Search Documents

IN this paper it is proposed to present certain features of operating practice at the Port Pirie works of The Broken Hill Associated Smelters Proprietary Limited, in the smelting in a blast furnace of lead ores carrying a high concentration of zinc.The subject matter selected for presentation is:(i) The effect of zinc on lead blast-furnace operations, together with an outline of the methods adopted in actual practice in dealing with the zinc problem.(2) Development of the height of tuyere above the bottom of the jacket, and the extension of the tapping interval and the combined effect of both factors upon the lead content of blast furnace slag.It will later be seen that one phase of the investigation carried out in connection with the effect of zinc on blast-furnace operations was largely responsible for the decision to increase to a marked degree the height of the tuyere above the bottom of the jacket.Due to this interdependence, it has been considered advisable to deal with the two features above mentioned.The high concentration of zinc in the lead-bearing materials smelted at Port Pirie has brought with it those troubles which are associated with zinc in the smelting operation.In the early stages of the history of The Broken Hill Associated Smelters Pty. Ltd. the trend towards increasing cost for labour, fuel, and stores, etc., rendered it necessary to increase the lead content of the charge, and reduce to a minimum the quantity of barren flux used.

Jan 1, 1931

A new lead refinery with a capacity of 230,000 tons per year commenced operation at Port Pirie in October, 1959. This plant superseded the refinery which had operated from 1933 with the advent of the continuous lead refining process. The incorporation of new equipment following local metallurgical developments, together with the overseas demand for lead of extremely low antimony content createddifficulties in operating the original plant. The new refinery project was undertaken to cover this disability and to gain the full advantage of the new processes.Desilverising and softening are carried out in units identical in size to those used previously. Metallic zinc is recovered from the entire output of desilverised bullion by vacuum distillation. Final refining is carried out by batch treatment with caustic soda yielding lead of purity previously unattainable at Port Pirie.These two processes replace continuous dezincing by oxidation, a high temperature process which caused large quantities of lead and antimony to be recirculated. The final stage is a batch process; therefore the product composition can be checked before casting. Individual batches can be adjusted to produce special alloys to consumer's specification.Improved casting equipment allows the quantity production of pigs of good physical characteristics either as 56 lb bars or 2000 lb pigs.This, together with the high purity of the lead, assures the Broken Hill Associated Smelters Pty. Ltd. (RH.A.S.) position in world markets.Automatic control systems are extensively employed, particularly on the vacuum dezincing unit.The anticipated financial benefits have been achieved mainly by a reduction in the tonnage of recirculated materials, a smaller labour force, and reduced maintenance requirements.INTRODUCTIONIn December 1956 a decision was made to build at Port Pirie a lead refinery on a completely new site, and in October 1959 the new refinery was brought into operation. This plant superseded the lead section of the old refinery which...

Jan 1, 1963

By J Cook

In this paper we present a case study of the challenges and opportunities associated with the development of cultural heritage management strategies at the Lihir gold mine in Papua New Guinea. We discuss the contextual drivers and constraints, and outline the ways in which Lihir Gold Limited is aiming to set new industry bench marks for the region through the development of values-based best practice cultural heritage management programs. This approach is largely based upon a compliance partnership with a local stakeholder group. We argue that such partnerships are a prudent means of mitigating company risk, while constituting a far more necessary tool for local people in the reconceptualisation and negotiation of the experiences of significant social change and modernisation experienced in the context of recent resource development.

Jan 1, 2009

Formation of either sodium jarosite or lead jarosite from concentrated chloride solutions containing small concentrations of sulphate has been demonstrated. Sodium jarosite is precipitated at 95-100°C from FeC13-FeCI2-NaCI-PbCI2 solutions to which was added Na2SO4 or Li2SO4 in amounts greater than 0.05 M. In the absence of alkali metal ions capable of forming jarosites, lead jarosite was precipitated from either FeCI3-PbCI2 or FeCI3-FeCI2-LiCI-PbCI2 solutions to which had been added small amounts of sulphate. Many of the factors affecting jarosite precipitation from chloride solution have been elucidated, and the most critical were sulphate concentration and initial pH. Concentrations of HCI in excess of O. I M essentially suppressed the production of jarosite in chloride media. Alkali jarosite, precipitated in the presence of dissolved lead, incorporates a small amount of this metal into the alkali jarosite lattice. Small but significant amounts of copper can also be incorporated into alkali jarosite and the amount is further increased in the presence of lead. Other divalent base metals such as Zn, Cd or Ni are not significantly precipitated. Sulphate control in either FeCI3 or FeCl3-NaCI leaching systems could likely be maintained by jarosite precipitation provided that the acid concentration of the solution was low.

