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By Walker G. S

A study of the crystalline materials on or near the surface of freshly made or "green" superphosphate granules and mature, "set" superphosphate granules was undertaken using X-ray diffraction, X-ray mapping, scanning electron microscopy and electron probe micro analysis techniques. Calcium sulphate (CaSO4), calcium sulphate hemihydrate (CaSO4 1/2H20), and mono calcium phosphate monohydrate (Ca(H2PO4)2H2O), were the only crystalline species present in the "green" superphosphate.In the set superphosphate however, additional compounds were present, namely complex iron and aluminium phosphates Ca(Fe,AI) H(HPO4hF2)2H2O, (Fe)3(H3O)H8 (PO4)6H2O and calcium sulphate dihydrate (CaSO4.2H2O).The complex phosphates tied up the major part of the Fe and Al in the system and were concentrated on or near the surface of the granule. An intimate mixture of CaSO4.2H2O, and CaSO4, along with the above mentioned complex Fe-AI compounds, crystallize close to the surface of the granule and cause the setting of superphosphate that takes place during storage.

Jan 1, 1980

By P Williams

The Sunrise deposit is one of AustraliaÆs largest and most profitable gold deposits. It has consistently and spectacularly outperformed every resource model created. Currently over the life of the Sunrise pit there has been a 50 per cent under estimation of ounces mined. Without a solid basis for predicting the tonnes and grade or the spatial location of mineralisation, mine planning becomes problematic. Recently, through a better understanding of the mineralising processes the reconciliation of the resource model has improved to be in the order of ten per cent under on ounces mined. This paper will describe how the mine geologists at Placer Granny Smith have implemented the changes required to improve the resource model. Work began with the development of a three-dimensional lithological and structural model based on historical drilling and pit mapping. Continual updating of the geological model with grade control logging, assays and in pit face mapping, now allows for the on-going improvement of the resource model and the planning of mine development drilling.

Jan 1, 2000

CONTENTS:1. Introduct'iona. Previous Accountsb. Summary of Geologyc. Physiography2. Morgan Groupa. Lithologyb. Structurec. Faulting3. The Mineral Deposita. Descriptioni. Size and Shapeii. Compositioniii. Effects of Oxidationb. Relationship to Structurec. Genesis of Ored. Mount Morgan Orebodye. Sugarloaf Orebody4. Granitea. Mount Morgan Graniteb. Town Granite'c. Moonmera Granite5. Calliungal Beds6. Razorback Beds7. Acknowledgments8. References

Jan 1, 1952

Since the last occasion on which I spoke to you on this subject there has been a considerable increase in the mechanical ventilation of Western Australian mines.The following table compares the figures for 1939 with those of 1941. The type of fan most commonly used is the limit load fan. On account of its higher mechanical efficiency it has very largely superseded the multivane fan with forward curved blades.Two fans of the propeller type are in use and these have given very satisfactory service. This type of fan also has a high mechanical efficiency particularly at the correct duty for maximum efficiency.The maximum efficiencies obtainable from the various types are, for "multivane" 670/0, for "limit load" 75%, and' for aerovane 7810/0.References to propeller fans with variable pitch have appeared in the technical press, but no detailed d~scription has been issued. The advantages of these fans for mine ventilation are not obvious. An aeroplane is required to operate over a wide range of duties, while the speed of the motor for maximum efficiency is pl'actically constant. In such circumstances the propeller can be adapted to the particular work it has to do by varying the pitch of the blades. In a mine the speed of the fan can be varied to suit.the conditions, and it would appear that variable pitch is not necessary while there is a reasonable range of fans to choose from.The question of the correct position for the fan still comes in for considerable discussion. Exhausting fans at the surface have the support of time and custom, and in many cases this represents the only reasonable arrangement. Such fans should be fitted with an evase, especially in the case of fans with a high outlet velocity such as the aerovane types.It is claimed that there are advantages in having the fan at the surface where it is readily available for inspection and maintenance. Experience has shown that these advantages are more apparent than real. Fans will run for long periods with no attention other than occasional greasing and cleaning, and modern electric motors will run without attention for very long periods.In some instances the expense of a power cable to take current to the fan may be saved by placing it on the surface, but in the majority of cases...

