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Size Separation Pretreatment and Alumina Recovery from Bayer Red Mud

Sep 13, 2010

Ilmenite production in Western Australia commenced in 1956. There are now five producers, all in the Bunbury-Capel district, and current total production capacity is about 450,000 t.p.a.The deposits occur near the surface and average between 10 and 50 per cent heavy mineral. About 70-85 per cent of the heavy mineral is ilmenite. Other heavy minerals present include leucoxene, zircon, rutile, monazite, and garnet. The ilmenite contains 52-60 per cent Ti02. and is very low in chromium (0·03-0·04 per cent CrS03)Mining is done by sluicing, drag line excavation, or dredging. Primary concentration of the heavy minerals is achieved by spirals, revolving cones, or Reichert cones. After drying and screening, ilmenite is separated from the heavy mineral concentrate by various types of magnetic separator.Separate leucoxene, zircon, rutile, and monazite concentrates are also produced. Each plant uses a different technique and the processes used include chemical attritioning, screen plate electrostatic separation, high tension rolls, air tables, and dry launders.INTRODUCTIONThe treatment of beach sands in the Bunbury/Capel area for the extraction of ilmenite is a very recent development in the mining industry in Western Australia. Nevertheless, since the commencement of production in 1956, ilmenite has become the sixth most important mineral produced (Table 1).The increasing world recognition of Western Australia as a major producer of ilmenite (Table 2) is due primarily to the low chromic bxide content of the mineral (0' 03-0' 04 per cent Cr203), combined with a medium to high titanium dioxide content (54-60 per cent Ti02), supported by large reserves, a stable government, and close access to good shipping facilities. Ilmenite is. produced from these deposits at low cost which enables the industry to compete on world markets despite high rates for sea freights because of the distance from major markets.

Jan 1, 1965

With the exhaustion of orebodies close to the main haulage shaft of the Emperor mine, an increased rate of development, aimed at earlier investigation of values disclosed by exploration drill holes has been attained with an overall reduction in unit costs.This paper describes the techniques used in rates of advance up to and exceeding 1,000 ft per 28-day period.

Jan 1, 1966

The term slag has been used to define a wide variety of material including mine spoil and slag produced at steel plants. The present paper is concerned only with the non-metallic alumino-silicates developed simultaneously with iron in blast furnaces.The control of iron quality by slag has long been appreciated but here aspects of slag control based on concurrent iron production are indicated. Consideration is given to the basic composition of slags relative to the type of allotrope required. Up to a point, the plant conditions, under which a particular slag type is processed, have some effect, but these conditions only widen the range of a given allotrope.They do not convert one slag type into another. The nature of the slag types and experiments with additives to convert one slag type into another are discussed.The various uses for allotropes of blast furnace slag are considered.Their use in air cooled slag, foamed slag, slag wool, cements, soil stabilization, glass bottles, and building bricks and blocks, is explored in some detail.INTRODUCTIONWithin recent memory, blast furnace practice has been solely concerned with the production of iron. The slag make at this time had not reached embarrassing proportions. In Britain, unlike Germany, no legislation existed to prevent the growth of unsightly slag banks. Generally slag found limited use as fill and road material in the immediate plant vicinity. This is broadly the case in Australia today. In Europe and America, where the slag make is of the order of several million tons annually, the room problem and the cost of dumping slag has stimulated commercial and scientific research on the disposal problem. Currently, most iron plants in Europe can profitably dispose of at least 95 per cent of their slag make.

Jan 1, 1964

By Edmonds W, Jeffcoat R

The completion of the first two open hearth furnaces in the new No. 2 open hearth plant at Port Kembla will increase Australian production of steel by 350,000 tons of ingots per annum.The paper gives an outline of the essential features of open hearth design and auxiliary equipment required to operate the two modern open hearth furnaces at present being installed.INTRODUCTIONThe increasing demand for steel required by Australian secondary industries led to the decision to construct and operate No. 2 open hearth plant at Port Kembla. Two basic open hearth furnaces of the most modern design are under construction and it is anticipated that these units will be commissi.oned in September 1956. Australian steel capacity will thereby be increased by approximately 350,000 tons of ingots per annum.PLANT LAY-OUT AND CONSTRUCTIONIn the design and lay-out of this plant the emphasis has been on efficient material handling with simplicity of design and operation. Overseas methods were studied and these studies, together with experience gained at Newcastle and Port Kembla open hearth shops, enabled this plant to be built to a standard which compares favourably with any other in the industry.Initially two furnaces, each of 2,75 tons capacity, have been built, but provision has been made in. the design and lay-out to enable expansion to six furnaces.The location of the new plant in relation to the existing units will be noted in Fig. 5. It is one of the first units to be built in an area which will dovetail into a pattern for...

