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By Dunstan N, Valentine C

Gas power was first used on the Sons of Gwalia mine in January 1911, when a twin-cylinder Crossley engine of 167 hp was installed to belt-drive a 112 kw 550-volt ac generator. This engine was connected with a No 8 Crossley up-draught suction gas producer, using mulga charcoal as fuel.A second Crossley engine, of 400 hp direct-coupled to a 550-volt ac generator, was installed in 1912, and operated by a down-draught wood producer.This was followed by a large Kynoch twin tandem four-cylinder engine, rated at 660 hp, sea level, with a rope drive to the crushing and treatment sections of the plant.These engines operated until January 1921, when the plant and power house were destroyed by fire. After the fire, both Kynoch and second Crossley engines were salvaged and reconditioned and they continued to give useful service for some years.

Jan 1, 1932

In the years prior to the outbreak of war in 1939 Australia's production of copper had declined from a peak of about 80,000 tons in 1911-1915 to approximately 25,000 tons in 1939. This production met the need of the slowly growing national requirement and gave an excess for export. However, with the intensification of the war effort in 1942 due to the imminence of a Japanese invasion of this country, or at least a blockade of the sea lanes, it became necessary to expand production of armaments, and consequently the demand for copper increased beyond the capacity of the industry. Importation of copper to Australia during the period 1940-1944 was 131,000 tons.When exploration of the Mount Isa orebody was first being carried out in 1928, No. ID diamond drill disclosed the presence of some copper ore lying outside the limits of the Black Star orebody2, but it was not until 1941-1942 that the development of No. 7 level in the Black Star orebody enabled the existence of a lode of copper ore of economic grade to be established. At the request of the Commonwealth Government of the day a programme of development for copper production was undertaken whilst lead smelting was continued as before the war.A series of flotation tests on up to 1,500 tons of ore at a time, was undertaken and the concentrate so obtained was stockpiled. These tests were conducted, using one section of the lead mill, and demonstrated that a concentrate grade of 22-23% Cu with a recovery of 80-85% might be expected.These recovery figures were afterwards much improved, and 93-95%was obtained before the close of smelting in 1946.

Jan 1, 1953

Information from bores in the LatTobe Valley has been accumulating for over fifty years, and the manual extraction of details has become a limiting factor in their use.Punched card equipment, installed by the State Electricity Commission for accounting purposes, was known to be available for reasonable periods, and it was suggested that this could help in the extraction of data from the voluminous records.Investigation showed that they could be substantially duplicated on cards, with consequent gains on many operations; the cards being regarded as an auxiliary to the existing records.BRIEF DESCRIPTION OF RECORDSAs a bore is drilled a continuous record of the strata is kept, together with notes on the presence of water or any unusual features which the driller may observe.When coal is struck, samples of each ten feet are usually sent for analysis.The location and surface level of each bore is fixed by surveyors, and details of dates and methods of drilling are also kept.Bores are allocated numbers, prefixed by the name of the parish within which they are drilled. Numbers are allocated in conjunction with the Department of Mines, to avoid duplication.Records of strata and analyses are kept in folders, with 100 bore numbers per folder.Standard plans are drawn, showing the locations, bore numbers and surface levels. For each bore they also show the depth and thickness of coal struck, and the total depth drilled.Cross sections are then drawn, connecting the various coal seams, which have been identified by the geologist.

Jan 1, 1960

By Finlayson J. F

The advantages of rapid and accurate analyses are becoming appreciated in many industries today and have resulted in a great increase in the number of samples received by their laboratories. This has caused some firms to consider the installation of one or more of the instruments available for analytical chemistry. In this country there are relatively few people with experience of instrumental methods and it is difficult for a firm considering the installation of such equipment to assess the advantages which instruments may give them, and to decide which instruments, if any, will be of most use to them. The object of this paper is to give a brief survey of instrumental methods in the field of inorganic analysis. Instrumental methods of analysis have numerous advantages when used correctly. They enable extremely rapid analyses to be made in many cases, e.g., analysis of refined lead by purely chemical means takes about two days whereas spectographically the analysis can be completed in approximately one and a half hours. The accuracy ofinstrumental methods, generally between 1 and 5%, is higher than most chemical methods for small percentages of impurities. Furthermore, if the instrument can be calibrated against absolute standards the errors are usually random and not biased to one side of the correct result. The sensitivity is high, enabling in many cases the detection and determination of smaller percentages than can be detected chemically. This high sensitivity enables and, in some cases, requires the use of very small samples, and results in considerable savings in reagents, allowing the analysis of considerably more samples without undue loss...

