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Local conditions at Hatches Creek are described, together with the mineralogy, mining and treatment of tungsten ores, with particular reference to procedures adopted by Pimer Mines, N.L.The Hatches Creek tungsten field covers an area of about 20 square miles in: Central Australia; 285 miles' N.E. of Alice Springs. Access is by rail to Alice Springs, then by 200 miles of bitumen highway to Barlo Creek and 8,5, miles of bush track to the field. Passengers can also reach the mines by... A semi-desert climate prevails Rain; generally in the form of thunderstorms falls in the summer months: December to March. Average annual rainfall is approximately 15 inches but there is great variation from year to year, occasional droughts being followed by torrential downpours. Vegetation is sparse except in the wide creek beds. Surface water occurs in rock holes some of which, spaced miles apart, carry permanent water...

Jan 1, 1955

By Lavers G

Factors governing the dissolution of nickel and iron in pentlandite and pyrrhotite concentrates from Mt. Windarra were studied for aqueous solutions at normal temperatures and pressures. The effects of dissolved dioxygen, carbon dioxide, hydrogen ions, and chloride ions are described. The direct reaction of aerated water wiili pyrrhotite is much faster than with pentlandite, and reaction rates are proportional to the dissolved dioxygen concentration. In both cases divalent metal sulphates are produced initially. The subsequent oxidation of iron(II) to iron(III) and its oxolation produces acid solutions which rapidly attack both minerals. The presence of carbon dioxide or chloride ion has little effect on these rates.

Jan 1, 1976

By P Fullagar

Automated multi-sensor core loggers (MSCL) measure petrophysical properties of diamond drill cores, including gamma density, P-wave velocity, electrical conductivity and magnetic susceptibility. A Geotek MSCL system has been used to record petrophysical data on archival drill core from Cadia East Au-Cu porphyry deposit, New South Wales, Australia, for correlation with metallurgical parameters. P-wave modulus, calculated from density and P-wave velocity, exhibits a correlation with small-scale crushability (A*b) test results, and hence offers a means for æcontinuousÆ characterisation of ore crushability at Cadia East. Magnetic susceptibility has proved to be a good indicator of alteration styles, and is a possible indicator of crushability.

Jan 1, 2009

By Fookes R. A, Gardner K. J, Gravitis V. L, Watt J. S, Steffner E. J

Two radioisotope techniques suitable for the rapid laboratory determination of the ash content of coal have been tested ou unwashed coal samples from four Australian coal seams. In one techniqne, measurements of backscattered 238Pu L X-rays and iron K X-rays from finely ground coal samples have been combined to determine ash content in uuwashed coals to ±0.5 weight per ce111 ash (ls) for three seams and 0.9 weight per cent ash for the fourth.The second technique, which involves measurements of the transmission by the coal of narrow beams of 241Am 60 keV and 123Ba 356 keV ? rays, requires less sample preparat ion. The ash was determined to within the range of 0.8 to 2.6 weight per cent for the four seams (unwashed coal). For washed coals, errors are expected to be < ±0.5 weight per cent ash.

Jan 1, 1982

Flue dust from the sintering of base metal sulphides was leached to remove cadmium and arsenic. Leach liquor contained cadmium, zinc and small amounts of other base metals as chlorides. Results are reported of the use of a cation exchange resin Zeocarb 225 to separate the base metals from the arsenic. The resin was eluted with sodium chloride or sulphate to give a solution of relatively concentrated cadmium suitable for recovery by zinc cementation. The limited solubility of sodium sulphate presented some practical problems which were investigated. Another problem was the precipitation of lead sulphate in the resin during elution.INTRODUCTIONWhen lead-zinc sulphides are sintered prior to smelting, the gases passing to the flue are mainly uncondensable but contain a certain proportion of sublimates and dust particles which deposit in the flue or are carried, after condensation in the gas stream, to some form of dust extraction equipment.The recovered dust is a complex mixture of base metal sulphates, sulphites, sulphides, chlorides and oxides, the composition depending on the original concentrates. A large proportion of the cadmium and some of the arsenic originally in the concentrates finds its way to this flue dust, the treatment of which can be a convenient means of removing these elements and controlling their concentrations in the main lead-zinc smelter circuit. However, disposing of this material represents an appreciable waste of base metals as well as a serious toxicity hazard.Sulphide Corporation Pty. Ltd. was faced with this problem in planning the flow sheet of the new lead-zinc smelter at Cockle Creek, N.S.W. From a test run carried out on a pilot plant at Avonmouth, U.K., using a mixture of lead and zinc concentrates, a sample of dust was obtained for...

