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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

The Manto Verde mine is found in the coastal ranges of the Atacama desert, 1000 km north of Santiago, Chile . The deposit is a fault-breccia specularite-oxide copper mineralisation hosted by the Jurassic andesites of La Negra Formation. It is located in a tensional fault that joins twoparallel arms of the Atacama Fault. The mine is in feasibility study: reserves are of the order of 60 Mt at 0.9 wt per cent soluble copper; mining will be undertaken at a rate of 11 000 tpd utilising an open pit and the ore will be heap-leached with acidified sea water, with copper recovery and by SX/EW.

Jan 1, 1992

The granulites and related "dry" igneous rocks tend to be passed over during exploration for metals. Preliminary data show that high trace concentrations of eu, Ni, and other metals of economic interest are commonin orthopyroxene and some of the other granulite minerals. During retrograde metamorphism of granulites, pyroxenes are converted to amphiboles or phyllosilicates, and significant quantities of metals are released andbecome available for incorporation into new mineral phases, or may be transported elsewhere. S-rich scapolite is the normal scapolite of granulites. Its retrogression to secondary plagioclase provides much S which scavengesCu and Ni, from pyroxenes undergoing retrogression, thus producing ore-fluids. A full analysis of a scapolite with 5·10 per cent SOg is given.Beryl is unstable in granulites but the rare Be mineral taaffeite (Al4Mg(Be, FeII)Os) with 5·50 per cent BeO occurs in central Australia as a pale green tabular mineral easily confused for chloritoid in hand-specimen.Metamorphic differentiation and mobilization of primary ore concentrations are major factors controlling their post-granulite attitude and grade.Zones of retrograde metamorphism are commonly found cutting or engirdling granulite terranes. As the "volatiles" for the new hydrous minerals of many of these zones are of deep-seated origin and may be juvenile, sulphide mineralization in them may also be of mantle origin. However, it is likely that much of the metal content could be scavenged from the granulites as they are down-graded by juvenile volatiles. Major Bouguer gravity anomalies delineate some granulite terranes (e.g. Fraser Block, Western Australia), and are related to deep-seated geosutures and mantle disturbances.Many granulite terranes are linear belts and appear to be welded to older cratonic blocks.

Jan 1, 1969

Generating short- and long-term mine production schedules in isolation and independently from each other means that only a local optimum can be achieved when each scheduling phase is carried out. The globally optimal solution however, can be achieved when integrating scheduling phases and accounting for the interaction between short-term and long-term activities simultaneously. This paper addresses the task of integrating short- and long-term production plans by combining the short-term objective of minimising deviation to targeted mill feed grade with the long-term objective of maximising net present value (NPV) into a single mathematical model. A case study is presented which compares the present values of the same stope data set scheduled via separate long and short-term models and than by the proposed integrated model which applies a predetermined penalty for each tonne of metal deviation to target for the respective ore tonnage being processed. This allows an operation to obtain a globally optimal scheduling regime when taking into consideration the cost and loss of value resulting from fluctuations in grade to the mill over the short-term.

Dec 6, 2010

Real-Time Integration of Mining and Metallurgical Information for Efficient Use of Energy and Water

Sep 13, 2010

In setting out to describe the methods and machinery employed at Iron Knob the writer does not attempt to give any information as to the situation, topography or geological features of the locality. This, together with estimates of the quantities of ore still available, has been carried out in a most thorough manner by R. L. Jackr and F. R. Hockey. This essay is intended to deal with working methods as they exist to-day, beginning with drilling, blasting, quarry traction, etc., and touching on such details as the supplyof electricity, water and compressed air.At the present time almost the entire output of ore is won from the hill known as Iron Monarch. The form of the hill, a smooth, rounded dome, rising some 640 ft. above the plain and having a base diameter of n miles, lends itself ideally to the "bench" system of open-cut quarrying.Fig. 1 shows the relationship of the benches "A," "B" and "E" in their order of development. Bench "E" is at present the principal working, but, as the greater part of the ore above this level has now been removed, bench "A," some...