Jan 1, 1951

By Bhaskara Sarma P V R

Solvent extraction of cobalt from an ammoniacal ammonium sulphate medium was carried out using Di(2-Ethyl Hexyl) phosphoric acid in kerosene as diluent. The effect of ammonium chloride and ammonium sulphate on the extraction efficiency was studied. The extracted species in the ammonium chloride and sulphate systems were CoAz2HA.NH4CI and CoA3.HA.2(NH4)2SO4, respectively. Ammonia scrubbing and cobalt stripping studies were carried out from loaded and ammonia free organic Respectively.

Jan 1, 1992

The use of the heavy media cyclone (HMC) Separation process for the treatment of ores in a particular size range is comparatively new to Australia. The paper describes briefly the principles of HMC operation. Reference is made to early development work, the pilot plant trials and the acceptance of the technique as a mineral dressing process. The Mitchell Cotts pilot plant at Amdel is described briefly and the results of test work on this unit for the processing of a wide variety of ores and ore types are given. Comments are made on the ob- jectives aimed at in the investigation and results are discussed with particular reference to behaviourial differences between ore types. The process is easy to operate, possesses a high capacity-to-unit-size rating and is capable of a high degree of flexibility. Further developments such as specially prepared and graded media for specific applications, automatic media density control and regulation of media consistency by the use of surface ac- tive agents and polymers have increased versa- tility and sensitivity of control to the point where products differing by as little as 0.02 of a specific gravity unit can now be separated with ease.

Jan 1, 1973

Infrastructure is defined as all those parts of a mining development which are not directly concerned with mining and mineral processing. Infrastructure is of significant and growing importance in the overall develop- ment of mines, and the costs could be critical in determining the viability of a project. Prior to_project authorisation, feasibility studies are required, often in considerable detail, to determine costs with adequate reliability. It is necessary that the Engineer should be adequately briefed for carrying out these studies and that good liaison and communication with the Owner be maintained. Methods, costs, order of accuracy, and some special requirements of these studies are discussed. After project authorisation, rapid im- plementation of the proposals is generally desired. A suggested organisation and method for this implementation is presented and dis- cussed. Comments on fees, and particular points in the relationship between Owner and Consulting Engineer are given. Particular reference is made to differences in conditions compared with public works projects. Realistic attitudes of mind towards environmental matters, industrial relations, and contractual relationships are advocated.

Jan 1, 1974

Timestudy analysis of mining operations at North Broken Hill Limited has been carried out by dissecting operations into small elemental components, and accurately timing these elements. Over a wide range of observations, this has enabled standard time values to be calculated for all underground work.The application of the standard values is in calculating performances as a measure of work output and Performance Controls are kept on approximately two-thirds of underground employees. Through the Controls it has been possible to stimulate supervisory action to improve low performance, and to reduce delays and lost time.The values are used to calculate contract" prices, and anomalies in previous prices have been adjusted on work values and not on arbitrary standards. In out-of-the-ordinary circumstances, the request for a timestudy investigation has been made by both operatives and foremen, and the contract set following the timestudy analysis has been to the satisfaction of both parties.The range of values enables contracts to be applied to work which was previously performed on a day basis, resulting in improved performance.A natural corollary of timestudy is the analysis of methods, and in some cases method improvements have been introduced.It is anticipated that further investigations will be made on methods.INTRODUCTIONIn 1953, a Timestudy analysis of mining operations at North Broken Hill Limited was commenced under the guidance of management consultants. Its aim was, to determine standard time values for specific operations, which would provide management with a measure of productivity beyond the existing measures of tons or feet of advance, and also to determine whether increased output was available under existing operating conditions.

Jan 1, 1956

In Munich's peculiar hydrogeological conditions (water bearing sand strata between layers of impermeable clay, silt or marl) are proper functioning groundwater lowering methods of decisive importance for underground construc- tion. Shield tunnelling with compressed air has al- ready proved to be successful. In view of growing application of shotcrete tunnelling it was obvious to consider the use of compressed air even here. After a preliminary research-project the first subway section "shotcrete under compressed air" was 1979 awarded in Munich and since that time five sections have been awarded, respectively completed. On the basis of the experiences meanwhile obtained reports will be given stating the frame conditions in which this new construction method can be applied. The tunnels consist of two shells. The outer ist driven by shotcrete under compressed air. In order to keep the air overpressure low, the groundwater often is previously detensioned or partially lowered. The inner shell of watertight concrete is built under atmosperic pressure.

