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By K R. Vining, T E. Norgate

A study was carried out to compare the environmental impacts of the two major iron ore agglomeration processes, sintering and pelletising, using life cycle assessment (LCA) methodology. The following agglomeration processing routes, with the fuel options shown, were investigated:sintering with combined natural gas/coke breeze or charcoal as fuel, grate-kiln pelletising with combined natural gas/coke breeze as fuel, and straight-grate pelletising with combined natural gas/coke breeze as fuel. Inventory data for each process derived from the literature, and in some instances supplemented by additional simulations and calculations, were used in the study and the environmental impact categories considered were gross energy requirement (GER), global warming potential (GWP) and acidification potential (AP). The results of the study showed that the GER, GWP and AP for a sinter plant are higher than those for a pellet plant for the same amount of metallic iron in the agglomerated products. These results are partly due to higher consumption of solid fuel and flux in the sintering process. However, it should be pointed out that the study only compared substantially fluxed sinters with acid pellets that may require additional flux (and hence potentially more greenhouse gases emissions) to be a balanced blast furnace feedstock. Extending the LCA to the blast furnace process stage was beyond the scope of the current study. Within the sinter plant, the sintering stage itself is the largest contributor to the GER, GWP and AP. In the case of pellet plant, the pellet induration stage is the largest contributor to the various environmental impacts. The GER and GWP of a straight-grate pellet plant are marginally higher than those of a grate-kiln pellet plant due to the higher electrical power required by the straight grate system. The substitution of coke breeze with charcoal in the sintering process results in an increase in GER but a decrease in GWP. However, a substantial proportion of the GER is derived from renewable sources (wood), resulting in a decrease in the non-renewable components of this environmental impact. Given the source of the inventory data and the assumptions and approximations made in carrying out the LCAs, it is emphasised that the results presented in this paper should be considered as indicative rather than as definitive results for the two iron ore agglomeration processing routes considered.

Jan 1, 2006

Treatment of Gold-Bearing Oxide High-Clayish Ores The analysis of modern state of treatment technologies of gold-bearing oxide high-clayish ores showed that the main method applied both in Russia and abroad is sorption leaching and heap leaching with preliminary granulating. The use of any of these processes depends on many factors including average gold grade, site and area of a deposit, clay content and etc. The two processes are often used at the same deposit. In this case, rich ores are treated according to a plant technology, poor ores and ores with cut-off grade are treated with heap leaching. Both technologies possess their own advantages and disadvantages. A plant technology is characterised by high recovery with higher capital and operating costs at the same time. Lower recovery during heap leaching can be attributed to an unstable quality of ore granulating due to both technological and weather conditions. In case of poor high-clayish ores, the use of a combined ore treatment is possible and profitable. It includes the ore disintegration and a clayish fraction treatment by using a heap leaching. In this case, capital and operating costs reduce in comparison with a plant technology and the recovery increases in comparison with heap leaching. Sometimes it reaches a plant recovery. These ores possess special features. As a rule, gold is associated with ore fraction, so it liberates readily from the association with ore ore-forming minerals even with relatively coarse grinding explain their high solution velocity in a hydrometallurgical cycle. Clayish ores are characterised by high sorption activity to gold cyanide complexes as well as extremely low velocity of filtration and thickening of slimic pulps at the same time. The paper describes the options of oxidised high-clayish ores treatment, such as, a plant technology (PIP and CIP process), heap leaching and a combined technology (disintegration, heap leaching of a crystalline fraction and sorption cyanidation). The obtained results were used when selecting a treatment technology and during construction of a plant for oxidised high-clayish ores treatment.

Sep 13, 2010

By A Mokhtari, S Gatehouse, N Rutherford

Geochemical exploration continues to play a significant role in new mineral discoveries inAustralia and elsewhere, including terrains where mineralisation is buried or otherwise obscured by regolith cover of various types. Transported regolith commonly restricts the migration of trace elements to surface, especially in arid terrains, presenting a range of problems for traditional geochemical exploration methods that employ surface samples. Regions dominated by transported cover include the northern parts of the Tasmanides in eastern Australia and the Yilgarn Craton which are variably covered by thick alluvium and Mesozoic to Cainozoic sedimentary rocks (Anand and Paine, 2002). An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