Jan 1, 1941

By M Nehring, E Topal

Nowadays mining projects are seeking new versions of evaluation that are based on the flexibility in the project. Real option valuation (ROV) is one of the modern evaluation methods that provides a tool to adapt and revise mining projects under uncertainty and future variable movements. Most evaluation approaches simply assume that some variables are fixed, such as production rate, variable cost, fixed cost and lifetime of project. The first section of this paper reviews a comprehensive study of ROV in mining projects. The paper then introduces a new model that solves problems where previous methods lacked. The new method endeavours to find maximum mining project value by adding total cost as a function of production rate into ROV. The second section has been applied to a new model on the Century zinc mine in north-west Queensland, thus illustrating the future overview of that mine. The new version of ROV gave a significant positive value for the Century Mine, when the closure and reopening options where available throughout the life of the mine. Consequently, the new method evaluates real options to add value to mining projects, maximising projectÆs value, estimating cost function, optimising production rates and offers opportunities in projects to amplify gains or to mitigate losses.

Jan 1, 2009

Hydrogen and carbon monoxide reduction data were obtained on pelletized materials of the type currently being prepared commercially in Australia.Pellets, approximately 1 cm diameter, made from Deepdale, Iron Prince, and Mt. Newman iron ore were reduced by hydrogen over the temperature range 500°-900°C and the reduced pellets were examined by thermogravimetric, microscopic, electron probe, and x-ray techniques. After an initial time delay it was found that up to 95 per cent reduction the data could be described by a porous model where gaseous diffusion through the solid is rate controlling. Independent measurements of effective diffusivity supported the values obtained from the reduction data. Above 95 per cent reduction the rate decreased markedly due to the formation of retained wustite or fayalite.Comparison with reduction by carbon monoxide over the temperature range 750°-900°C showed that the rate of reduction was approximately five times slower than for reduction by hydrogen.The rate of reduction was found to be a function of the initial properties of the pellets which may account for the widely conflicting results that have been obtained with previous investigations on porous pellets.

Jan 1, 1971

The oxidation of sulphide minerals in aqueous suspension is discussed from several viewpoints. Limitations of our present knowledge are pointed out, and several points where further information would be of special interest are mentioned.Firstly, some properties of minerals and their effect on oxidation are discussed. Properties of different species, such as crystal structure, lattice bonding, and "metallic" properties are mentioned, and then the effect of variation within a given species is discussed. The effect of physical factors, especially particle size, is also considered. Other variables discussed include the importance of solution composition, and its effect on the nature and rate of reaction, and the use of various oxidising agents. Some factors concerned with the whole system, such as temperature, pulp density and stirring rate are then considered.Finally, the nature of various oxidation products is discussed with reference to the kinetics of reaction and the nature of the rate limiting step. It is suggested that more attention should be paid to electrochemical explanations of the reaction mechanism.INTRODUCTIONKnowledge of the factors governing the rate of oxidation of sulphide minerals in aqueous suspension is a prerequisite for the effective control of many ore treatment operations. Rapid oxidation of sulphides is usually desired during the leaching of sulphide ores and concentrates, but in the cyanidation of gold ores, or in the leaching of uranium ores, any oxidation of sulphides may be regarded as an undesirable side reaction. Knowledge of many of the factors involved is also of interest in connection with the oxidation of sulphides in flotation circuits and in natural ore forming processes.Systems for which some reasonably quantitative data have been published are listed in Table 1. Qualitative...

Jan 1, 1961

By P Wigley

New methods of analysing and modelling flotation circuits have been developed as part of the AMIRA P9 mineral processing research project. A study using these techniques was conducted on the Olympic Dam copper flotation circuit to provide the following outcomes: an estimate of the flotation cell hydrodynamic properties and froth performance characteristics, and identification of potential areas for improvement; an estimate of the feed floatability parameters for basic model development; and identification of potential flotation circuit improvement opportunities. A flotation circuit model of the Olympic Dam copper concentrator was developed using the data collected from mass balanced site surveys, along with hydrodynamic data, froth performance data and numerous laboratory batch flotation tests. The simulator that has been developed from the model has the ability to estimate the influence of selected changes (such as circuit changes) on flotation circuit performance. Several stream destination simulations were conducted to provide guidance for further testwork and possible circuit improvements. The results from these simulations are presented.

Jan 1, 2003

Some important mineral fields are referred to in discussing the formation of placer deposits in Australia.Testing methods include boring by hand, with percussion rigs, with auger and pit digging drills, and by vibro drilling.Sampling errors are minimized by the use of correct techniques and equipment for boring, sampling and sample dressing. A hypothetical set of data is used to demonstrate the final process of evaluation, and somerelevant taxation provisions are discussed.