Jan 1, 1957

Following extensive trials on a 100 000 tpa Research and Development facility at Kwinana, Western Australia, Hismelt Corporation (wholly owned by Rio Tinto) are confident of the future commercial success of this technology. The Hlsmelt process uses iron ore fines and non-coking coals to produce molten pig iron suitable for feeding to BOF and EAF steelmaking vessels. The unique process configuration combines direct injection of raw materials into the molten iron bath, high rates of metal and slag mixing, and effective post-combustion of the bath gases to achieve efficient coal utilisation. This is the key to the strong economic performance of the process.

Jan 1, 1999

A process was developed, on a laboratory scale, for the removal of iron oxides from Weipa pisolitic bauxite. The technique involves the chemical reduction ofthe iron oxides by carbon, followed by selective removal of the iron species by acid leaching or chlorination.To remove more than 90 per cent of the iron it is necessary to reduce the iron oxides substantially to iron metal by heating the bauxite, pre-calcined at 650-800°C, with reactive carbon at 1040-1100°C. Reduction proceeds via the intermediate formation of hercynite (FeO.Al2O3) and difficulties have been encountered in reducing hercynite formed under less favourable reduction conditions.Following reduction, efficient selective removal of iron species is readily effected by acid leaching using dilute hydrochloric acid at 100°C, or chlorination at 500-750°C using Cl2, Cl2/N2, or Cl2/N2/CO mixtures.After removal of unreacted carbon, the final products contain 0·5-1.0 per cent Fe203 and 87-92 per cent Al203.

Jan 1, 1971

By Freeman C, Dingley W

Addition of sodium nitrite-borax, sodium hydroxide, sodIUm carbonate, lime, or sodium silicate reduced wear of forged steel balls and cast iron slugs in wet grinding a complex zinc-lead-copper sulphide ore in laboratory ball mills. Maximum wear reductions were 27 per cent (forged steel balls) and 33 per cent (cast iron slugs) with sodium hydroxide and nitrite-borax additives respectively.Potential measurements of balls and slugs during grinding, and analysis of the data in terms of corrosion theory demonstrated that corrosive wear had been reduced or prevented by these additives. Actual per cent wear reductions were not equated to the rate of corrosive wear because of the undefined interdependence between abrasion and corrosion in wear processes. The investigation verifies that in laboratory ball mills corrosion is significant in the wear of grinding media and wear can be reduced by corrosion inhibition and pH adjustment.

Jan 1, 1978

By Williams K. C

This paper presents a brief account of the plant which has been developed at Port Pirie to recover, by vacuum distillation, the greater part of the zinc content of desilverized lead. The present plant is an experimental unit, which is run in conjunction with the normal refinery practice, but can be cut out of the circuit. It will shortly be dismantled and duplicate units will be built on the sites chosen for the final plant installation.The unit described here has treated flows of 16 to 37 tons per hour of desilverized lead, to recover 90 to 95 per cent of the zinc contained in it. It is not intended here to detail all aspects of the vacuum dezincing operation, nor the developments which precededthe adoption of this design. The essential features of the present plant will be described and, where these are peculiar to the present experimental location, the intended alteration for the final plant will also be mentioned. OUTLINE OF PLANT AND PROCESSLead issues from the continuous desilverizing kettle at about 350° C. containing about 0·57 per cent Zn. It is conveyed by a tiled launder to the preheater, where it is heated to 580-620° C.Hot lead from the preheater enters the vacuum vessel via a barometric leg. From a reservoir holding about 19 tons of lead it falls by gravity in a thin film exposed to high vacuum (20-50 microns)3 and leaves the vessel via a barometric leg, entering the lead pot. The lead leaves this pot at 540-560° C., containing 0·03 to 0·06 per cent Zn, which is removed, together with residual antimony of 0.02 to 0·06 per cent, by a separate final refining process.

Jan 1, 1956

By Ashley P, Neale T

Alluvial gold was discovered on Sudest Island in 1888, and by 1893, an official production of 10 000 oz had been won by expatriate miners from shallow alluvial and colluvial workings. Hardrock sources were located and while one was developed at Mt Adelaide, production is unknown. Sudest Island comprises mostly phyllites and lesser coarse grained rocks which are cut by metamorphic quartz veins and basic (locally shoshonitic) intrusives. Sheared and altered basalts and serpent- inites represent are believed to be elements of an ophiolitic suite inferred to be associated with metamorphic core complex development and thus similar to tectonic environments on Misima and the D'Entrec- asteaux Islands. No epithermal-style quartz suggestive of a target similar to that on Misima Island has been identified on Sudest. A hardrock source for the alluvial and colluvial gold is interpreted to be metamorphic quartz veins similar to those in the Bendigo- Ballarat Zone of central Victoria, possibly remobilising gold derived from the meta- sedimentary and meta-igneous rock pile. The present focus is on development of a small scale alluvial gold mining operation in conjunction with exploration for hardrock targets. This latter programme remains at a reconnaissance stage.