By Netchaef P

A rationale is presented for the use of vegetation on mine dumps to minimise runoff and infiltration which become vehicles for potential pollution. The unique topography of mine dumps promotes high atmospheric advection which leads to extraordinary energy levels for evaporation discharge - the driving force of vegetation "pumps". This effectiveness is mainly a function of how well the vegetation will grow on a given site. Recent advances in technology allow water discharge by vegetation to be measured semi-automatically, accurately and cost effectively. As a result the basis now exists for a thorough evaluation of the optimum mine dump vegetation cover. This paper presents the current status of dump rehabilitation as seen by the mining industry. The significant prospects for use of vegetation to minimise mine water related problems with subsequent savings in capital and operational cost are also outlined. However, to examine the crucial questions of optimum hydrological ability, suitability and cost effectiveness of various types of dump vegetation a proposition is made to interested parties in the mining industry: The CSIRO needs potential study sites to evaluate the hydrological ability of vegetation under mine dump conditions.

Jan 1, 1988

By A Sainoki, D Fukuda, K Shioya, C Zhang, M Sharifzadeh, T Yamaguchi, S Saydam, J Kodama, C A. Amagu, Y Fuji

In an open pit mining, ensuring stability of rock slope has been one of the major challenges. As the instability of rock slopes can results in slope failures; consequently, endanger the lives of workers, affect mining operations, and often lead to economic losses. Therefore, it is practical important to study the stability of rock slopes to ensure safe, smooth, and effective mining. The stability of rock slope of about 130 m height at Higashi-shikagoe limestone quarry, which has experienced slope failures four times since 1996, was assessed. The rock mass at the quarry is consists of mainly limestone, schalstein and slate rocks intersected by clay seams of about 70 m thick at footwall of the rock slope. Previously, the effects of limestone excavation at the foot of the rock slope and shear failure due to rainfall infiltration have been investigated. Although clay is widely known to plays a vital role in the stability of slopes in engineering projects including mines, but its impacts on slope deformation at the study quarry are not adequately examined. Therefore, the present study addressed the impact of presence of clay on slope deformation at Higashi-shikagoe limestone quarry by employing both field displacement measurements and numerical simulation. Firstly, surface displacements measured by automated polar system (APS) for over eight years were analysed to understand the overall characteristics of the slope deformation. The measured results show that the displacement gradually decreases with time. The maximum displacement of about 100 mm was observed at middle of the rock slope. Secondly, the effect of deterioration and plastic behaviour of the thick clay layer were simulated using two-dimensional finite element method (2D FEM). The simulated results reveal that the clay exhibited deterioration by water contact and plastic behaviour arising from mining activities at the footwall of the clay zone. Based on the characteristics of the measured and simulated results, it was found that the displacement induced by the effect of deterioration of clay is more noticeable at the north side of the quarry whereas displacement induced by excavation is quite significant at the south side of the quarry if clay behaves as an elasto-plastic material.

Nov 29, 2022

By B Laidens, D Souza, W Bielefeldt

The CaO-MgO-SiO2-Al2O3 system, characterised by its intricate phases and thermodynamic properties, plays a pivotal role in steel secondary refining processes, encompassing desulfurisation, non-metallic inclusion capture, and refractory protection. Accurate predictions for diverse industrial applications, including metallurgy, ceramics, and materials science, are imperative. To address this challenge, a combination of machine learning techniques will be specifically applied to model the liquid fraction of the slag and the solid fraction of MgO. The development of an artificial intelligence (AI) system, leveraging various machine learning techniques, has gained momentum in this project. The focus of this work is on constructing an AI model, based on machine learning techniques, within the CaO-MgO-SiO2-Al2O3 system, utilising simulation results from FactSage™, version 8.1 (by GTT Technologies). The primary objective is to train the AI model using these simulation outputs to predict the percentage of liquid fraction and MgO saturation based on chemical composition parameters. The AI model will undergo training with a comprehensive data set of simulations within the CaOMgO- SiO2-Al2O3 system, covering a diverse range of compositional at 1873 K. These simulations, conducted through FactSage™ 8.1 software, provide a robust foundation for AI model training, ensuring generalisability and precise predictions for the liquid fraction of the slag and the solid fraction of MgO, the solid fraction of MgO in this case is determined by the difference between the total MgO and the MgO in the liquid fraction, so it is not the objective of this study to determine which phase of MgO is in the solid state.. The predictive capabilities of this AI model hold significant implications for process optimisation, quality control, and decision-making in CaO-MgO-SiO2-Al2O3- dependent industries. Precise estimations of the liquid fraction and MgO saturation empower researchers and engineers to enhance operational efficiency and quality. This paper explores the methodologies employed for AI model creation and training, achieved results in terms of prediction accuracy, and potential applications in the field. The development of this AI system signifies a notable advancement in utilising machine learning for better comprehension and control of complex chemical systems. Furthermore, to align the study with real-world steel production, we introduce FeO and MnO at concentrations of 2 per cent and 1 per cent at 1873 K, respectively, following the validation of model results using the CaO-MgO-SiO2-Al2O3 system. This adjustment aims to bring the study closer to the observed reality in steel mills globally.

