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By Tripathy A. K, Satapathy B. K, Nayak B, Mohanty J. N, Dey D. N

The paper deals with the metallographic tudy of heat treated chromite and chromite-coke composite briquettes. The briquettes, prepared from chromite concentrate of Orissa Mines using molasses-lime, dextrinelime and tamarind seed as binders, were subjected to different temperatures and examined metallographically. The change of phase with temperature was analysed by X-ray diffraction.

Jan 1, 1987

By Walker G. S

A study of the crystalline materials on or near the surface of freshly made or "green" superphosphate granules and mature, "set" superphosphate granules was undertaken using X-ray diffraction, X-ray mapping, scanning electron microscopy and electron probe micro analysis techniques. Calcium sulphate (CaSO4), calcium sulphate hemihydrate (CaSO4 1/2H20), and mono calcium phosphate monohydrate (Ca(H2PO4)2H2O), were the only crystalline species present in the "green" superphosphate.In the set superphosphate however, additional compounds were present, namely complex iron and aluminium phosphates Ca(Fe,AI) H(HPO4hF2)2H2O, (Fe)3(H3O)H8 (PO4)6H2O and calcium sulphate dihydrate (CaSO4.2H2O).The complex phosphates tied up the major part of the Fe and Al in the system and were concentrated on or near the surface of the granule. An intimate mixture of CaSO4.2H2O, and CaSO4, along with the above mentioned complex Fe-AI compounds, crystallize close to the surface of the granule and cause the setting of superphosphate that takes place during storage.

Jan 1, 1980

That electricity is an important and valuable agent, the limit of whose capacity for utilisation is as yet unknown, is a truism; although enormous advances have been made, the possible developments are yet greater. Mining, along with other industries, shares already to a large extent in the practical utilisation of this agent. Electrical engineers have been employed for several years past in developing and applying electricity to all classes of machinery, and for every purpose where power is required and in no instance, that the writer is aware of, has its use been curtailed in favour of any other agency now known, while extensions are continually made. The first modern electric motor was shown at the Vienna Exhibition of 1873, and it was used to work a pump through a mile length of cable but it was not before 1878, that an electric motor was put into daily commercial use by Messrs. Chretian and Felix to work a beet sugar hoist. This early plant effected a saving of 40 % as compared with hand work.In 1879, the first Electric Railway was constructed for the Berlin Exhibition, and in the same year, Mr. T. A. Edison was running an experimental line at Menlo Park. The first electric line opened for the public, was constructed by Siemens and Halske, in 1881, at Lichtenfelde, and was 11 miles in length.

By Belcher C. B

The Groote Eylandt manganese ore deposits contain mainly pyrolusite and cryptomelane with lesser amounts of the manganese minerals lithiophorite, todorokite, psilomelane, and nsutite. The major non-manganese minerals which occur are quartz, kaolinite, and goethite.Determination of the mineralogy relies mainly on x-ray diffraction analysis. Quantitative methods for the determination of pymlusite and cryptomelane in Groote Eylandt manganese ores have been developed, A large amount of isomorphous substitution may occur in the manganese minerals and a number of minor and trace element associations have been noted. A correlation has been established between the potassium and cryptomelane contents for a wide range of ore types. Anomalous calcium, magnesium, and sodium values occur in samples containing todorokite, and barium is associated with psilomelane. Groote Eylandt lithiophorite appears to contain negligible amounts of lithium (<O· 05 per cent).A relationship between the H20+ and the Al203, K20, and Fe203 contents has been estahlished indicating that much of the combined water content is due to the presence of kaolinite and goethite, and cap be removed by beneficiation of the ore.

Jan 1, 1975

This Institute, by nature of its charter, draws on various persons in the mining and metallurgical world of Australasia for its President from year to year, and consequently when the presidential address is given by one of these people the topic. which they generally select is a topic to which they are accustomed and on which they are able to speak with authority.As most of you know, my prime object in life has been concerned with steelmaking, so tonight you can steel yourself to the thought that you are going to be spoken to about steelmaking.Even if that were not the case, and were I not particularly interested in steelmaking, I think it would be appropriate to look at steelmaking in a broad sense on a basis of pure metallurgical interest, because the steel industry is going through as big a revolution today as it went through something over one hundred years ago when Bessemer made a theory become a fact.Bessemer, and as the Americans prefer to think Kelly, separately conceived the idea of blowing cold air through molten pig iron, and, contrary to the then general belief, this did not result in cooling of the metal but succeeded rather in heating it, and in burning out of the rather crude pig iron the impurities which prevented it from becoming a ductile metal.For many years before this, steel had been made in a very small painstaking way by what was known as the crucible process. Benjamin Huntsman is credited with having developed the crucible steel making process to a stage where it could make a reliable and trustworthy product, but he...