Jan 1, 1981

By T Christie

Tertiary volcanic rocks make up a significant proportion of the surficial cover rocks of New Zealand, especially in the Taupo Volcanic Zone. Industrial minerals that are associated with or derived from the volcanic rocks include: amorphous silica, allophane, bentonite, diatomite, ignimbrite building stone, illite clays, halloysite clay, obsidian, perlite, pumice, sulphur, titanomagnetite ironsand and zeolite. Of these: bentonite, ignimbrite building stone, perlite, pumice and titanomagnetite ironsand have been mined and processed for 20 to 30 years, but many of the others require further characterisation of the resource and/or development of markets.   We have compiled interim mineral deposit models for halloysite clays in rhyolite and for zeolites in altered vitric tuffs. These models include geological and mineralogical attributes, which are linked to the underlying volcanic and geothermal processes that have produced the minerals and their source volcanic rocks. Halloysite clay deposits at Matauri Bay (Northland) have formed from hydrothermal alteration and weathering of rhyolite. Clinoptilolite + mordenite zeolite deposits in the Ngakuru area (Rotorua district) have formed from hydrothermal alteration of volcanic glass in lacustrine sediments and ignimbrite. Further refinement and application of these models will result in a better understanding of the mineralogy, localisation and origin of the deposits, with consequent applications in exploration and resource assessments.

Jan 1, 2001

It is now five years since the advent of gold-dredging in Australia, the State of New South 'Wales, or colony as it was, being the first to adopt this system of gold-getting, and the credit of its introduction rests with a member of this Institute, Mr. Chas. L. Garland, who commenced operations with his dredge on the Macquarie River, at the junction of the Muckerawa Creek, in the month of March, 1899. In this paper it is intended to give a brief history of the career of the gold dredge in New South Wales from that relate up to the present time, during which period the writer, as a designer of many dredges, has been constantly in touch with the subject in all its phases in this State; the points noted are the outcome of his observation in a general way, and to a great extent are apart from the design proper.Gold-dredging in New South Wales up to the present moment can hardly be designated an unqualified success...

Jan 1, 1904

The ultraviolet spectrum of isopropyl ethylthionocarbamate (the principal constituent of Dow flotation collector Z-200) in water and of Z-200 itself in water was found to have an absorption peak at 242 nanometers(nm). The height of this peak was found to be directly proportional to isopropyl ethylthionocarbamate concentrations up to 15 p.p.m. Z-200 contains about 90 per cent isopropyl ethylthionocarbamate and the heightof the peak was proportionately lower, but obeyed the straight line relationship up to 15 p.p.m. This showed the potential value of spectrophotometric measurements for the determination of Z-200 residuals in flotation liquors.Methyl ethyldithiocarbamate (an impurity in Z-200) increased the peak height slightly, but other impurities in Z-200, xanthates, and most inorganic salts present in flotation liquors do not interfere. However nitrate ion and thiosulphate ion have absorption peaks which overlap the isopropyl ethylthionocarbamate peak.The simplest general method to overcome this effect is to extract the isopropyl ethylthionocarbamate into cyclohexane and to measure the absorbance of the extract.The maximum absorbance of the cydohexane extract was at 247 nm and the peak height at this wavelength was found to be directly proportional to the isopropyl ethylthionocarbamate or Z-200 concentration in the original aqueous solution. An alternative method is to measure the spectrum of the original aqueous solution using the aqueous raffinate from extraction as a reference solution. This gives the spectrum due to isopropyl ethylthionocarbamate alone and measurement of the absorbance at 242 nm gives the concentration in the original aqueous solution. Both methods give the same value for the concentration of isopropyl ethylthionocarbamate in the original solution.