Jan 1, 1991

By Nageswararao K

A series of tests was carried out on one of the rock-pebble milling circuits treating complex nickel ores at Kambalda Nickel Operations of Western Mining Corporation. A mathematical model to describe the behaviour of a 508 mm hydrocyclone was developed from the data.A "flat" reduced efficiency curve was observed for the system. This was attributed to a marked difference in the specific gravity of different size fractions of the feed. A modified approach in describing the shape or the reduced efficiency curve resulted in accurate prediction of the hydrocyclone performance.

Jan 1, 1981

When asked to lecture at Bendigo on the geological factors that determine the depths of ore deposits, I hesitated for a little before agreeing to lecture on the theory of deep ores in the city world famous as the pioneer of deep gold mining. If there be one place, wherein the conditions of deep-seated ore deposits should be sufficiently well understood, it is the city where the 180 mine made its bold plunge to previously neglected depths; and where the record of that famous mine has been broken by the skill of the managers, and the pluck of the proprietors, of the New Chum Railway and Lazarus mines.In the face of such practical triumphs, theoretical discussion may seem a waste of time, especially since it is often dedared that the existence of such deep-seated ores was denied by geological theory. This assertion is, however, startling since the oldest and best supported geoiogical theory of ore deposits, has taught for more than a century tliat ores must descend far below the regions of practical mining. This charge against Victorian geologists is generally based on opinions attributed to the late Sir Fredrick McCoy. It has been repeatedly affirmed that he declared that gold cannot occur pelow a depth of 300 feet. But so far I have not been able to discover that McCoy ever made any such assertion or ever held such a view.

Jan 1, 1902

Gold in the stibnite veins of Costerfield, Victoria, was described in 1922 1, prior to any mineragraphic examination, as (a) free yellow gold (b) free rusty gold and (c) combined gold. The free yellow gold occurs in quartz and will amalgamate with mercury. The free gold of dull, rusty or copper-red colour occurs in massive stibnite and has been stated to resist amalgamation with mercury. The dull colour is only skin deep and the colour is bright when the rusty gold is scratched. The appearance of the rusty gold is spongy or cellular and it generally occurs near small cavities in the stibnite. The suggestion that the cellular character indicated the removal of a certain amount of stibnite leaving a residue of se.condary gold cannot be sustained.It now appears probable that the rusty gold is formed by the primary dissociation of a gold antimonide and is distinct in origin from the normal yellow gold which is deposited with quartz or stibnite from auriferous mineral solutions.The combined gold referred to in the earlier paper was the gold contained in the stibnite as revealed by assay. Such gold was at first thought to be either dissolved in the stibnite or else present as free interstitial particles too minute for observation in transmitted light in thin sections.Subsequent examination of numerous polished,surfaces disclosed the small particles of gold occurring in the grain boundaries in aggregates of fine grained stibnite 2. The assumption that all the gold in the stibnite, as revealed by assay, occurred in this way is now known to be incorrect, because limited amounts of a gold antimonide have been found in the veins.