Jan 1, 1966

The timber township of Powelltown, Victoria lies N.E. of Yarra Junction, 60 miles east of Melbourne and in the site of the mill of the Victorian Hardwood Company Proprietary Ltd.A lift gauge railway owned by the company connects Yarra Junction on the Warburton line, with the township through two or three smaller mill centres on the way.The company has been operating for some 12 years. In the divide, about four miles from Powelltown, between the Little Yarra and Latrobe rivers, cutting was continued with material being handled by winch and double incline haulage over the divide. A small bush locomotive dealt with the traffic between the divide and the cutting site.In order to reduce costs, which were heavy at the haulage, the company decided to make a continuous railway from Powelltown to the bush by means of a tunnel through the divide.Hand bore holes were put down on the proposed line of tunnel and showed that the divide at this point consisted of decomposed depth of about 100 ft. towards the eastern or Latrobe side - and that the undecomposed granite summit lay to the west of the surface summit.The bores also served to locate the underground water line, this was afterwards found to rise and fall with wet and weather.To avoid tunnelling in hard and heavy water, the grading of the was laid out with the summit of the hard granite the point in the line.

Jan 1, 1925

By J Wei, A Yo, R Levy

Waste water reuse from municipal and industrial effluents is becoming increasingly important in many areas around the world. Water scarcity, local regulation and environmental impact are driving many industries like coal and copper mines to reuse the large volume of waste water they produce. For example, the Chinese coal industry generated about 4.2 billion tons of mine waste water in 2005 of which only approximately 30 per cent was reused. Coal energy represents 76.6 per cent of the total energy generated in China in 2007 and most of the coal-fired power plants are located in north-west of China, which is a water stressed area.The selection of mine waste water treatment process is challenging as the effluents typically contains high levels of organic compounds and salinity and their composition can vary significantly. In recent years there has been a growing interest in the integration of ultrafiltration (UF) and reverse osmosis (RO) membrane technologies for mine waste water treatment and reuse.In this paper, an overview of the design and performance of ultrafiltration and RO membranes applied for reuse of mine waste water are discussed. A study was carried out in two effluents treatment plants treating copper and coal mine waste water, which are located in Chile and China respectively. The following topics will be discussed to demonstrate the performance of an integrated membrane system in mine waste water reuse: The main challenges from copper mine waste water treatment: high level of chemical oxygen demand (COD); high level of total suspended solids (TSS); high salinity; high concentration of silica, sulfate, iron and other contaminants; and fluctuation of raw water quality. The main challenges from coal mine waste water treatment: high level of total dissolved solids, and waste water quality fluctuation. Design parameters for waste water treatment systems: Selection of pretreatment for dual-membrane system in the copper mine: Clarifier with coagulation and flocculation to remove high TSS; Dissolved Air Flotation (DAF) to remove non-settling solids; Media filtration to handle fine solids and particulate organics; Activated Carbon filters (ACF) to remove dissolved organics, colour and odours. Selection of UF and RO membranes and specific design of their recovery, flux, chemical dosage and cleaning regimes. Finally, the performance of UF and RO, including the main fouling factors and efficient cleaning procedures, will be presented and compared to the design parameters to demonstrate the efficiency and performance of the selected integrated membrane systems in each case.

Jan 1, 2009

During the lifetime of an open pit mining project, each stage from exploration activities to exploitation and mine closure produces disturbances on the mining region. Mined land reclamation plans establish constructive solutions to rehabilitate the disturbed areas. Open pit mining as an effective method for exploitation of a wide range of orebodies especially for massive reserves of shallow metallic substances has exhaustive and harmful environmental effects on the mining project region. Nowadays, closure and reclamation stage in a mining project is emphatically enforced by the relevant environmental protection regulations in many countries. It is therefore obvious that closure and reclamation costs of an open pit mining project, as costs of other stages of project, must be estimated to enter the planning and design processes in open pit mining. Post-mining land use is the most important factor to recognise closure and reclamation costs. Thus, using a model to define optimal land use in planning phase of an open pit mining project is necessary in this regard. In this project a model was developed to define optimal land use regarding different sections of open pit mines such as pit(s), waste dump(s), tailing pond(s), roads, areas for onsite facilities and free land zones which are not mined. TOPSIS and PROMETHE techniques were applied to create the developed model. Lumber production was recognised as the optimal post-mining land use for the pit area of the case study in this project.