Jan 1, 1969

Role of Bubbles in the Action of Flotation Agents

Sep 13, 2010

Gold was determined directly in eight different mill cyanide solutions, by atomic absorption spectroscopy in an acetylene-air flame. Some of the mill solutions were diluted with water to bring them into the most sensitive absorption region (5-50 p.p.m. Au) whereas those solutions with very low gold content «2 p.p.m.) were concentrated by evaporation.Calcium was complexed with ethylene diamine tetra-acetic acid (EDTA) to avoid the undesirable effect of a precipitate on atomization.When added to standard gold solutions, EDTA had no effect on absorption, nor did any of the impurities common in mill cyanide solutions.Known amounts of gold, ranging from 2 to 30 p.p.m., were added to mill solution'aliquots and recovered to within 100 ± 2·5 per cent. For duplicate determinations under normal worKing conditions, standard deviation was 1·32 p.p.m.Excellent agreement was found between atomic absorption gold values and accurate fire assay values.INTRODUCTIONAtomic absorption spectroscopy has been shown to offer a rapid and accurate method for the determination of trace amounts of a number of metal ions. In the field of primary metallurgy atomic adsorption has been used for routine determinations of lead, copper, silver, zinc, cadmium and iron in a variety of raw materials and intermediate products.The scope of atomic absorption spectroscopy was reviewed recently by Willis (1963).The noble metals silver, gold, platinum, rhodium and palladium were determined by atomic absorption from chloride solutions by Lockyer ·and Hames (1959). In their determination of gold down to 1 p.p.m., they found no interference from the noble metals, nor from considerable excess...

Jan 1, 1964

Stratiform lead-zinc mineralization at the Pegmont prospect occurs as a 4-6 m thick body interbedded within arkose, schist, amphibolite, and pegmatite of the Kuridala Formation in the Eastern Belt of the Lower Proterozoic of northwest Queensland.The overall structure of the body is that of a strongly crumpled east-dipping sheet. In detail it is subjected to complex and irregular deformation.Gossaneous outcrops of the mineralised body are anomalous in Pb-Zn-Ag content and have been traced, discontinuously, over about 36 km2 in a NNE-trending belt.Below the zone of oxidation, which reaches 25-40 m below the surface, the primary sulphides are galena, sphalerite, and pyrite.Drilling on a 2 km2 area near the discovery outcrops indicates fairly uniform grades of lead and zinc.Changes in thickness of the mineralised body are gradual.

Jan 1, 1977

Most analysts determining tungsten trioxide in low grade samples are aware that colorimetric procedures do not possess the inherent disadvantages of gravimetric methods operating on milligram quantities of tungsten trioxide. Apart from the inaccuracies associated with weighing four or five milligrams of ignited oxide in a platinum crucible of about 30 gm. weight with a large surface area to absorb moisture, using a 5 gm. charge on samples less than about 0·15 per cent tungsten trioxide, it is extremely difficult toget complete or pure precipitation of tungsten with cinchonine, cinchonine plus alpha benzoin oxime, rhodamine B or any other of the commonly used precipitants. Table 2', No. 8, illustrates the low results obtained by gravimetric as opposed to colorimetric procedures. In addition the colorimetric determination requires only a small portion of the time consumed by gravimetric practices and the increased accuracy obtainable in low ranges together with the saving in time made it highly desirable to develop a colorimetric method suitable for King Island ores.The most commonly used colorimetric method is that introduced by Feigl and Krumholz (1932), since modified by various investigators (Grimaldi and North, 1943; Sandell, 1946; Westwood and Mayer, 1947; Gentry and Sherrington, 1948; Freund, Wright and Brookshier, 1951; Grouthamel and Johnson, 1954; and others). Stannous chloride is used to reduce tungsten followed by colour development with a thiocyanate, usually sodium, potassium or ammonium.Other reducing agents have been proposed (Emery and Curtis, 1948), but only in recent years have the conditions governing maximum colour development been fully estab...