Jan 1, 1952

The area (330 sq. miles) shown on the map of the Brocks Creek District (Fig. 1), was mapped by the Northern Territory geological party of the Aerial, Geological and Geophysical Survey of Northern Australia. This work was done in two stages:-(i) In 1935, an area of 30 sq. miles around the Golden Dyke mine was mapped by P. S. Hossfeld, Senior Geologist, and A. H. Voisey, Assistant Geologist. The results were described in a detailed report (10).(ii) In 1939, an area of 300 sq. miles in the Brocks Creek district was mapped by C. J. Sullivan (Senior Assistant Geologist), and V. M. Cottle and S. N. Kiek (Assistant Geologists) under the general supervision of P. S. Hossfeld (Senior Geologist).An outline structural map, together with some geological notes was published (1), but that map does not show the amphibolites, and the relationship between ore occurrence and general geology is not emphasised. The publication of the detailed maps and reportwas postponed indefinitely as a result of war. The original mapping was based on air photographs with a scale of approximately 1 in. to 1,200 ft., and all detail which could be shown at that scale was mapped. Features recorded included rock types, details of structure, mineralisation, and surface workings, creeks and soil boundaries. Underground mapping was also carried out. The present map is much simplified from the original, but it is hoped that it shows sufficient information to reveal close relationship between structure, granite, sills of amphibolite and gold occurrence. About 50 per cent. of the area is covered by deep soil or alluvium, and in these portions the geology of the underlying rocks was not determined with accuracy, though in many places strike trends could be deduced from air photographs.Because the A.G. & G.S.N.A. had published the geological notes and map referred to above, and because the publication of the detailed report and maps is still postponed indefinitely, approval has been given by the Bureau of Mineral Resources, Geology and Geophysics (which took over the affairs of the A.G. & G.S.N.A. at the termination of its operations) to the preparation of the present paper so that information would be available to the public.The views expressed in this report are those of author. The results of the investigation suggest that in areas where granites are predominantly concordant with bedding, ore deposits may be found at approximately the same stratigraphic horizon. It is thus important to correlate beds even though their relationship may have been obscured by faulting and folding.

Jan 1, 1950

The mining industry to the lay mind is one which appears peculiarly dangerous, partly because the accidents which take place are usually of a very tragic nature, and partly because other, industries claim victims more from disease than fromviolence, and their fatal nature is not advertised to the same degree so that in spite of this idea of unusual risk, it is a fact that mining will compare favourably, as regards vital statistics, with nearly all other trades requiring special training.Neverthelessthere are a larger number offatal and serious accidents occurring year by year than one would like to see, and could the deaths which take place by accident be eliminated, it is safe to say that mining would become one of the most healthy of all species of skilled labour. If we examine the accidents appearing yearly in the reports of the Mining Departments of the various colonies, it will be at once admitted that many of them need riot, and in many cases ought not to, have occurred.It is, therefore, the object of tbis essay, to pass under review the ordinary precautions which should be adopted to minimise, as far as possible, the dangerous factors whereby fatalities are brought about.

By A. J. MOORE

When the writer first saw the square-set timbering, he was at once impressed with the fact that the frames made by the sets, along the lode and across it, were composed of panels with rectangular openings, and it was puzzling to understand howsuch a collapsible construction could resist pressure that came unevenly on it. Later he learnt that the sets did not satisfactorily resist such pressure, but mullock filling had, to a great extent, to undertake this duty for them. So it appeared that the setswere practically an expensive scaffolding, enabling the miners to work in the face and carry the stope forward, till the filling was put in behind them to take the pressure of the roof and sides of the excavation. Of course some of the pressure is takenby the sets, but this is because "the set timbers prevent the filling being done perfectly; if it were practicable to remove the sets before filling, the filling by itself would more effectively support the back and wall, than do the combined sets andmullock. On the whole, therefore, the sets can hardly be said to be of much benefit where pressure has to be resisted. Despite this, the system has been of immense service in mining wide lodes, but for all that, it can only be pronounced a makeshift.This is no reflection on Deidesheimer, the famous originator of the square set, for, as will be shown later on, this way of...

Jan 1, 1912

(Published by courtesy of the Great Boulder Pty. Gold Mines, Limited)1. INTRODUCTIONThe faults described in the following paper are of a somewhat unusual character, and have presented a serious problem both in the development and mining of many ore-bodies on the Eastern side of the Boulder Belt. They are mentioned only briefly in the literature of the field, but were observed by, both Stillwell (1)t and Gustafson (2), and have been studied by other geologists and operators in various parts of the "Belt." Their effect on the lodes of Hamilton Section, Great Boulder Mine, was described by King (3) in 1937, and, during recent years, they have been encountered in most of the Great Boulder workings extending east of the Boulder Dyke.Although this paper is based mainly on a study of faulting and development problems on the Great Boulder mine, the general conclusions reached may be applicable to the solution of similar faulting problems in other mines throughout the field.In order to arrive at a clear understanding of the somewhat complicated relationships which the east-dipping faults bear to the lode systems it will be necessary to give a brief outline of the salient geological and structural features of the "Belt" before proceeding to describe the faults themselves.2. GENERAL GEOLOGYThe most recent descriptions of the geology of Kalgoorlie are those by Stillwell (1) and Gustafson (2) and the reader is referred to these as representing the basis of current knowledge of the geology of the field.The Boulder Belt is comprised of a central core of altered quartz dolerite which is flanked on either side by fine grained greenstones and lavas, usually referred to as the calc schists. Down the centre of the quartz dolerite mass there is an infolded bed of slate (2, p. 105) which has been intruded in lit par lit fashion by albite porphyry; the composite body of slate and porphyry so formed is known as the "Boulder Dyke." Numerous smaller porphyry dykes intrude both the quartz dolerite and the calc schist; these vary in composition and range from chloritised hornblende porphyrites to albite porphyries.The whole of the rock assemblage has been subjected tG a considerable amount of folding, faulting, shearing and fracturing, the greater part of which took place before the formation of the lodes.

