of working the deep leads. The developmental operations of shaft-sinding, extending a reef drive, partially watering and rising up into the wash dirt are practically the same on all fields but subsequent mining is continued either on the Chiltern and Rulberglen or Ballarat systems, the latter being referred to by the Chiltern and Rutherglen miners as the "down country" system. In the former, the leading wash and cross drives are lept from 300 to 500 feet ahead of the reef drive, and in the latter the reverse method keeping the reef drive well ahead of all wash workingsis adopted.In the majority of alluvial mines in the southern and western fields, the initial work of defining the course of the lead is costly, owing to the thick superincumbent layers of hard basalt, to bore which costs from 9/- to 15/· per foot. Unfortunately large sums of money have been wasted in this work, owing to a want of care and knowledge in the selection of bore sites, and improper recording of the strata pierced, thus handicapping alluvial mining and bringing boring operations...

Jan 1, 1902