Jan 1, 1960

The dynamic response of holdup in a continuous ball mill has a direct influence on the rate function of grinding kinetics and is useful for predicting the variation in the size distribution of the finished product with time.A model was proposed involving three interacting, completely mixed chambers and this was used to derive analytically the transfer function of the system, from which the unit impulse response and the unit step response of the holdup with feed rate were obtained.The theory was confirmed by comparing it with previously published experimental data for the residence time distribution of particles passing through a ball mill.

Jan 1, 1975

By Cocquio D. S, Bauchau C

In the course of an integrated airborne survey in 1975, a uranium-molybdenum deposit was discovered by Minatome Australia Pty Limited in North Queensland, Australia, approximately 70 km by road west of Townsville.The mineralization occurs in a welded tuff unit within the Carboniferous St James Vokanics. It is structurally controlled by a complex of subvertical east-west fractures and is exposed over a strike length of 350 m. Drilling has traced a further 150 m extension underneath a barren capping consisting of a thick pile of vokano-sediments. The maximum width of the orebody is 150 m, and its vertical thickness is approximately 100 m.The primary ore minerals are coffinite, pitchblende and molybdenite, accompanied by various alteration products (particularly uranium molybdates).The vein-type mineralization is considered epigenetic.A comprehensive program of surface drilling and underground exploration is in progress to establish the uranium and molybdenum reserves.

Jan 1, 1980

By Kumar A, Mishra N. C

For each tonne of chromite ore mined in Sukinda, approximately ten tonnes of fine overburden material is generated. The overburden typically contains about 30 - 60 per cent Fe2O3, 0.3 - 1.1 per cent Ni, four to nine per cent Cr2O3 and 0.04 - 0.2 per cent cobalt and is being discarded leading to loss of valuable metals and creating environmental pollution. In order to take the advantage of presence of iron, nickel and chromium, the present studies advocate the utilisation of nickel lateritic chromite overburden for production of Ni bearing pig iron through blast furnace extracting maximum iron and nickel from the chromite overburden. The present paper deals mainly with the beneficiation of chromite overburden, sintering characteristics and thermodynamic studies. The beneficiation study shows that a beneficiated concentrate having Fe - 50 per cent and Ni -- 1.1 per cent can be achieved from chromite overburden having Fe - 30 per cent and Ni -- 0.7 per cent. Sintering studies have been carried out with bed height of 300 and 450 mm at a suction of 600 and 900 WG respectively. The results reveal that good quality sinter can be produced from chromite overburden concentrate with a basicity of about 1.0 and coke breeze consumption rate about 16 per cent. In all the experiments, Tumbler Index, Abrasion Index and Shatter Index was found to be in the range of 65 - 70, 4.5 - 5.5 and 85 - 90 respectively. The other parameters namely softening temperature, melt down temperature, reduction degradation test and relative reducibility have also been determined. A thermodynamic analysis has also been carried out to make a technological assessment of the process for the production of alloyed pig iron from chromite overburden in blast furnace which shows that it is possible to produce nickel bearing pig iron in blast furnace using the sinter up to 80 per cent. Techno-economic analysis reveals that this route will yield a substantial profit even after accounting for cost of beneficiation, extra coke, raw materials and extra slag produced.

Jan 1, 1999

In this paper, the scientific bases of creation of simulation modelling systems of excavator-truck-conveyor complex work are represented. During the simulation modelling process of big mining and transport systems work the strict and full account of an order and sequence of all operations of simulated process is carried out. Step-by-step fixing of mining and transport system elements condition - excavators in loading and unloading points, trucks, road section, unloading points in storage bin, crushers and conveyors is conducted. Work and idle time of system elements are considered. During modelling process the information characterising system work as a whole is collected. It allows us to establish qualitative and quantitative influence of each system element on the final results of its functioning and provides to estimate rationality of a particular organisation variant of mining and transport equipment interaction from technological positions. Simulation results are: economic and technological indicators of mining and transport complex functioning of the period for each subsystem, as well as on the road, the points of loading, unloading and reloading.