Jan 1, 1941

A recently developed technique for use in collieries is described in which samples of gas of relatively high vitiation value are obtained from points deep within a developing goaf by means of pipes. This technique prevents dilution of small quantities of carbon monoxide by large quantities of fresh ventilation air and eliminates interference from shotfiring gases. By using the technique it should be possible to assign a characteristic ratio of carbon monoxide to oxygen consumed to any district and to predict the onset of heatings.INTRODUCTIONGas analysis has played a vital role in detecting heatings in collieries all over the world. By analysing return air from a district and by calculating the percentage ratio of volume of carbon monoxide found to oxygen consumed (known simply as the "carbon monoxide ratio") it has been found possible, in many cases, to assign a characteristic ratio to a district under consideration. This characteristic ratio serves as an index of the spontan~ous combustion tendency of a goaf area. Any definite and consistent increase in the ratioabove the normal figure· indicates that a heating is developing and hence adequate preparations may be made to deal with the trouble.This ratio technique was developed by Graham (1920-21) who found (Table 1) that the temperature of oxidizing coal was directly related to the ratio obtained from analyses of the effluent gas.Until recently, most attempts to employ a similar technique in collieries working the Greta Seam (N.S.W.) were not successful. From experience gained over the past few...

Jan 1, 1961

The alkaline ethylenediamine tetra-acetic acid (EDTA) leach process for extracting tungsten from scheelite (CaW04) ores has been examined for the treatment of low grade (<0.5 per cent WO,) residue dumps. The process has been considerably simplified by applying solvent extraction directly to the leach liquor.Ammonium paratungstate is thereby produced in a one step process and this obviates the need to physically recover EDTA prior to recycling. This modified process should be an economical method of tungsten extraction.

Jan 1, 1983

By M Bannear, C Stanton

Since 2008, Arrium has been developing and commissioning a new low-grade hematite ore benefication plant (or OBP) at its Iron Baron mine site.The Iron Baron mine, which was closed in the 1990s, could not consistently yield the high-grade hematite required for pelletising. However, in todayÆs market, the 12 Mt of waste dumps represent a significant low-grade hematite resource, ideal for benefication.Initially, an internal scoping study and several sampling campaigns were conducted to determine the ability to upgrade the available low-grade dump material to a product suitable for export. Test work was conducted at Mineral Technologies (formerly CPG), and included high intensity magnetic separation, spiralling and jigging. Due to promising results from a wet processing circuit, Arrium engaged Mineral Technologies to design a flow sheet that could provide 1 Mt/a of a mixture of high-grade lump (-32 + 8 mm) and fines (-8 mm) products for export.With construction of the plant completed in late January 2012, Arrium, in conjunction with Mineral Technologies, began two commissioning phases. Each phase ended with a toll gate to prove the plantÆs capacity to reach rate and desired grade. After an initial period of running on water, feed solids were introduced to the plant and troubleshooting of bottlenecks began. The first toll gate, whereby the plant was required to run for 24 hours at an average feed rate of 200 t/h (80 per cent of design rate), was completed on the 1 March 2012. Further troubleshooting and resolving of issues allowed the plant to steadily increase feedrate while maintaining good availability and grade. The second toll gate required the plant to run for 72 hours at an average feed rate of 200 t/h while meeting grade, yield and water consumption targets. Sampling campaigns were conducted during this period to track the performance of key equipment. Completion of the test, and full handover of the plant to Arrium, was completed on the 21 April 2012.Although the formal commissioning phases had been completed, ongoing optimisation of the OBP continued, ensuring that all major equipment was working to produce the optimum yield and grade. Sampling campaigns were conducted on the jigs and spirals, with results and correlations used for operations documentation.Overall, with successful completion of the final acceptance tests, the commissioning of the Iron Baron OBP has been established as a major success achieving all production and quality targets as per the original design intent.This paper will focus on the successful commissioning and ramp-up performance of the plant however reference will also be made to the key development stages involved with the development of the project.CITATION:Stanton, C and Bannear, M, 2013. ArriumÆs Iron Baron hematite beneficiation plant - a success from start to finish, in Proceedings Iron Ore 2013 , pp 547-552 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013