Jan 1, 1958

IN the recent monograph on Broken Hill, N.S.W., by E. C. Andrews,* two independent petrological reports appear as Appendices 1 and n, by W. R. Browne and F. L. Stillwell respectively. In these considerable differences of opinion occur. Andrews contributes to some of the questions at issue, but no analytical review of the differences appears in the body of the report. Their development may invite question, and the following notes have been prepared partly in explanation and partly as a summary of some of the divergences. The soope of Browne's report extends over the whole district of Broken Hill, while Stillwell's deals with the rocks within 25 chains of the main lode. The more difficult and important rock-types occur in both areas, raising similar questions. In both cases observations extended beyond the limits of the prescribed areas. Broadly, Browne faces his problem as a study of a series of primary igneous rooks, acid and basio, whioh are intrusive into a series of sillimanite gneisses. The development of the sillimanite gneisses is regarded as belonging to an earlier period than the intrusion of the igneous rooks, while the gneissio structures of the latter are features which are incidental to their orystallization, and are not acquired subsequent to their consolidation. He finally produoes a picture in which his views of igneous injection and differentiation takes a prominent place. One direct result is the claim that three separate periods of metamorphism have oocurred in the Broken Hill area. Stillwell primarily examines the rooks as schists and gneisses since their present dominating features have been acquired during metamorphism. The effort is made to understand suoh differences as might arise from differing conditions of metamorphism upon rocks of similar and different oonstitution. The aim is to divest the rocks of those oharaoters which are due to metamorphism before approaching the questions of intrusive relatio'nships between igneous rocks andsediments.

Jan 1, 1924

By D Craw, D Wilson, D Chappell

Gold is extracted by cyanidation of a sulphide-rich concentrate at Macraes mine, and after cyanidation, the concentrate is discharged to tailings impoundments. The concentrate tailings were discharged to a dedicated concentrate impoundment from 1989 to 1993, afterwhich they were blended with the flotation tailings. Since mid-1998, concentrate tailings have been redirected to the dedicated concentrate impoundment. The concentrate tailings contain up to 1 ppm gold, and will be reprocessed in the future. However, it is a regulatory requirement that a contingency plan be in place to rehabilitate the concentrate tailings should the mine operation cease for any reason. Initial predictions suggested that the sulphide-rich tailings would oxidise and acidify, creating a potential long term environmental problem. Investigations of the state of the tailings after 4 years show that these predictions were overly conservative. Only minor oxidation has occurred in the upper 2 metres of the tailings where the pH has locally dropped from 10 (discharge condition) to between 7 and 8. Below 2 metres, the tailings are essentially unchanged from their deposition state. The low rate of change in the tailings is due to their very low permeability which in turn is a consequence of the fine grain size (ca. 15 ¦m). Dewatering is extremely slow, and incursion of oxygenated water is negligible. Calculations suggest that water movement over 30 m will take at least 100 years and possibly 1000 years. The contingency plan is to capitalise on the very low permeability and keep the tailings from drying with a semipermeable cap. A layer of limestone will be added to the top of the tailings, beneath the cap, to enhance alkalinity of any percolating water. If acidification does occur, contrary to expectations, any acid produced will be neutralised by underlying calcite-bearing schist, schist in the concentrate impoundment wall, and the flotation tailings immediately downstream. In addition, dilution by alkaline ground and surface waters would further ameliorate any acidic discharge.