Jun 19, 2024

By BTrubT M

In the roast-leach-electrolysis process for the production of zinc, iron contained in zinc concentrates is converted to zinc ferrite during roasting. At Canadian Electrolytic Zinc (CEZinc), the Outokumpu Conversion process is used to simultaneously leach zinc ferrite and precipitate the iron as jarosite. These simultaneous reactions, while providing good process stability, require a compromise between optimum conditions for maximum zinc extraction and efficient iron precipitation. An improved conversion process has been identified which can achieve >99 per cent zinc extraction and more efficient jarosite precipitation to residual iron concentrations of

Jan 1, 1993

It is extraordinary that while Australia depends heavily on mineral wealth for its economic well-being, most Australians have no appreciation of the traditions and principles which drive and govern the mineral industry. Their understanding has been largely provided by those who campaign against the industry in one way or another and is therefore quite unrepresentative.

Jan 1, 1993

By Simpson JF, Murrie SJ

In determining new areas for slag disposal a foamed slag aggregate has been developed for use as a skid resistant material. The foaming of the slag does not rely on the use of water, but rather on the slag chemistry. Laboratory test results indicated that a product having good skid resistant properties has been prod- uced. A section of road is being assessed for performance of the aggregate in a surface dressing application under heavy load. The results from the test section after seven months have shown that the foamed slag is suitable for this application. Further test sections are now being considered.

Jan 1, 1979

By C Antonio, R Narayan, A Scheuermann, S Quintero, M Edraki, M Ziemski

Tailings are mostly loose material and can be classed as non-plastic sandy silts. They also tend to have low permeability, resulting in slow consolidation (settling) rates and low shear strength, even after consolidation. These qualities make them prone to liquefaction and, therefore, physical instability. In contrast, coarse waste rocks possess high shear strength and permeability when stacked in dumps. However, air and water flow-through the voids can cause acid mine drainage (AMD) with significant undesirable environmental implications. Combining the two waste streams before disposal by mixing presents a potential opportunity to harness the desirable properties of both waste streams. This practice is termed co-mingling and is prevalent within the coal processing industry. Co-mingling of metalliferous mine tailings is, however, a relatively new concept. By combining the coarse waste rocks and fine-grained tailings streams, the fine tailings tend to fill the voids between the waste rocks, reducing hydraulic conductivity and advective air (oxygen) flow into the rocks, thus possibly reducing acid mine drainage (AMD). Conversely, tailings are introduced to large frictional particles from waste rocks, providing reinforcement, stability, and possibly improved drainage. New separation methods are being introduced to the mining sector, which have the capacity to extract waste with significantly larger particle sizes. High Voltage Pulse (HVP) is a technology in which relatively coarse particles ranging in size from 30 to 100 mm are exposed to an electric pulse discharge. This pulse preferentially fractures mineralised particles while leaving unmineralised rock (gangue) intact. The stream can then be passed via a screen, with smaller mineralised particles reporting to the undersize and removing coarser unbroken barren particles, thereby eliminating waste. Coarse particle flotation (CPF) is another emerging new technology in metalliferous mining that applies flotation separation to coarser particles than conventional flotation. These new technologies produce different tailings (waste) streams with varying physical characteristics and possibly surface chemistries. This research aims to test new tailings mixtures by applying the co-mingling concept to blend the reject streams generated by these two technologies (HVP and CPF) with the tailings produced by conventional flotation. Combining different waste streams before disposal can improve stability and potentially reduce the acid mine drainage (AMD) rate, thus enabling early access to the tailings storage facility for rehabilitation and closure.