Dec 6, 2010

On the Kinetics and Equilibrium Models for Biosorption of Ni(II) onto a Gram-Positive Bacteria Strain, Rhodococcus opacus, for Environmental Applications The aim of this fundamental study was to evaluate the biosorption of Ni(II) from aqueous solution streams onto a Rhodococcus opacus strain through kinetics and equilibrium isotherms studies. The biosorption of nickel achieved its highest value in a pH around 5. The experimental data evaluation was carried out focusing three two-parameter models, as: Langmuir, Freundlich, Dubinin - Radushkevich. In order to determine the best isotherm fit, three error analysis methods were used to assess the data: correlation coefficient (R2), residual root mean square error (RMSE) and Chi-square test. The error analysis established that the Freundlich model fits better the nickel biosorption data. Maximum uptake capacity of nickel reached a value around 7.63 mg.g-1 for R. opacus. The biosorption rate was fast and achieved a removal of around 79 per cent of Ni(II) in the first 5 minutes at room temperature (25 ¦ 2¦C). The experimental kinetics data was evaluated considering two models (pseudo-second order and pseudo-first order). The error analysis established that the pseudo-second order model better fits the data.

Sep 13, 2010

A comparison is made between elementary block estimation techniques and the optimal methods of geostatistics using data from an Australian deposit. Considerable improvement in the estimates are obtained by using the optimal technique in this case.

Jan 1, 1975

A field method combining solvent extraction and paper partition chromatography permits a simple and rapid semiquantitative estimation of gold in siliceous, argillaceous and sulphide ores. The method will facilitate the eyaluation of prospect samples in which the gold is too fine for separation by panning.Ethyl alcohol-hydrobromic acid mixtures are suitable for chromatographic development of the gold complex, and give clear reproducible definition of the gold zone. Substitution of commercial "methylated spirits" for the ethyl alcohol gives equally good definition, improving the potential of the method for field use.A batch of six samples in the range of 0·5 to 5·0 dwt/ton can be completed in two hours. The range may be extended by simple modification to higher or lower values.INTRODUCTIONIn a chromatographic method described previously (Lever 1958, Nevill and Lever 1959), gold from a standard volume of ore clamped between -plate glass was extracted by aqua regia on to the paper. After cautious drying the chromatogram was developed by an ethyl acetate-nitric acid-water mixture and gold was identified by spraying with stannous chloride solution. Sensitivity of the method in the low range was poor. The brown line obtained in the 1-3 dw/j ton range, caused by movement of gold in the reduced form, was not considered to be a satisfactory confirmation of the presence of gold. It was felt that the method would be improved by using a more elegant extraction and applying developing conditions which would produce a well defined purple line at all gold values. Iron was a limiting factor, and a method of eliminating its interference was needed.The method now developed overcomes these shortcomings, and gives a reliable result with a purple line for assay values of 0·5 dwtjton and over. Gold is dissolved from an...

Jan 1, 1964

In dealing with the pulverization and treatment of auriferous ores, it may be stated that there is not one system of treatment applicable to all classes. In the southern portion of New Zealand the ores generally contain free gold, with scarcely any impurity that is, it is found in an almost pure state, without any alloy, and its dissemination amongst the matrix is generally in tolerably coarse particles. The only difficulties the mill man has to contend with, are the economical concentration of pyrites, which in some of the lodes are rich in gold, and the extraction of the gold the pyrites contain. In some of the lodes there is what may be termed float gold, that is, the particles of the precious metal are so finely divided that it passes over the quicksilver tables, and, unless there are other appliances for saving it, this class of gold is entirely lost.Indeed it is only within the last five years that any attention has been given, in the southern portion of the colony, to saving the fine gold that has passed the amalgamating tables. In the North Island the ores are very complex there are scarcely two mines, although they may be adjoining each other, where the bullion is of the same character. On every field the gold is alloyed with silver', and in combination with other metals and mineral substances, such as copper, zinc, antimony, galenfl, iron, sulphur, arsenic, etc., and, in some instaaces, cinnabar, as in the case of the Champion lode at Tui Creek, Te Aroha. Ores of this class are extremly difficult to treat satisfactorily.