Jan 1, 1998

The Oregon-Idaho graben evolved after widespread tholeiitic flood basalt volcanism associated with the arrival of the plume head of the Yellowstone hotspot beneath southeastern Oregon approximately 17 - 16 Ma. The north- to north-northeast-trending, 50 km-wide graben evolved between 15.5 and 10.5 Ma during east-west extension. The graben is part of a middle Miocene back-arc rift (1100 km long) that includes the northern Nevada rift, the Baker and LaGrande grabens, and the Chief Joseph dike swarm of the Columbia River Basalt Group. The graben ceased to be a volcanotectonic depression as the cross-cutting western Snake River plain began to evolve at approximately 10.5 Ma. At about 14.3 Ma and continuing to approximately 12.6 Ma the Oregon-Idaho graben began to break up into subbasins that were bounded by intragraben fault zones. The break up was accompanied by a change to calc-alkaline volcanism that persisted within the Oregon-Idaho graben until 8.1 Ma, approximately 2.5 million years after subsidence within the graben ceased. Three intragraben fault zones have been identified and a fourth is inferred. The easternmost, the Devils Gate fault zone, coincides with the magmatic axis of the graben at approximately 14.3 Ma. By approximately 13.5 Ma the magmatic axis had shifted to the west along the Dry Creek Buttes and Wall Rock Ridge fault zones. A diffuse magmatic axis developed at approximately 12 Ma farther to the west where the fourth intragraben fault zone is inferred. In addition to serving as conduits for the ascent of basalt, basaltic andesite, rhyodacite, and rhyolite magmas, the zones focused the discharge of large geothermal systems. The intragraben fault zones display a common evolutionary pattern. The 2 to 3 km-wide zones initially control the distribution of facies in volcaniclastic sediments and the location of basalt hydrovolcanic vents. During this stage, the fault zones may have had no surface expression other than a low elevation change on a relatively low-relief landscape. As relief developed by continued deformation along the fault zones, strike-length of individual faults increased and weakly consolidated volcaniclastic sediments, silicified sediments and hot-spring sinter, and palagonite were eroded from the uplifted blocks and deposited in neighboring subbasins. It is during this stage that the large hot-spring precious-metals bearing prospects evolved. Displacements of over 150 m on a few faults within the zones and possible reversal of the sense of displacement along the zones occurred in this final stage of development. Locally, the fault zones were remobilised during the subsidence of the cross-cutting western Snake River plain. The intragraben fault zones within the Oregon-Idaho graben illustrate the relations among syntectonic volcanism and sedimentation and the evolution of geothermal systems within continental rift systems.

Jan 1, 1995

By Parker A. J, Ruane M, Wadley L. G B

Copper, sulphur, nickel, cobalt, palladium, silver, and gold can be recovered from the copper sulphide precipitated from the "copper boil" of the Sherritt-Gordon nickel process used at Western Mining Corporation's Kwinana nickel <refinery. The method is based on an oxidative ammonia leach of copper, nickel, and the precious metals at temperatures below 40°C to produce, in part, elemental sulphur, in the residue. This is followed by heating to decompose thiosulphate and remove some ammonia with precipitation of some of the copper, palladium, gold, and silver. Addition of sulphur dioxide to pregnant liquor precipitates copper, as either Chevreul's salt or copper(I) ammonium sulphite, together with the remaining gold and silver. Less than 10 per cent of the dissolved palladium and less than 1 per cent of nickel and cobalt precipitate to this stage.In one option, the Chevreul's salt is dissolved in a solution of copper(II) sulphate, acetonitrile, and water to generate a solution of copper(I) sulphate. Gold and silver do not dissolve. The solution of copper(I) sulphate is thermally disproportionated by distilling acetonitrile to give exceptionally pure copper powder, with desirable characteristics for powder metallUrgy. Nickel, cobalt, and ammonium sulphate are recovered from the motherliquor of the Chevreul's salt precipitation by return to the Sherritt-Gordon process, where recovery procedures already exist. Palladium is recycled for eventual removal as a sulphide with the gold and silver.In the other option, solid copper(I) ammonium-sulphite is <thermally disproportionated in water at 150°C to copper powder.