Jan 1, 1936

Modelling Channel Scale Flow in Heap Leaching Using Smooth Particle Hydrodynamics (SPH)

Sep 13, 2010

Plant for the production of sulphuric acid from pyrites flotation concentrates was commissioned at Cockle Creek during 1956, to meet increasing demands for commercial acid and superphosphate. Pyrite was chosen as raw material because of the uncertain supplyposition of imported brimstone and the desirability of utilising domestic sulphur.Desulphurisation of the pyrite is performed by two 40-ton per day roasters of the Turbulent Layer type operated under licence from the Badische Analin and Soda Fabrik (B.A.S.F.) organisation. These units are the first of their kind commissioned in the southernhemisphere. Pyrite is fed to the roasters in the as-received un-dried condition. Waste heat steam production is coupled with electricity generation within the plant. Sulphur dioxide is produced at comparatively high strengths and cleaned by conventional cyclone and hot electro-filter equipment.The acid unit has a capacity of 100 mono tons of sulphuric acid per day and includes cooling and wash towers, mist precipitators, a single stage drying tower, 4-pass oxidation section and absorption system.INTRODUCTIONSulphuric acid has been manufactured at Cockle Creek Works since 1913, when the first chamber nitration plant was commissioned. The raw material was brimstone roasted in Herreschoff furnaces. Since that time three additional chamber units have been constructed and have produced acid from brimstone, zinc concentrates, pyrites and -spent oxide, according to changing economic and supply factors.Three chamber units are still in operation. Contact processes have become increasingly important since the first Schroder-Grillo unit was commissioned in 1923. Six of these 5-ton per day units were operating in the mid-thirties, but have since been demolished. Two 15 ton Chemico hot gas contact units commenced operation in 1937 and 1938, and although modified, are still in service.The increasing demand over recent years for sulphuric...

Jan 1, 1957

By Fookes R. A, Bunch K, Gravitis V. L, Watt J. S

The combustible volatile matter in coal mine roadway dusts (CVM) has been determined using x-ray backscatter techniques. The correlation between x-ray and chemical techniques is reasonably good for the 92 samples from collieries on the Bulli seam, and the maximum error expected at the maximum level of 11· 5 weight per cent CVM permitted in the N.S.W. Coal Mines Regulation Act, 1912, as amended, is about ± 2·5 weight per cent. This x-ray technique can be used only when the combustible volatile content of the coal matter (cvm) varies within a limited range, and a separate calibration is required for each coal seam.Portable equipment based on a radioisotope x-ray source ahd digital ratemeter makes possible simple and rapid analysis, and with adaptation to use in coal mines should lead to much more comprehensive testing- ofroadways and hence improved overall prevention of coal dust explosions.

Jan 1, 1977

By Uusna S, Canning R. G, Goodheart B. A

The development of a process for removal of iron oxides from ilmenite is outlined whereby the Ti02 content of Western Australian ilmenites can be upgraded from 55 to approximately 90 per cent. In the first stage, the iron oxides are reduced with solid carbon (coal) to metallic iron. Experimental reductions were carried out in crucibles, a fluidized bed, and a small pilot plant rotary kiln. The reduced ilmenite was then agitated in aerated water, in the presenceof catalysts, so that the iron "rusted" away from the ilmenite grains and the precipitated iron oxide was easily separable by decantation.The influence of variables on the rates of reduction and oxidation are discussed. The oxidation rate was examined for both the physical oxygen transfer characteristics and electrochemically by reference to Pourbaix diagrams, in which redox potential is plotted against solution pH.The upgraded ilmenite is expected to be an attractive material for pigment manufacture, and the iron oxide has prospects of being a marketable by-product. The process may possibly be applied to other ores.INTRODUCTIONThere are extensive deposits of ilmenitic beach sands, Le. iron titanium oxides of the general formula FeTi03, 'occurring in the lower south-west portion of Western Australia, and although there has been considerable commercial development, local producers face keen competition on a freight-cost basis. Thus the removal of the unwanted iron oxide constituent would have the double advantage of reducing the freight differential and presenting a more attractivematerial to pigment manufacturers.