Aug 2, 2023

ATTENTION has recently been directed to the subject of dust production and methods of allaying same in the Broken Hill mines, so that the time would seem opportune for the local branch of the Institute to discuss certain features of an important phase of the health question in connection with underground work. Tests conducted in the Broken Hill South mine and at other mines at Broken Hill have shown that the ordinary operatioils of mining, such as boring, blasting, and shovelling, may be accompanied by the production of considerable dust unless water is judiciously used.In South Africa·dust particles under 5 microns size are regarded as dangerous, becailse they are so small as to be invisible to the naked eye, and wm esc'ape the protections set up by nature in the nose and throat, and thus may be inhaled in large quantity. A micron is 1 25000th part of an inch. This paper contains an account of the work done on the Broken Hill South mine chiefly, though some tests were done on other local mines.An acknowledgment is due to Mr. T. A. Reid, of the Broken Hill South mine, who conducted some of the tests herein mentioned, and under whose supervision most dust counts were made. Numerous dust samples have been taken by means of thekonimeter, an instrument designed by Dr. Kotze, the Government mining engineer of the Union of South Africa, and fully described...

Jan 1, 1921

The role played by lawyers in business has, in the course of the last 15 to 20 years, changed perceptively. This development has coincided with, and indeed has been a reflection of, the changing nature of Australian business, especially as the mining industry established its predominance in the Australian economy. The nature and extent of governmental regulation of business, too, has changed markedly. As a consequence, there has been a qualitative'change in the nature of commercial law practice. For the needs of business to be met, lawyers have had to develop specialist skills in new areas. Furthermore, there has been the emergence of the "in-house" lawyer, who increasingly plays a primary rather than a subordinate role in corporate law practice. There is no evidence to suggest that this trend, which is by now so well established, will prove to be ephemeral. Instead, with all indications pointing towards even greater governmental regulation of business activities, the intimate role of the lawyer in business seems entrenched.

Jan 1, 1980

ABSTRACT- I Chemotrophic bacteria, capable of oxidising inorganic species such as Fe(II) and S(-]I) for their metabolic energy, have been known for many decades and interest in these bacterial species has increased since their ability oxidise auriferous arsenopyrite ores has been demonstrated. The rate at which bacterial cultures can oxidise a solid sulphide ore is of importance but a number of difficulties arise when attempting to evaluate this oxidative activity. The two major problems are counting the number of viable bacteria present in the reactor and identifying the types of bacteria that are active in both the solid and liquid phases. Enumerating the numbers of bacteria responsible for an observed change is necessary to compare the activity of different isolates. For selection and identification of bacteria during the development stages of a project, and for monitoring an operational process, the recognition of different species will be of importance. Methods for the taxonomic discrimination of bacterial species rely on observations, different culturing techniques, and the degree of DNA base homology between isolates. A method reported recently uses IR spectroscopy for comparisons between isolates. This spectroscopic method and its application is discussed.

Jan 1, 1991

Modern technology and the need for published results have created the tendency for exploration to concentrate on drilling and assaying rather than building a broader geological understanding. Though grade is vitally important to a resource estimate, density and volume are also very important aspects that require equal consideration. Wet tropical nickel laterites are developed in humid environments over ultramafic bedrock where the nickel and cobalt are enriched to economic levels by weathering, leaching and supergene processes. These laterites often occur over rugged terrain at higher elevations where there is sufficient rain and stability for the long lateritisation process to occur. For nickel laterite profiles, the variable terrain and significant material type changes within the relatively thin profile make density and particularly volume estimation, just as significant as grade in resource estimation and assessment of resource risk. Drilling alone is generally not a cost-effective way to reduce the risk in laterite volume estimation to acceptable levels. Surface geological mapping, high resolution topographic data and other information such as ground penetrating radar (GPR) can be used very effectively to improve volume estimates. These data types are all differently structured, have different data density and quality and may potentially overlap. Integration of these disparate data types provide the most cost-effective approach to modelling wet tropical nickel laterite volumes and minimising risk. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

This paper will discuss Fordertechnik dawatering screens and their application in process industries. Fordertechnik screens were designed for the dewatering of deslimed, wet fines materials encountered in the mineral beneficiation, sand and coal processing industries. However, these screens have also been used in such industries as municipal waste treatment, paper pulp, chemicals and the food industries. Fordertechnik screens are of simple design and, as a result, offer low capital and maintenance costs. The design is based on the use of twin counter-rotating vibratory motors which provide high frequency, low amplitude linear movement of the screen deck which is essential for high production requirements. Fordertechnik dewatering screens are engineered and manufactured in Australia by Mitchell Cotts Engineering under licence to Fordertechnik GmbH of Mulheim, West Germany

Jan 1, 1984

By Walters GW

A countercurrent method of metal refining using crystallization and reflux is discussed. 4n account is given of the development of this technique for the separation of silver and bismuth from lead using bench-scale studies to the present small pilot-plant unit (around one tonne per day) in the "Commonwealth Scientific and Industrial Research Organization (CSIRO)" Division of Chemical Engineering.