Jan 1, 1961

The passage of chloroform vapour in a carrier of oxygen through two nickel sulphide ores heated to 380°C converted the nickel to the water soluble chloride form. In one ore the nickel (2·75 per cent) was presentas violarite ((Ni, Fe)3S4) whereas in the second it was present as pentlandite, ((Fe, Ni)9S8) (4·9 per cent Ni).A similar technique was utilized to convert nickel in nickeliferous laterites (1·6 per cent Ni) into a soluble chloride using town gas instead of oxygen as a carrier.With both techniques greater than 90 per cent extraction was achieved.

Jan 1, 1972

The purpose of this paper is to describe briefly the clean-up procedure adopted at the treatment plant of Paringa Mining & Exploration Co. Ltd. at Kalgoorlie, Western Australia.A clean-up is carried out at the end of each four-weekly period, and all figures subsequently quoted are taken from a summary of the results of the eight periods ending 8th April, 1941.STRAKING AND AMALGAMATIONOf the total gold won 22· 77 per cent. is recovered by straking and amalgamation.The discharges of both the primary and secondary ball mills are pumped over a common set of five ten feet long by three feet wide straking tables, set at an angle of 10 degrees, before passing to the 14 ft. diameter by 30 ft. by 8 ft. Dorr bowl classifier.This classifier is in closed circuit with both of the ball mills, hence the whole of the circulating load of the fine grinding circuit, which approximates to 800 per cent., is required to pass over the straking tables. For convenience in handling, corduroy cloths are used in lengths of 5 feet, and are picked up and replaced by clean cloths at four-hourly intervals. The avaHable straking area provided is, therefore, 900 square feet, or approximately 3·30 square feet per original ton per 24 hours. The density of the pulp passing over the tables is about 54 per cent. solids, the area provided per ton of pulp per 24 hours being approximately o· 2() square feet. Washing of the corduroy cloths is carried out on the day shift only, about 800 lb. of strake concentrate being obtained daily.This concentrate is sluiced from the washing trough on the elevated straking floor to the 4 ft. by 2 ft. diameter amalgamating barrel located in the gold room below.The barrel is of standard design and is rotated at 25 r.p.m. It is charged each day at 4 p.m., and grinding of the strake concentrate at approximately 70 per cent. solids is continued until 8 a.m. the following day. The barrel is then stopped, and the contents generously diluted with water, and after a few minutes rotation some of the slime is carefully poured off through the small discharge hole. This dilution and decantation is repeated until a good deal of the valueless slime has been removed.A further quantity of strake concentrate is then charged to the barrel, which is allowed a further 16 hours grinding period. After again diluting and decanting, approximately 25 lb. of mercury and 15 lb. of lime are added to the charge, which is then given an amalgamation period of 2 hours before cleaning up.By the process of grinding, diluting and removal of slime by decanting...

Jan 1, 1941

By S G. Walters

The minerals industry is facing a productivity and investment crisis. The ‘Millennium Super Cycle’ from 2003–2011 was an unprecedented period of growth and investment resulting in increased throughput and development of lower grade resources to meet demand. During the boom quantity became more important than quality with throughput the key metric. This was accompanied by a general trend of decreasing feed grades across all commodities that was offset with higher production volumes.Current industry perception is that feed grade depletion is an unavoidable consequence of ore deposit geology and mass mining technologies for increasingly mature mining operations. In typical crush-grind-float operations value recovery only takes place at ~1–200 micron particle size during flotation, ie 3–4 orders of magnitude size reduction compared to primary feed. For increasingly low-grade deposits the cost of energy and capital intensity required to process and reject low value material at micron scale drives poor productivity. An alternative is to deploy a range of coarse (~10–100 mm) separation and rejection technologies. Grade Engineering® is an integrated approach to coarse rejection that matches a suite of separation technologies to ore specific characteristics and compares the net value of rejecting low value components in current feed streams to existing mine plans.Coarse rejection can be used on size distributions ranging from run-of-mine (ROM) to semi-autogenous grinding (SAG) discharge. Grade Engineering® is based on five rock based ‘levers’ linked to combinations of screening, sensor-based sorting and heavy media separation. These involve exploitation of preferential grade deportment to specific size fractions during breakage: differential blasting to condition grade by size at bench scale; sensor based sorting at truck and conveyor scale; and differential particle density.Grade Engineering® is being developed and implemented by a consortium of over 30 mining companies, equipment suppliers and research organisations. Emerging results from collaborative site activities demonstrate potential for generating significant value, which can reverse the trend of declining productivity due to feed grade depletion.CITATION:Walters, S G, 2017. Driving productivity by increasing feed quality through application of innovative Grade Engineering® technologies, in Proceedings Tenth International Mining Geology Conference 2017, pp 263–274 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