Jan 1, 1903

Variations in delay timing can have a marked influence on blasting effectiveness and, hence, on total production costs. In single-row bench blasts, delay firing is invariably more effective than simultaneous initiation. In single-row delayed blasts, there is an optimum inter-hole delay above and below which inferior blasting results are obtained. This optimum delay is equal to the time required for each charge to just effectively detach its quota of the burden. The inter-hole delay should seldom be less than 4 ms.m-l of burden.In multi-row blasts in which holes in a given effective row are fired on the same delay, the entire burden on any effective row should be detached from the rock mass just before charges in the next effeotive row detonate. Delays shorter than this give inferior blasting results and an increased likelihood of environmental and slope stability problems. If the inter-row delay is too long, cut-offs can occur, especially where the delay unit is located outside the blasthole. For a surface delay system, the optimum inter-row delay usually varies between 4 ms.m-l and 8 ms.m-l of effective burden. The number of rows that can be fired effectively with surface delay systems (in a single blast) is limited by the threat of cut-offs. Greater interrow delays and a larger number of rows per blast can be fired to advantage with down-the-hole delay systems.There are practical limits to the timing accuracy of all available delay systems. The existence of delay time variability should be recognized and duly considered in the design of blasts.The relationship between delay timing and blasting vibrations is not discussed.

Jan 1, 1977

By M Pizey, M Kingsbury

Since 1950 Stockton Open Cast Mine has excavated over 60 million tonnes of Brunner Coal Measures overburden sandstones and mudstones. The current operator, Solid Energy New Zealand, recognises that acidic drainage from this overburden and from historic underground mines has led to depressed pH levels and elevated levels of metals in streams draining the Stockton Plateau. These streams report to the Ngakawau River. To quantify the effects of mine site acid drainage remediation/mitigation on the lower Ngakawau River water quality, a catchment hydrogeochemical model has been field calibrated and ecotoxicology tests have been undertaken. The hydrogeochemical model indicates that pre-mining and present pH values in the lower Ngakawau River are similar but present aluminium and iron concentrations are elevated. Ecotoxicology tests have semi-quantified the critical metal concentrations and interim water quality targets to achieve ecological recovery are presented. Analyses of long-term total suspended solids (TSS) and turbidity monitoring in the lower Ngakawau River and St Patrick's Stream indicate that TSS of 120 mg/L and turbidity of 20 NTU are exceeded for <20% per cent of the time. Hence, specific criteria to protect migratory native fish from turbid water are currently met in the Ngakawau River and St Patrick's Stream.

Jan 1, 2003

Ammonium nitrate-fuel oil (ANFO) explosives are unstable in hot, reactive sulphide-rich ground at Mount Isa. Under certain conditions associated with background heat, moisture, and chemical impurities from natural oxidation, ANFO composites in contact with hot ground disproportionate and the ammonium nitrate can undergo rapid exothermic reactions with sulphide.Reactions can occur in confined charges from prolonged contact with reactive sulphides, or by contamination with sulphide in loading. Partial interaction can result in misfires or premature detonation. Spilt, scattered and unpropagated explosive will undergo further reaction in sulphide-rich environments. ANFO-sulphide interaction is invariably exothermic and causes an irreversible chemical transformation of the ore.The heat generated during reaction may be dissipated, heating the environment, or rapidly accumulated to yield hot spots or areas in excess of 400°C. These can result in forced ignition of bulk sulphide and sustained combustion.Thermal analysis was used to define the critical conditions for ANFO-sulphide interaction and sulphide combustion.The occurrence of incandescent ore is attributed to the thermal interaction between exothermic hydrolysis oxidation, ANFO-sulphide, and combustion processes.Chemical agents and control methods have been developed to prevent ANFO-induced oxidation and combustion.

