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Removal of Thiocyanate from Solutions by Precipitation

Sep 13, 2010

By D A. Manhire, R M. Flores

The commercial develop of coalbed methane from the Powder River Basin has demonstrated that low-rank coals can be a viable source of gas. Currently over 20 000 coalbed methane wells exist in the Powder River and it is predicted that there will be 50 000 wells by 2010. What makes the Powder River Basin successful is the thickness of the coal (in excess of 30m) as well as the low ash content (

Jan 1, 2002

By E Topal

Stopes are used in several underground mining methods. Boundary determination of these stopes is generally based on simple rules of thumb. While several stope boundary optimisation techniques are available, they fail to guarantee true optimum results. The first part of this paper reviews some important stope boundary optimisation studies and proposes a new algorithm to optimise stope boundaries and layouts for underground operations. The second part applies the proposed algorithm to a block model to test its ability to produce optimum results and demonstrate its applicability in a number of different scenarios. The results demonstrate that the proposed algorithm can find optimum stope boundaries and layouts in three dimensions for different stope sizes and economic conditions.

Jan 1, 2009

By D J. Brake

The correct specification and then selection of primary or major fans for an underground mine is a critical decision not only in terms of fan capital and operating costs, but also safety and reliability which usually has a major impact on mine production. In addition, fan manufacturers may spend tens of thousands of dollars preparing proposals for a purchase enquiry for primary fans especially where they have complete responsibility for the installation (turnkey projects). There are many good reasons to thoroughly and fairly adjudicate fan tenders. This paper describes the process to achieve this starting with the initial fan specification through to the final award.CITATION:Brake, D J, 2017. Fan specification and tender adjudication for mine ventilation engineers with particular reference to turnkey projects, in Proceedings Australian Mine Vent Conference 2017, pp 245–252 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

Aurum Reef Resources is a provincially owned unlisted public company which holds a number of prospecting licences over Otago hard rock historically active minesites. The Bullendale Licence 31 1845 was applied for in 1985, granted 1991, including a DoC special condition allowing re-opening of the historic workings. The underground workings were commenced in 1862 and up to the mine's closure in 1906 some 40 000 ounces were produced at an average grade of 15.5 g Au/t. The purpose of the summer 1991 work programme was to enter the workings in an attempt to observe and sample the mullock between the lodes operated by the early miners. This objective was achieved on the third attempt. Samples were taken and subsequently a contract geologist resampled the workings and prepared a report indicating the Bullendale lode zone to be generally mineralised. Mullock interlode and schist foot-wall consistently returned assays over 0.5 g/t.

Jan 1, 1992

By R J. In, C Moore, P J. Moffitt, T Hansen

Telfer Gold Mine combines a world-class gold and copper resource and longevity of operation as a major gold and copper producer. Telfer Gold Mine has undergone a series of transformations since mining commenced as a high-grade narrow-vein oxide open pit operation in 1977. In 1986, the open pit operation converted from a narrow-vein, high-grade operation, to a low-grade high-volume oxide mining operation utilising dump leach processing technology. Mechanised underground mining of the high-grade narrow-veins commenced in 1990. Total recovered gold production between 1977 to 1999 has totalled 5.7 million ounces. The Telfer Extension Project consists of two pre-feasibility studies, the Surface Extension Project (SEP) and the I-Series Project (ISP). The combined studies represent one of the more significant resource evaluations undertaken in the gold industry in recent times. Geological activities for the SEP pre-feasibility study have included the drill definition of a large low-grade resource within an area of 25 km2 . The surface drilling program has completed 15 000 metres of HQ3 diamond drilling and over 30 000 metres of RC between last quarter of 1998 and late-1999. The ISP pre-feasibility study is currently evaluating the resource potential of both a high-grade low-volume and a lower grade bulk mining scenario, 800 m to 1200 m below the surface of Main Dome. 15 000 metres of underground diamond drilling have been completed between last quarter of 1998 and August 1999 as part of this study. Systems and cultures have been developed to maximise safety, monitor the quality assurance/quality control (QA/QC) on all aspects of the operation, and minimise impact on the environment. All data are stored in database systems, specifically designed for Telfer operations. 3D geostatistical resource estimation using ordinary kriging has been carried out for over 220 geological domains within the 25 km3 of mineralised system. Non-linear geostatistical techniques are being investigated as part of the pre-feasibility study.