Jan 1, 1965

Hot briquetting is a reliable, fully developed industrial concept for the passivation of direct reduced iron produced with the various processes of direct reduction. During hot briquetting, the large specific surface area of direct reduced iron is drastically reduced, and therefore the well-known problems caused by reoxidation and overheating are avoided. Even the shipping instructions published by the International Maritime Organisation (IMO) confirm that Hot Briquetted Iron (HBI) can be handled and shipped without special precautions. From the mid-1970s until today, after extensive pilot testing of the technology, a number of industrial plants for the hot briquetting of direct reduced iron have gone into operation. Additional hot briquetting plants for already established but also for new direct reduction processes are tinder construction or in different stages of planning. This paper describes the characteristics of HBI and its current industrial application for various Direct Reduction Processes.

Jan 1, 1999

By Robinson KJ

Education in Australia now has to respond to a very wide political and policy agenda. The political emphasis is upon increasing participation and retention rates with a view to greater graduation rates in `high-tech' disciplines. There is an implied linkage between `education' and `economic well-being'. Our argument is that equalitarianism in education tends towards mediocrity. In this context many Geoscience educators view the future with pessimism. The argument is that science has been `sold short' and needs revitalising. We contend that Geoscience coursework should be a feature of both secondary and tertiary education in Australia. To this end we propose six policy initiatives to increase the content of Geoscience in education programmes.

Jan 1, 1989

Notwithstanding full concurrence with the dictum of a famous scientist that "definitions are the most accursed of all things on the face of the earth," in view of the considerable confusion which exists in jigging nomenclature, it is considered advisable to commence this paper with the following explanations of the terms which will be used throughout the text.Jig Bed. The whole layer of material lying on top of the jig screen.Ragging. The layer of denser material lying immediately above the jig screen, which is too coarse to pass through this screen and is confined horizontally by the cells of the top grid.Ore Column. The layer of ore pulp between the ragging and the top-water.Top Water. The water, carrying fine material in suspension, which flOiWS over the surface of the jig bed.Hutch Water. The water added to the jig below the screen. (Except for the water discharged with the hutch concentrate, the "hutch-water" eventually becomes "top-water.")Feed Water. The water in the ore pulp fed to the jig.(This water becomes part of the "top-water.")Pulsion. The period of the jigging cycle during which the water is moving upwards relative to the particles in the jig bed.

Jan 1, 1937

Yallourn brown coal and its characteristics have been the subject of innumerable papers and discussions. The Lurgi process adopted for the production of Towns gas by the gasification of brown coal has been described frequently in literature.The application of the Lurgi process for the gasification of Yallourn briquettes has naturally lead to some unexpected problems. Rather than attempt to review the whole field of experience gained in the first two years of operation of the gasification plant at Morwell, this paper attempts to describe two problems encountered, peculiar to the fuel used, and the steps taken in overcoming them.THE PROCESS AND PLANTTo clarify the conditions surrounding the problems, it is necessary to briefly describe the gasification and cooling processes and plant.Brown coal briquettes are gasified in a pressure generator, using a mixture of steam and oxygen as a gasifying medium. Crude gas produced in the generator is washed and cooled in the waste heat boiler and coolers. Figure 1 shows an arrangement of the generator and coolers. The gasifying medium enters the generator through a hollow shaft in the base. This shaft drives the grate, which has three purposes: (a) to distribute the gasifying medium into the fuel bed; (b) to extract the ash from the fuel bed; (c) to support the fuel bed.Briquettes enter the top of the generator through the coal lock chamber and the fuel bed is maintained at a reasonably...