Exploration work at the southern flank of the Mt. Coffin diapir has encountered three different types of copper ores: copper carbonate, largely malachite; secondary sulphides, mainly chalcocite replacing pyrite; and a primary arsenopyrite-tennantite-tetrahedrite-chalcopyrite association. The secondary copper ore is occasionally stratiform but mainly erratic at the contact between tillites and siltstones of the Tapley Hill formation.There have been two stages of primary mineralization.1. Arsenopyrite, tennantite, and tetrahedrite occur in siderite veins.2. Revival of the diapirism has caused fracturing and local brecciation of the rimrock and subsequently ascending solutions precipitated chalcopyrite. The chalcopyrite also partly replaced arsenopyrite, tennantite, and tetrahedrite.

Jan 1, 1972

In formulating its strategic plan in 1998 the New Zealand Minerals Industry identified two related critical issues facing it. These are, broadly speaking, the issues of access to minerals; and the perception the public has towards the industry and its behaviour towards the environment. This presentation will report on the Industry's response to the public perception issue. The Industry has, through the NZMIA Council, and its Communication and Website Committees, developed and implemented strategies covering: communication through the print media, and through its website www.minerals.co.nz, a long-term educational outreach programme with schools, focussing on the significance of minerals, their contribution to community wellbeing and the negligible long-term environmental effects of the Industry's activities.

Jan 1, 2000

The disasters between 1920 and 1979 in coal mines in Queensland and New South Wales due to underground fire, gas or coal dust explosion or to gas or coal outbursts, have been assessed. The evidence relating to disasters caused by gas explosion points strongly to divergence from safe mining practice as the main cause. There is a need for greater training and education of personnel, closer analysis of gas reports, better monitoring and testing procedures, improved ventilation standards and a policy where safe working practice is actively encouraged. Conditions in the New South Wales occurrences of gas explosion were similar to those at Collinsville, Queensland in that dykes, igneous sills, burnt out coal and faulting were common to all. Information on outbursts indicates that contributing factors were intrusions, depth of cover, fault zones and other geological disturbances, methods of work, pressure and type of gas.

Jan 1, 1982

The district specially referred to in this paper comprises the very gently sloping country extending from the western shores of Port Phillip from the mouth of the Yarra to Footscray along the Bacchus Marsh railway to near that town thence in a southerly direction to the Little River, and along that river to the coast, 1 as may be seen on the accompanying map. Almost the whole of this area is covered by volcanic rocks, consisting of pumerous sheets of basalt, which have been poured out of various volcanic hills in the districts, such as Mts. Atkinson and Cotteril, near Melton; Mt. Maryand Bald Hill, 12 and 16 miles respectively N.W. of Werribee; and vents in different parts of the parishes of Tarneit, Mouyong, Mooradoranook, Pyweitjorrk, and Derrimut. These volcanoes were in an active state of eruption during a late period of the earth's historyprobably the late Pliocenll, or still younger Pleistocene.Occupying a narrow strip of country, for most of the distance along the coast from Williamstown to past the mouth of the Little River, there occur deposits of still younger age, belonging to the Recent period. These lie on the basalt, and extend for distances varying from a few chains to more than a mile back from the beach. They comprise superficial deposits of blown sand, and raised beaches, composed of marine sands...

Jan 1, 1902

At last year's. annual meeting of The Institute, Sir George Fisher, as President, compared it somewhat nostalgically with a meeting of its kind in the 1920s when comment was expressed on the decline of Australianmining and on the lack of new mineral discoveries.I feel that tonight's annual meeting is even more an occasion for nostalgia, for it represents the seventy-fifth anniversary of the founding of The Australasian Institute of Mining and Metallurgy. I hope, therefore, that I may be allowed to retrace some of the circumstances of this Institute's origin and at the same time to look at some of the broader happenings of those 75 years.From this distance in time it is, of course, much easier to get things in perspective and one of the things that compels enormous admiration in looking back over the history of our Institute is to note the qualities of foresight and keen concern for professional standards which moved the pioneers in this Institute. They had no benefit of hindsight to aid them.Just over 75 years ago, a small group of men met in Broken Hill to discus.s the possibilities of forming an association of mining engineers. The moving spirit was Uriah Dudley, our first secretary, manager of the Umberumberka mine at Silverton. The first formal move to form an association of mining engineers came from the Amalgamated Mining Managers Association of Australasia. At the time, this association was a fairly new group, being 5 years old.It had been formed to try to raise the standard of management throughout the industry. Uriah Dudley and our first provisional president, John Howell, held their first talks in 1891 and further meetings at Broken Hill followed. The inaugural meeting, attended by 200 members, was held in Adelaide in April, 1893.