Jan 1, 1978

Effect of Hydrophobicity and Frother Concentration on Bubble-Particle Interactions in Turbulent Flow

Sep 13, 2010

A predicted increase in aluminium production and the possibility of a diminishing supply of petroleum coke for anode electrodes in alumina reduction cells makes it desirable to find alternative electrode materials. Browncoal char, with a lower ash content and with an elemental purity similar to petroleum coke, was produced by leaching in hydrochloric acid, washing with water, and charring at 1,150°C. The cost of processing is estimated tobe competitive with petroleum coke.Without further processing the bulk density and real density were undesirably low, but by briquetting the coal before charring and crushing, the bulk density was improved to 92 per cent of the petroleum coke value andthe particle density was improved to 92 per cent of the density of petroleum coke by water displacement or 75 per cent by mercury displacement.Pre-baked electrodes were prepared from the char alone, mixtures of petroleum coke and char, and from petroleum coke alone, all bonded with coal tar pitch.The electrodes were tested for the usual physical properties and were evaluated for performance in a laboratory size alumina reduction cell.Electrodes based on brown coal char alone were found to be inferior in physical properties and performance, but mixtures of the char and petroleum coke, despite poorer density, electrical resistivity, and carbon consumptionon a theoretical basis, in performance tests gave up to 17 per cent better carbon consumption per weight of aluminium produced and 21 per cent better electrical current efficiency than the electrodes based on petroleum,coke alone.It is suggested that larger scale tests are warranted.

Jan 1, 1971

By D Brouwer, P Wild, B Belle

Due to the steep geo-thermal gradient in Bowen Basin area, as underground coalmines reach increased depths of extraction, the Bulk Air Cooling (BAC) requirements will increase as opposed to cooling the workplace using the ventilation means alone. One such mine has already been using a 4 MW surface BAC plant for the last six years to manage the working temperatures with reduced cooling efficiency as the mine expands. Due to the horizontal nature of the longwall mine layout, distances from the working face to intake shafts are rapidly expanding to over 6 km as opposed to the vertical mine layout of a hard rock mine. To improve the positional cooling efficiency, reduced panel pressure differentials, improved rib emission gas management, and intake dust management, small diameter intake shafts were located on the inbye end of production panels and halfway up the development panels with localised mobile small BAC plants. This paper summarises the results of extensive underground data of this innovative cooling concept for development and retreating longwall face heat management compared to a larger remote BAC plant.CITATION:Belle, B, Brouwer, D and Wild, P, 2017. The use of mid-panel ventilation shafts to improve positional cooling efficiency in a Bowen Basin longwall mine – a case study, in Proceedings Australian Mine Vent Conference 2017, pp 217–224 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

By X Dahe

SLon vertical ring and pulsating high gradient magnetic separators (VPHGMS) possess the advantages of high efficiency and high reliability in beneficiating weakly magnetic minerals. In recent years, models SLon-2250, SLon-2500, SLon-3000 and SLon-4000 have been developed. This paper gives several examples of their applications in oxidised iron ore and ilmenite processing flow sheets to improve iron and ilmenite recoveries.CITATION:Dahe, X, 2017. Recent development and application of SLon vertical ring and pulsating high gradient magnetic separators in the iron ore and ilmenite processing industries, in Proceedings Iron Ore 2017, pp 461–466 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By H Peiming, W Sakurai, Y Matsuhisa, H Shimazaki, Y Fukahori

Oxygen and carbon isotope mapping of hydrothermally altered wall rocks was applied to the blind ore prospecting of skarn Pb-Zn deposits in the Kamioka mining district, centralJapan, where the wall rocks consist of heterogeneous rock units. The results (d18OSMOW of -1.1 to +17.3ë and d13CPDB of -5.0 to +4.8ë for limestones, and d18OSMOW of -0.8 to +12.5ë for silicate rocks) show isotope zonations of the wall rocks with depletions in heavy isotopes (18O and 13C) toward the centre of mineralization. The isotope zonations likely formed by interaction of migrating thermal waters with the wall rocks during the mineralisation. The heavy-isotope depleted zone, which indicates higher temperature or higher water-to-rock ratio of the system, occurs in the footwall of a fault, indicating that the fault played the role of main conduit of the ore-forming fluids. A heavy-isotope depleted zone was also found in an area, where significant mineralisation had yet to be identified. Recent drilling in this area has intercepted a zone with a grade of 16.0% Zn, 0.8% Pb, and 35g Ag per metric tonne at a depth of about 360 m.

Jan 1, 1995