Jan 1, 1960

High Pressure Grinding Rolls Scale-Up and Experiences

Sep 13, 2010

Fragmentation Characteristics of Iron Ores from Anshan, China

Sep 13, 2010

Evaluation of Grinding Medium Wear in Stirred Mills The standard fine grinding machines in the minerals industry are stirred mills whose performance largely depends on the competency of the grinding medium. Medium wear in stirred mills is one of the key parameters for medium selection. A wear evaluation methodology is developed and applied in this paper to measure the wear rate of river sand using a laboratory batch stirred mill. The procedure is demonstrated by testing the sand medium in a 0.55 kW batch stirred media detritor (SMD). The sand wear rate determined in the laboratory batch mill is successfully scaled up to that determined on a full-scale Metso 355 kW SMD mill.

Sep 13, 2010

Geotechnical input is interwoven into the mining process at George Fisher South Mine from the planning and design of working areas to the closure of worked out areas and maintenance of life of mine and long term excavations. The methodology used consists of a mixture of application of established theoretical principles and guidelines derived from successful historical experience. In the development stage, including long term infrastructure excavations, the process takes into account the expected life of the excavation, usage and expected stress changes during its life span. On the stoping stage, the design process takes into account the local rock mass conditions, geological structure setting and previous experience in a particular orebody. Due to the high variation in age of currently used excavations, a rolling monitoring and risk assessment process for long term and life of mine excavations and infrastructure is maintained. This paper has as an output the process that must be followed to ensure an excavation on the highly dynamic mining environment at George Fisher South Mine is blasted and maintained in compliance with applicably commonly accepted safety and industry requirements.

Nov 25, 2010

A rotating disc geometry was used to provide a uniformly accessible surface for a kinetic study of copper cementation with zinc in sulphate solution. For copper concentrations of the order of 10 p.p.m., a porous, adherent deposit is formed on the zinc surface and this has a significant influence on the reaction rate. When the specific mass of deposit is less than about O· 35 mg/cm2 the surface may be considered as smooth and the rate is described by simple convective counter diffusion of zinc and copper ions through a laminar diffusion boundary layer to the deposit-solution interface. In the presence of additional deposit, the diffusional mass transfer rate is increased by increased surface roughness.The rate under these conditions is first order, with the degree of enhancement independent of further increases in the specific deposit mass. The enhancement in rateis, however, directly related to the initial mass flux and the species involved in the reaction.Preliminary work showed the same mechanism to apply to cementation from chloride solution, solutions of high zinc concentration, and cementation of copper with iron..

Jan 1, 1970

By F T. Suorineni, L Baird, A Papaioanou, D Hines

The Mathews et al (1981) stability graph was developed to provide guidance in the determination of stope sizes to control dilution in bulk mining of large orebodies. Longhole and sublevel open stoping (LHOS and SLOS) are the lower end in scale of underground mass mining with panel and block caving (PBC) at the higher end. Currently, the stability states of stopes in the stability graph are described qualitatively as stable, unstable or cave. The alternative quantitative option to the qualitative stability graph is the Equivalent Linear Overbreak Slough (ELOS) stability graph. The ELOS stability graph only applies to narrow vein orebodies. It is easy for the Mathews et al (1981) and the ELOS stability graphs to be applied outside the limits of their databases. What is currently referred to as ‘stable’ in the present stability graphs has diverse interpretations at different mines depending on their acceptable dilution values. In 2014, a research program was conceptually conceived at the UNSW Australia School of Mining Engineering to develop a quantitative dilution-based stability graph independent of orebody width to address some industry concerns on the use of the stability graphs. A dilution-based stability graph provides the mining engineer the flexibility to determine open stope sizes based on what dilution amounts are acceptable. The graph also unifies both the Mathews et al (1981) and ELOS stability graphs for wide and narrow vein orebodies, thus, eliminating their potential misapplications. To date, the concept is proven with case studies from metalliferous underground mining operations located across Australia. This paper presents the dilution-based stability graph concept, the initial results and future plans to account for other critical factors and increase confidence in its application with the addition of more data outside Australia.CITATION:Suorineni, F T, Papaioanou, A, Baird, L and Hines, D, 2016. A dilution-based stability graph for open stope design, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 511–522 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016