Jan 1, 1968

By Moskovits E. E

Spodumene was recovered from pegmatite by flotation in laboratory and pilot-plant tests using an anionic collector emulsion. A similar process applied to beryl pegmatite gave encouraging results.INTRODUCTIONOver the past two decades lithium and beryllium have aroused increasing interest in the metallurgical world. Both these light metals have potential uses in nuclear shielding and cooling and in lightweight alloys, and there is a growing demand for lithium chemicals for ceramics, air conditioning and lubricants. The use, technology and history of lithium has been surveyed by Schreck (1961).For many years, the only commercial production of lithium and beryllium was from pegmatite deposits amenable to hand cobbing. The most important minerals of these ores are spodumene and beryl, which are respectively lithium aluminium silicate and beryllium aluminium silicate. Norman and Gieseke (1940) investigated the treatment of lithium ores by froth flotation. The process of flotation of the pegmatite constituents away from the spodumene was applied commercially in 1951, and the operation has been described by Goter, Rainey and Hudspeth (1953). Subsequently, the flotation of the spodumene from the pegmatite was studied by Munson and Clark (1955) and Browning and McVay (1961), and this method has superceded the reverse flotation process commercially. Muskett, Tasker and Hobson (1962), in applying the method of Browning and McVay in pilot-scale tests, reported difficulty because of activation of quartz and felspar by iron salts introduced during milling of the ore.The flotation of beryl, reported by Ashton and Weir...

Jan 1, 1963

Mining education has received almost continuous discussion since its inception and most people engaged in the mining industry and in mining education feel at some time the urge and necessity to express their views. This paper is not a comprehensive survey of past and present practices and accepted principles, but a personal opinion of the form mining education should take at university level. It is expressed because of a dissatisfaction with the existing courses offered to students. It is hoped to provoke discussionand bring forth guidance to those engaged in mining education. After all, students spend four or five years at a university and it is desirable that the graduate should be something more than just those many years older at the end of his course.POST GRADUATE EMPLOYMENTThe first problem confronting the university should, be to discover what the mining industry wants and expects or graduates. This must influence the university course and yet universities have done little to seek this information, and if suggestions have been offered by industry; universities appear to have made little use of them. University mining curricula are basically what they were 50, 100 and even 200 years ago. (See Appendix.) Whether this reflects the unchanging problems of mining the wisdom of early professors, the conservatism of subsequent professors or inability to apprectate necessity for changes, is debatable.Unfortunately there is no uniformity in the type of employment offered to new graduates: Some mining...

Jan 1, 1959

Beneficiation of Iron Ore - Washing with Surface-Active Agent The stability of the dispersed phase in 10 wt per cent slurry of iron ore slime and fines was studied at pH 5 and different concentrations of surface-active agents. The behaviour of the dispersed phase of iron ore slime and fines is different for different surface-active agents. The improvement of iron value of slime and fines in the presence of surface-active agent is best realized at pH 8, where the Al2O3/Fe and Al2O3/SiO2 ratios in the concentrates are appreciably reduced. The polar functional group like -COO- interacts with hematite surfaces and forms outer- and inner-sphere surface complexes depending on the suspension pH and adsorbate.

Sep 13, 2010

By Y Chen, G Xu, B Albijanic

High concentrations of airborne coal particles is the main reason leading to health and safety hazards in underground coalmines. Water spray is one of the effective methods to suppress coal particles in mine sites, but the use of plain water is not effective enough to capture coal particles. By adding surfactants, coal wettability can be improved which will increase the coal dust suppression efficiency. In this study, a modified sink test was employed to evaluate coal wettability in the presence of two anionic surfactants: sodium dodecyl sulfate (SDS) and sodium dodecyl benzene sulfonate (SDBS). Sink rates were calculated by measuring sink weight over test time. Different surfactant concentrations (0.01 per cent, 0.05 per cent, 0.1 per cent, 0.2 per cent and 0.4 per cent) and two types of water (tap water and deionised water) were selected to investigate coal wettability over three size ranges (0–38, 53–75 and 75–90 µm). The results show that both SDS and SDBS surfactants can lower the water surface tension and improve coal wetting performance. Sink rates increased as the surfactant concentration increased, and surfactant solutions prepared by tap water performed better than deionised water in enhancing coal wettability. Also, coal wettability varied for different coal particle sizes; the smaller coal particles were, the worse the wettability they possessed.CITATION:Chen, Y, Xu, G, Wang, R and Albijanic, B, 2017. Study on coal wettability for dust suppression in the presence of surfactants by sink test, in Proceedings Australian Mine Vent Conference 2017, pp 105–110 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017