Jan 1, 1968

Kinetic Dependence of Refractory Gold Sulfide Biooxidation Using Different Microorganism Association In this investigation, refractory sulfide concentrate from a deposit located in northern Russia was treated using biohydrometallurgical technology. The objective of this work was to compare the accelerated refractory sulfide concentrate biooxidation abilities of the pure and mixed mesophilic and moderately termophilic acidophiles cultures. Pure culture of Acidithiobacillus ferrooxidans and two associations of the: Acidithiobacillus ferrooxidans + Acidithiobacillus thiooxidans and Acidithiobacillus ferrooxidans + Acidithiobacillus thiooxidans + Leptospirillum + Sulfobacillus were used in this investigation. Results of sulfide concentrate bioleaching were analysed using the enzyme catalysis theory. Different effective kinetics parameters were calculated for Michaelis-Menten equation, such as Michaelis' constant and maximum rate of the enzymatic reaction. It was shown that the increase of microorganisms' species decreased Michaelis' constant. Lower Michaelis' constant characterises increasing bacteria ferment affinity to substrate (treated concentrate). As a result, the rates of sulfide minerals biooxidation have increased. This investigation has demonstrated that cultures of the different microorganism species, including moderately termophilic, allow to enhance different parameters of the biohydrometallurgical technology for the refractory gold sulfide concentrate treatment. We can see that bacterial leaching stage duration decreased and sulfide minerals oxidation increased. When the bioresidues were subjected to the hydrometallurgical stage, which includes aeration and sorption cyanidation, the operation factors were also enhanced. The decrease of aeration duration and the growth of the precious metal extraction by sorption cyanidation was achieved. Cyanide consumption was also reduced. The results of this investigation were used in design of an industrial plant.

Sep 13, 2010

By Lonie W. M

The rapid development of the Australian steel industry over the past twenty years has greatly increased the demand for coking coal from the collieries owned by the Broken Hill Proprietary Co. Ltd. and Australian Iron & Steel Ltd. This in turn has called for an intensive and continuous programme of colliery expansion and new colliery development, along with the reorganization and modernization of existing collieries.This paper presents a general description of the factors involved and the techniques used in planning modern colliery development for the steel industry.PRELIMINARY GEOLOGICAL INVESTIGATIONSIn any colliery development, preliminary geological investigations require a detailed and practical knowledge of the geology and characteristics of the coal-field as a whole. In the early stages of the investigations, probably the most valuable information is obtained from outside the particular area under review, rather than within it, and unless the geology of the coal-field is understood, the projection of the known information into the unknown area cannot be carried out with certainty.Because development of the coal seams from the outcrops has been an apparently simple matter and not subject to the risks involved in deep mine development, the geology of the New South Wales. coal-fields has not received the attention that major mineral resources warrant.Only the most accessible regions of the coal measures have been generally prospected, while the potential areas remain...

Jan 1, 1957

Two events during the past decade have combined to effectively alter the role of the geologist working in Papua New Guinea. The gold boom of the 1980s resulted in a substantial increase in the general awareness at village level of mining companies, gold and landowner issues, and as a consequence of the Bougainville tragedy, landowners are also very much aware of the potential problems of a mining operation in their area. Landowners know they have the power to remove a company from a project area, and government has shown itself to be virtually powerless and unable to help the company effectively. During a considerable proportion of a project's development time, the project geologist is viewed in the eyes of the local community as the 'company'. Good landowner relationships are nurtured over a reasonable time period and the input of the geologist is significant in determining the eventual fate of company-landowner relationships. The initial impressions of the company, gathered by the local community, will have a far reaching impact on the nature and direction of their future exchanges with the company.