Jan 1, 1975

By R Castroviejo, E Pirard, L PTrez-Barnuevo

Process mineralogy provides the mineralogical information required by geometallurgists to address the inherent variation of geological data. The successful beneficiation of ores mostly depends on the ability of mineral processing to be efficiently adapted to the ore characteristics, liberation being one of the most relevant mineralogical parameters. The liberation characteristics of ores are intimately related to mineral texture. Therefore, the characterisation of liberation necessarily requires the identification and quantification of those textural features with a major bearing on mineral liberation. From this point of view, grain size, bonding between mineral grains and intergrowth types are considered the most influential textural attributes. While the quantification of grain size is a usual output of automated current technologies, information about grain boundaries and intergrowth types is usually descriptive and difficult to quantify to be included in the geometallurgical model.Aiming at the systematic and quantitative analysis of the intergrowth type within mineral particles, a new methodology based on digital image analysis has been developed. In this work, the ability of this methodology to achieve a more complete characterisation of liberation is explored by the analysis of chalcopyrite in the rougher concentrate of the Kansanshi copper-gold mine (Zambia). Results obtained show that the method provides valuable textural information to achieve a better understanding of mineral behaviour during concentration processes. The potential of this method is enhanced by the fact that it provides data unavailable using current technologies. This opens up new perspectives to the quantitative analysis of mineral processing performance based on textural attributes.CITATION:PTrez-Barnuevo, L, Castroviejo, R and Pirard, E, 2013. New perspectives on quantitative textural analysis, in Proceedings The Second AusIMM International Geometallurgy Conference (GeoMet) 2013 , pp 191-198 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 29, 2013

Callie underground gold mine is part of the Newmont Tanami Operations, and is now the primary provider of ore to the Granites processing Mill. The Callie underground mine has produced in excess of 7.6 million tonnes (Mtpa) of ore, since production began in 1998, with a current production rate of 1.9 Mtpa. Callie underground uses sublevel open stoping with extraction through a combination of primary and secondary stopes. The primary stope filling strategy utilises cement aggregate fill (CAF) to allow full recovery of secondary stopes. The Callie backfill operation has had a continuous testing program in place during this time, which has resulted in a great deal of information available for post fill analysis. All CAF placement into primary stopes for Callie has been via surface boreholes and this has given Callie mine an understanding of some of the issues related to borehole design, type of linings to use depending on angle, depth and quantity of fill into stopes. Finally backfill barricades at Callie have undergone a number of changes during the time to optimise the design based on whether CAF or sand fill is used. This paper discusses the CAF backfill practices and testing methods used for backfilling operations at Callie.

Jan 1, 2005

Japan is the largest coal importer in the world, importing from Australia, China, Indonesia, Canada, Vietnam, etc. In Indonesia, most of the produced coal is extracted from open cut mines. More open cut coal mines will be developed to fill the demand for coal in Indonesia and the world. Many surveys and projects for developing new coal mines and transferring mining technology are being conducted in tropical counties such as Indonesia and Vietnam with the aid of the Japanese Government. It has, however, been pointed out that excessive and precarious development of mines in tropical areas will damage the environments around the mines including cultivated lands, and reduce the precious rainforest. This would undoubtedly exacerbate the instability of the global climate and the food crisis in the world. This paper describes the effects of flyash on the control of acid mine drainage in order to avoid potential negative impacts on the environment caused from open cut coal mines.

Dec 6, 2010

By A McCarthy

Spatial modelling has been used to determine potential locations of granite-related nickel skarn mineralisation throughout eastern Australia. It is believed that during granite intrusion, fluid can leach nickel from nearby mafic lithologies and combine with sulfur to form nickel sulfides. Currently exploration for this style of deposit has been limited to the region around the Avebury Deposit in western Tasmania. As the lithologies near Avebury are not unique it is feasible that similar deposits could exist elsewhere in Australia. The weights of evidence spatial data modelling technique was used to evaluate the wealth of geological data available over eastern Australia and included known economic deposits as training data to weight the themes of the model. These weighted themes were combined to create a prospectivity map showing areas favourable for granite-related nickel deposits. Several regions were identified by the model to have good potential to host nickel mineralisation similar to the Avebury deposit. These include areas located throughout New South Wales, Victoria, Tasmania, the Tasman District of New Zealand and, in particular, the Rockhampton region of eastern Queensland. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008