Dec 6, 2010

The relationship between the maceral composition of coal and the strength of the coke produced from that coal has received a great deal of attention in recent years.Studies using two Bulli Seam coals, and blends of Bulli and Wongawilli Seam coals, from the IIIawarra Measures of the Southern Coalfield of New South Wales were carried out.The optimum range of vitrinite was found to lie between 45 per cent and 60 per cent (mineral matter free).Above and below this vitrinite range coke strength deteriorated. Coke strength indices increased with rank, and the optimum vitrinite content increased with an increase in rank. These changes require confirmation as trends by testing a third level of rank. It was noted that vitrinite content decreased with an increase in the specific gravity of separation of the coal.Use of petrographic analyses will increase confidence in choosing coals for coking, provided the coals are well known. Such analyses offer the possibility of greater flexibility in coal purchases and the possibility of producing a marketable blend from coals, which have limited market potential. Critical base coals for blends can be conserved.Significantly more work is required before coal reserves can be utilized to optimum advantage. This work would require extension of the studies discussed in this paper and, in particular, the testing of a wider range of rank.

Jan 1, 1971

The seams of black coal occurring in Victoria are so disturbed by faulting, wash-outs, thinning, etc., that it is necessary, for the prevention of costly errors in development, that close boring be undertaken so that the correct positions of the shafts, tunnels, main and auxiliary roadways can be set out in order that the area can be economically worked. The State Coal Mine has two boring plants continuously at work, which have given good service for the last twenty-five years.The information supplied herein is merely our experience in boring at the State Coal Mine over an extended period. The type of plant in use is that known as the Victoria Drilling Plant, equipped with an 11 h.p. portable oil engine, using power kerosene as fuel. It was purchased in 1914, complete with mechanism for cable drilling, capable of boring to a depth of 1500 ft. with a guarantee of 1000 ft., with Calyx cutters, boring rods and all necessary equipment for the sum of £1473. The chief mechanical features of the plant are as follows:-The derrick is in the shape of a tripod (see Fig. 1), two of the legs being of steel channel built together to form a frame which, when lowered on to two sets of road wheels, forms a carriage for the transport of a portion of the boring equipment. The third leg is made of oregon in the form of a double bow, with bolts and distance pieces between the wooden sides. The top of this is hinged on to the steel frame, and the bottom is fitted into a cast iron block, having two small wheels to facilitate erection. A rope attached to the cast iron block and to the winch easily...

Jan 1, 1936

Removal of As(III) and As(V) in Aqueous Solution There are toxic arsenical species such as As(III) and As(V), and arsenious species have specially strong toxicity. The strong toxicity causes contamination of groundwater and water pollution for the semiconductor production process. This study is concerned with the removal of As(III) and As(V) with various kinds of Mg/Al layered double hydroxides (LDH) containing CO32-, SO42-, Cl- and NO3- as interlayer anionic species. The anion exchange property is different from the kind of layered double hydroxides and the Mg-Al-NO3-LDH is superior in the anion exchange property of As(III) and As(V) due to the nature of nitrate ion existing in the interlayer. The pH condition suitable for As(V) removal is 7.1 or more. If the initial conditions such as 10mg/dm3 of As(V) concentration, 7.1 of pH, 1 m3 of amount of solution and 99 per cent of removal are fixed, the required amount of Mg-Al-NO3-LDH is 0.27kg for two step-batch operations. The As(III) is suitable to oxidize to As(V) before the removal processing.

Sep 13, 2010

By Parker JB

The Channar Iron Ore Mining Project (the Project) is a joint venture involving the Hamersley Holdings group (Hamersley) and the China Metallurgical Import and Export Corporation (CMIEC). The Project represents the first new iron ore mine development in Australia since 1971/72 and is the first major overseas mining investment by the People's Republic of China (PRC). The Channar mine is being constructed in the Pilbara region of Western Australia and will operate for more than 20 years supplying the PRC with 200 M tonne of high grade iron ore. The Project is configured to take advantage of Hamersley's existing production and support facilities. The Joint Venturers will invest A$280 million to achieve an initial production rate of 3 M tonne/yr and an additional A$120 million over the next 8 years to achieve full capacity of 10 M tonne/yr. Financing the Project to meet the requirements of both Hamersley and CMIEC, with the dependance of the Project on Hamersley's infrastructure, and in a depressed iron ore market, required an innovative financial structure to be arranged in a limited period. This paper describes both the financial structure and its implementation, and draws a number of conclusions regarding the financing of resource projects.