Jan 1, 1991

By C McGuire, W Harris, S Arsenault, D Witow, B Rogers

Mining deep orebodies is increasingly becoming the norm as the ‘easy’ orebodies are depleted. Deep ore mining requires significant ventilation and cooling infrastructure to not only meet regulatory requirements for air quality but also to achieve acceptable workplace temperatures with the higher strata rock temperatures and increased auto-compression. At the same time, advances in battery equipment technology are turning the possibility of a battery powered fleet into reality. The switch from a diesel fleet to a battery powered fleet offers several positive opportunities for the design and operation of a deep mine.The potential to reduce ventilation and cooling requirements due to battery powered equipment results in significant cost savings for mine development and infrastructure. Battery powered fleets are not subject to the same dilution requirements associated with diesel fleets thus allowing lower ventilation rates. At the low ventilation volumes possible with a battery powered fleet, surface refrigeration plants are limited with respect to the amount of cooling that can be delivered to the workface. Considerations for calculating the optimum air flow and cooling requirements are presented. Considerations for locating the refrigeration plant are also discussed. This paper presents these opportunities and considerations; including a case study comparing the ventilation and cooling system design with a diesel fleet versus battery fleet for a planned mine in Northern Ontario, Canada.CITATION:Harris, W, Arsenault, S, McGuire, C, Rogers, B and Witow, D, 2017. Diesel to electric – creating a positive paradigm in underground ventilation and cooling, in Proceedings Australian Mine Vent Conference 2017, pp 169–174 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

The coalmining industry in most countries has, at various times, suddenly been confronted with a decrease in demand for coal. Readjustments made to reduce productive capacity to match the reduced demand for coal have often resulted in hardship to mineworkers, loss of capital investment to mineowners and loss of coal reserves. The consequences of the methods of readjustment adopted in the past have contributed to the low esteem in which coalmining has come to be regarded by a large section of the gel).eral public in many countries.Four sections of the coalmining industry, representing different periods of time, different countries, and different methods of industrial organisation have been examined:Great Britain and the U.S.A. during the inter war years, the post war European Coal and Steel Community, and post war Great Britain under the National Coal Board. An assessment has been made of the methods adopted in each case to reduce productive capacity to match a reduced demand for coal. Finally the fundamentals of the problem-as it affects the coalmining industry of any country-are considered, and possible solutions put forward.During the 1950's, surplus productive capacity was a problem in many coalmining countries, including Australia and New Zealand. As a rule no techniques are developed beforehand to solve problems introduced by a sudden decrease in demand for coal. The situation is usually tackled by a series of short term decisions based on expediency, which often in the long run only aggravate the problem.

Jan 1, 1961

By McKenzie A. M

The Corridor ore body is so named because it occurs in an east-west zone or corridor of schist bounded on the north by the siliceous conglomerates of Mount Lyell, and on the south by similar conglomerates of the Tharsis ridge (Fig. 1). It was discovered after the geophysical prospecting methods described below had defined a target zone for diamond drilling.Since the proving of copper mineralisation by drilling, the corridor orebody has served the vital function of a convenient known target body for the orientation of more recently developed geophysical methods. Traversing of the orebody by these new methods has provided experience for the evaluation of anomalies elsewhere.Some of the methods applied had not been used in Australia before, and were introduced to the west coast of Tasmania through the undertaking there of modern regional exploration programmes. The authors feel that the information gained could be of assistance to others engaged in geophysical prospecting.HISTORY OF DISCOVERYProspecting in the Mount Lyell district has been more or less continuous since 1881. The first geological report was published by Thureau (1886).In 1934, Blazey and Douglas (1934-38) commenced geophysical surveys at Mt. Lyell using the equipotential method.They obtained anomalous indications in several discrete zones and actually detected the south-east half of the corridor orebody but their work never became the basis for...

Jan 1, 1961

Studies of the Main Seam in the Rapahoe Sector of Greymouth Coalfield have shown that the proportions of palynomorphs and palynomorph groups vary vertically within the seam, but remain laterally consistent. Subsequent examinations of other seams in the Rapahoe Sector have demonstrated that the changes in palynomorph proportions observed in the Main Seam are specific to that seam, effectively providing a seam 'fingerprint'. Such a characteristic signature may be used to identify the Main Seam where faulting or seam splitting confuses seam correlation between drillhole intersections. Palynomorph assemblages are derived from the original plants which formed the peat mire, and yield information on mire conditions such as climate, mineral matter input and chemistry. These depositional factors influence coal properties such as mineral content, volatile matter yields and coal breakability. Palynological data can therefore assist in development of depositional lTIodels for prediction of coal quality variations. Several other, thiner seams in the Rapahoe Sector have been demonstrated to also contain recognisable palynomorph assemblages, suggesting that other seams may also possess distinct palynomorph abundance profiles.

Jan 1, 1996