Jan 1, 2000

By K Saito, M Hasegawa

In steelmaking processes, it is known that P2O5 in dephosphorisation slags often exists in solid solutions between Ca2SiO4 and Ca3P2O8, <C2S-C3P>SS, and thus the solid solutions play an important role in the dephosphorisation reaction. Hence, the knowledge of thermochemical properties, ie phase relations and activities of components, in slags containing <C2S-C3P>SS are necessary for the effective removal of phosphorus from hot metal. In this study, the P2O5 activities in <C2S-C3P>SS were measured through the gas equilibrium method. In the present experiment, oxide samples were equilibrated with Cu-P liquid alloys at 1573 K under a stream of Ar + H2 + H2O or Ar + H2 + CO2 gas mixture in which oxygen potential was fixed and then equilibrium phosphorus concentrations in the Cu-P alloys, [mass%P]Cu, were analysed with ICP-OES.

Aug 21, 2024

Determination of Porosity and its Influence on Specific Surface

Sep 13, 2010

Use of Impact Crushing for the Enrichment of Low-Grade Colemanite Concentrates This paper presents the results of an investigation into the enrichment of -25+3 mm low grade colemanite concentrates exploiting differential breakage properties of various minerals associated within the ore sample. Boric acid production process requires concentrates containing at least 42 per cent B2O3, hence concentrates below this grade either stock piled or further treated to increase B2O3 content. The low grade concentrate is obtained as a by-product of Emet Colemanite Concentrator and the B2O3 content may vary around 37 - 38 per cent. The sample used in the experimental studies assays 37.52 per cent B2O3. In the experimental procedures the sample was crushed using a laboratory size horizontal shaft impact crusher and the products were classified into different size fractions by screening so that any improvement by size could be observed. In the tests the effects of parameters such as the revolution speed of the crusher and heat treatment was checked. Test results prove that boron contents show a tendency to increase as the particle size decreases. As a result of the experimental studies a colemanite concentrate assaying 42.13 per cent B2O3 is produced with 76.55 &nbsp;per cent recovery. Arsenic content is seen to change inversely proportional with the B2O3 content of the concentrate such that it drops from 1016 ppm from the as received sample to 676 ppm in the concentrate.

Sep 13, 2010

Project Sustainability Assessment - Matching Method to Enterprise Size Sustainable development requires managing natural resources, including minerals, in a way that is conducive to long-term wealth creation and the maintenance of capital (natural, social, human, economic and physical). One aspect of the minerals sustainability discussion focuses on replacing depleted mineral capital with other forms of capital so as to ensure that the contribution of a mineral project is net positive over its life. Another, equally important, aspect focuses on selection of projects and technologies that contribute to the achievement of a variety of sustainability objectives, such as environmental protection, efficient use of resources, water and energy, worker health and safety, and the equitable distribution of risks and benefits within and across generations. Technical feasibility and relative economic performance remain necessary decision criteria for mineral investment decisions, but they are no longer sufficient. Enterprises, regardless of size, are now confronted with the challenge of comparing investment alternatives based on a new, broader set of criteria. The field of integrated sustainability assessment (ISA) emerged in response to this changed social and business environment. ISA is a structured process for examining the economic, social and environmental impacts of a project or technology. The purpose of an assessment can be broad, a strategic review of corporate behavior for example, or quite narrow, input to a specific decision process such as the selection of a piece of equipment. There are numerous methods and analytical tools available to conduct ISAs and selection of the most appropriate for a given situation will depend upon temporal focus (retrospective to prospective), decision context (strategic, tactical or operational), and phase of the assessment process (problem structuring, analysis, resolution, ex post review), among others. Selection also depends upon enterprise size and the attendant availability of financial and human resources. Large multi-national firms often undertake complex, data intensive sustainability assessments, in part because the projects they are involved in are multi-faceted, long term, and require significant financial investments. Small and medium sized enterprises are seldom able to commit the same level of resources to an ISA, and if the projects they undertake are less complicated, a time consuming and detailed assessment may be unnecessary. Regardless of enterprise size, the tangible and reputational benefits of conducting as ISA must exceed the actual monetary cost of doing so. This presentation will provide an overview of available ISA tools, categorising them in terms of their data requirements, methodology, outputs and applicability in various decisions contexts. Distinction will be drawn between situations where reasonable approximations of project impacts can be expected to provide an adequate amount of information and those for which more detailed analysis is essential. Finally, ISA strategies that have been successful and cost effective at different scales of business enterprise will be identified. This is an abstract only. No full paper was prepared for this presentation.