Jan 1, 1987

Pyrite is a significant gangue sulphide mineral in the Ok Tedi copper ore. Its presence in the flotation concentrate is not entirely desirable since it lowers the grade of the final copper concentrate. Lime depression of the pyrite has been practiced with some success. However, it has been observed that at the pH for pyrite depression a significant amount of the pyrite particles still float. To obtain further insight into the problem this work has been conducted to determine the composition, natural floatability and xanthate flotation behaviour of the various types of pyrite in the ore. The flotation results show that while some types of pyrite float well at high pH values, others are readily depressed. The implications of these results for Ok Tedi flotation plant have been Considered.

Jan 1, 1997

By Medhurst TP, Trueman R

The aim of the paper was to model numerically some aspects of the extraction of coal pillars by split and fendering. A two-dimensional elasto-plastic plane strain model with strain softening and interface mod- elling was used. The model was able to simulate the improvement of conditions experienced in lifting from the fender, when the roof adjacent to the fender has caved. In contrast, when a stook was left, providing support to a span of uncaved roof, the model pre- dicted the fender would suffer considerably more de- formation and strain.

Jan 1, 1992

A statistical investigation of folding at Mount Isa disclosed similar patterns in both the shales and the "silica dolomite" zones. Analysis of these patterns yields 3 groups of folds fully developed north plunging folds, fully developed south plunging folds, and flexuresrepresenting stages of development of folds. Interpretation of results indicates that a regional force from a southerly direction was responsible for the folding.The general pattern of shearing is allied to that of folding, with the exception of bedding-plane shearing. Many shears resulted from continued application of force on folds which ruptured after overthrusting. Other shears resulted from rupture of the more incompetent shale members, without associated folding. The shear pattern is consistent with the theory of a regional force from a southerly direction.INTRODUCTIONThe notes on folding and shearing presented in this paper are part of a current study of the structural geology of Mount Isa.FOLDING 1Measurement of FoldsInvestigation of folding underground involved the measurement of plunge, strike and dip of the axial plane, and the order of magnitude of each fold, together with its location and the rock type. The total number of folds measured was 701, of which 411 occurred in shale areas and 290 within the "silica dolomite" zones. All folds measured are located on main levels, from 7 level to 13 level inclusive. The sections of the mine involved are the Black Star, Black Rock and Racecourse. Detailed investigation of folds on the upper levels (4, 5 and 6) has not yet been done, but observations there suggest...

Jan 1, 1961

During October 1947 an Authority to Prospect was granted by the Minister of Mines to lVIount Isa Mines Limited over an area of approximately 75 sq. miles to the north of Mount Isa.Application for the Authority to Prospect had been made after Zinc Corporation Limited had been granted prospecting rights over two areas, one of 1,265 acres immediately to the north of the Mount Isa Mines leases and the other of 1,960 acres adjoining the south end of Mount Isa Mines leases.METHODSAs a means of providing a cheap map of sufficient accuracy on which to plot geological features, both Mount Isa Mines Limited and Zinc Corporation Limited agreed upon aerial photographs and the two companies shared the cost of an aerial photographic survey by Adastra Airways of 130 sq. miles which covered the prospecting areas held by both companies.The photographs were on a scale of 800 ft. to I in. with 60% overlap on the north-south runs and 25% overlap east-west. A set of alternate prints enlarged to 400 ft. to 1 \in. were obtained for field work. The 400 ft. to 1 in. scale unglossed photographs (size 18 in. x 18 in.) were taken On to the field and rock outcrops, and uncorrelated structures were plotted directly on to them in red crayon pencil. The geological observations were then transferred in the office to a tracing on which accuracy of azimuth and scale was controlled by use of a photo mosaic and ground surveys.

Jan 1, 1953

The paper describes the reasons for developing, specifically in South Africa, dense medium processes to allow baths to operate at low (about 1,35) and high (about 2,0) cut points. Low density processing was developed to meet the demand for low ash coals; high density processing was developed to enable heavily contaminated raw coals, destined to be burned in captive power stations, to be de-shaled without loss of combustibles. The anticipated and actual technical difficulties of operating baths at such density extremes are described, and the results from operating plants outlined.