Jan 1, 1989

By Narasimhan K. S, Sastri S. R

A typical high silica low grade magnesite from the Salem area of Southern India, was used in studies to develop a suitable flotation system involving commercially inexpensive sodium oleate as the collector together with other reagents which can give a product of the required grade with an acceptable recovery. It was found that the presence of metallic ions such as Cu+, Fe+++ or Ca++ introduced by the addition of their salts, or by their formation with the addition of hydrochloric acid to react with magnesium and calcium carbonate in the me, can act as effective depressants for silica. The addition of 'hydrochloric acid' was found to give best results.

Jan 1, 1980

By Xu Z, Hu C

An attempt has been made to investigate the performance of green pellet formation of the Daye magnetite concentrate from the weak-magnetic separation plant. The optimum conditions for the commercial production of green pellets was found through experimental research. The satisfactory size range for balling is 75 ¦ 3 per cent -200 mesh. The suitable moisture content is between 8.7 and 9.1 per cent and the optimum amount of bentonite added is between 1.5 and 2.5 per cent. The emphasis is on the size of the feed materials since the grinding fineness, which can be obtained at the plant, at most is 78 per cent -200 mesh. If the optimum fineness for the pellet formation is above this value, this means that the concentrate must be re-ground before balling. The results from experiments showed that a good quality green pellet can be attained by using materials below 78 per cent -200 mesh, which provides a strong foundation for the commercial production of green pellets.

Jan 1, 1999

By I Zulkarnain, H Permana, R A. Binns

Through an ambitious but relatively low-cost program of marine fieldwork, laboratory investigations and technology-transfer and training activities, three Indonesia-Australia-led marine expeditions were undertaken aboard KR Baruna Jaya VIII between 2001 and 2003. These IASSHA (Indonesia-Australia Survey for Submarine Hydrothermal Activity) cruises have sought to discover and investigate a variety of potential ore forming hydrothermal systems in a range of tectonic settings. All cruises have been successful, both scientifically and from the point of view of training, creation of capabilities and capacity building for such research in Indonesia. Over 60 scientists and technicians from Indonesian and Australian institutions and agencies have been involved. Three new sites and a possible fourth site of hydrothermal activity were discovered in the Sangihe arc in northern Sulawesi. Surveys in the Tomini basin tested a hypothesis based on previous data which suggested this might be an isolated anoxic, brine-filled basin over 2000 m deep where igneous heat sources existed to generate hydrothermal mineralisation. The bay, however, was found to be open to adjacent deep ocean circulation, and there was no evidence of massive base metal sulfides. Subdued evidence of hydrothermal activity was found in the Sunda Strait associated with the famous Krakatau volcano and the extension of the seismically active Semangko Fault. The BANDAMIN program (Indonesia-Germany) covered a portion of the Banda arc in eastern Indonesia, and also found evidence of recent hydrothermal activity and epithermal sulfide mineralisation.

Jan 1, 2004

The steps for the beneficiation of iron ores differ from ore to ore, depending on the mineralogical phases of the particular iron ore and the nature of the association of the gangue minerals with iron oxide in that ore. The extent to which the beneficiation can be undertaken economically depends both on the amount and the nature of the gangue. The analysis of the phases present in an orebody optimises the mining and process operations (separation, beneficiation, sintering, etc).X-ray diffraction (XRD) provides qualitative and quantitative information about the main ore phases as well as the gangue mineralogy and the amorphous content present in a sample. In addition, modern quantification methods such as Rietveld refinement allow the calculation of the distribution of elements in solid solutions such the substitution of Fe with Al in goethite or hematite.The use of high speed detectors has made XRD an important tool for grade and process control. Finger printing of XRD data can facilitate multi-dimensional mapping of ore deposits and drill cores, identifying regions of favourable mineral compositions. Grade control using XRD can be completely automated and controlled remotely.The two case studies in this paper demonstrate how XRD and finger printing can be used for grade control, process optimisation and quality control of a goethitic and a magnetitic iron ore. The enormous potential of XRD as an inexpensive, reliable tool, useful in the characterisation of iron ores will be demonstrated.CITATION:K÷nig, U, 2013. Application of x-ray diffraction to iron ores - potential implications for grade control and downstream processing, in Proceedings Iron Ore 2013 , pp 275-280 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013