Jan 1, 1987

By White B

A novel approach is suggested for the solution of planning and development problems in the coal, mining industry. The formation of coal measures depends to a significant extent on sequential geological processes and events which are probably best defined in a "system of processes and responses." The great number of variables in such a system is a characteristic feature of geological environments. Research work over the past two decades, in particular, has successfully established analytical procedures for the identification and definition of relevant and irrelevant variables for mining developments in specific geological situations. Such situations are typifiable within the regional geological setting of coal deposits. Scale gaps can be bridged by reliance on common symmetrical attributes and pervasive geometric features. Depositional processes and their resulting attributes are responsible for the development of mechanically significant rockmass "defects" and anisotropies; such features have to be identified and assessed for the selection of colliery design criteria. It is suggested that the procedural frame- work of systems engineering analysis is a most appropriate tool for the assessment of those geological features that can influence the mechanical behaviour of the "floor-seam-roof" system in "high technology" mining operations of the future. It is anticipated that the overall emphasis of future mining systems will be toward the use of larger scale more highly productive methods and machines, with higher capital outlay but

Jan 1, 1987

South Crofty's ventilation network is large and complex. Of the total exhaust air quantity 40% enters the mine by leakage routes through old workings, this air carries high concentrations of radon gas and results in the mine becoming a classified work place under the Ionising Radiation Regulations 1985. Improvements in the control of the ventilating air and dilution by increased air quantity have reduced the average contamination to aelow-0.2 WL. The major part of the radon originates from ground water inflows and from concentrations of radium within the mine with direct emanation from rock surfaces being negligible. Of 600 kBgs-1 total radon leaving the mine 93% cannot be accounted for from known and accessible sources.

Jan 1, 1988

By Kershaw M. G

At the Risdon plant of the Electrolytic Zinc Company of Australasia Limited, impurities toxic to the electrolytic production of zinc metal, notably arsenic and antimony, have traditionally been coprecipitated when precipitating iron as ferric hydroxide. With the development of a new lead/zinc mine at Elura, New South Wales, it was anticipated that the concentration of impurities, particularly arsenic, in the zinc sulphide concentrates treated at Risdon would increase. This suggested that an increase in the capacity of the iron purification step in the Risdon plant would be required to cope with the higher input of these impurities.Laboratory investigations showed that the additional capacity would be achieved, either by a large increase in the amount of iron used as the "collector" in the process, or by a two-stage process. The latter approach was preferred as a increase in the amount of iron precipitated would lead to much higher operating costs and overloading of the existing equipment.In the two stage procedure, acidic iron bearing solution is added to solution feeding the first stage and most of the arsenic removed from solution when iron is precipitated from solution by neutralisation with limestone. Mter separation of the precipitated solids, acidic iron bearing solution is added to the solution, and remaining arsenic removed almost completely following neutralisation by limestone.This paper describes the laboratory and pilot plant results and the plant modifications required. Abrief account is also given of the operator training and acceptance in the use of the digital control facilities installed in the new plant.The new plant is working well and good solution purity is being maintained despite a substantial increase in the concentration of impurities in the raw materials.

Jan 1, 1990

The importance of the minerals industry to Australia is briefly reviewed and the professional specialists essential for the industry identified. The average first degree graduation numbers in geoscience, mining engineering, metallurgy/materials and chemical engineering are shown and compared with the postgraduate numbers. Demographic trends in population are reviewed and the implications for the required numbers of trained specialists indicated. Short/medium and long-term possible solutions to potential shortages of trained personnel are canvassed.

Jan 1, 1997

Australia, with its fast-growing economy and high standard of a~ living, has a high and rapidly increasing per capita consumption of energyIn total terms, Australia's energy requirements are doubling every 15 years, and among mature Western economies Australia ranks behind only Italy-and Japan in the rate of increase of energy consumption.The use of energy is often accepted as a yardstick of development and on this basis Australia might well congratulate itself on its high energy consumption. However, it is less well recognised that the resources absorbed in the production of energy represent a real cost to the* community, and that just as we strive for industrial efficiency or farm productivity we should strive for economy in the use of energy fuels.Australians spend annually an estimated ú500 million.on all forms of energy, a sum which represents about seven per cent of the Gross National Product. In all, energy production and distribution absorb the employment of more than 100,000 persons. In addition, the annual capital investment by.the oil industry amounts to some E55 millions, by the coal industry about ú12 millions, and by electrical and gas authorities some E108 millions, in total representing more than ten per cent of annual investment in other than private motor cars and housing,

Jan 1, 1962

During the last century Allis-Chalmers has supplied many screens of various types to industry, from revolving screens to the large capacity highly efficient screen available today. The features incorporated over these years in horizontal and inclined screens are varied and numerous and include many innovations such as tri-and bi-sloped screen decks. Today the emphasis is on wide vibrating screens with good "G" value, with large "throw", to achieve high capacity. Larger screens lead the way to treating a somewhat neglected area of mining operations - that of concentrator mine flotation tailings to allow effective transportation and stacking by conveyor belt. The benefits from a cost, water saving and environment view point are discussed in this paper.

Jan 1, 1984