Sep 13, 2010

By N Currey, G W. Wilson, P Ritchie

Kidston Gold Mine in Queensland, Australia has a 310 ha tailings impoundment that has undergone final closure rehabilitation. Kidston Gold Mine evaluated their closure options for this low acid generating tailings impoundment, and due to a lack of cover soils and the cost of importing material, the mine decided to investigate the possibility of direct vegetation onto the tailings impoundment surface. The mine subsequently embarked upon a well planned and detailed research program to determine the feasibility and sustainability of this closure option. The research program included vegetation trials, toxicology studies for metal uptake by vegetation, as well as a comprehensive closure water balance model for the tailings impoundment complex. This paper describes the results of the long-term closure water balance for the tailings impoundment complex for the pre-closure state of the impoundment, as well as predictions towards the impoundment performance once final rehabilitation of the tailings impoundment complex has been achieved. The water balance presented is unique in that it is founded on unsaturated flow principles and accounts in full the impacts of the surface flux boundary conditions. This novel approach enables the prediction of actual infiltration rates into the tailings impoundment surface, which in turn allows for the calculation of how much seepage will exit from the tailings dam toe drains.

Jan 1, 2003

The emerging coal seam gas (CSG) industry has the potential to provide a large-scale energy province for Queensland. Aquifer impacts and management of associated by-product water, both in terms of quantity and quality, are pivotal considerations for the development of a sustainable CSG industry.Legislative changes have been introduced to ensure that the CSG industry manages potential groundwater impacts and beneficial reuse of the by-product water to a level acceptable to both government and the community.The relevant new pieces of legislation covering petroleum and coal seam gas activities include the Petroleum and Gas (Production and Safety) Act 2004 (P&G Act), Petroleum and Other Legislation Amendment Act 2004 (POLA Act), the Petroleum and Gas (Production and Safety) Regulation 2004 and the Petroleum Regulation 2004. Other relevant legislation includes the Petroleum Act 1923 (Petroleum Act) and Part 7AA of the Mineral Resources Act 1989 (Coal Seam Gas Regime). The P&G Act introduces a full regime for managing water rights. This includes provisions for monitoring and reporting on the effects that the taking of underground water under petroleum tenure has on other bores in the area. The P&G Act also imposes a æmake good obligationÆ on petroleum tenure holders, which requires the restoration of bores affected by the taking of water or the payment of compensation. These provisions represent a significant departure from the Petroleum Act, which says very little about water rights and does not specify restrictions on the taking of water under petroleum tenure. This paper attempts to outline the requirements and obligations of the P&G Act for the CSG industry in terms of underground water rights, development impact assessments, aquifer trigger thresholds, monitoring and reporting requirements, as well as the make good obligations.

Jan 1, 2006

Pressure Oxidation of Sulfide Gold-Bearing Concentrates with Double Refractoriness

Sep 13, 2010

The relationship between comminution testwork results and the milling circuit that is subsequently selected is not a direct one and frequently involves recourse to databases of past test results. This in itself reflects the lack of a systematic engineering approach in the design process. This paper reviews comminution tests for SAG mill design in an attempt to identify where the essential information comes from that will be used in mill selection. The conclusion is that results from traditional test methods, including obscure and little used procedures like the Mokken test, are more valuable from an engineering perspective than parameters for breakage rate based modelling. Suggestions are made on ways in which existing test procedures can be enhanced in order to generate parameters that can be directly related to characteristics of the milling circuit being designed.

Jan 1, 2002

Investigation of the Effect of N-Substituents on Performance of Thioureas as Special Collectors for Copper Sulfides by ab Initio Calculations

Sep 13, 2010

It has been thought in the past that New Zealand had ample coal reserves, able to provide fossil fuel supplies well into the future. Such is not the case and every effort must be made to achieve the highest possible extraction rate in all new coal mining ventures. While the relative cost and availability of completion or fuels has been largely responsible for the slow growth of coal production in the past, a world shortage of fuels has given coal a new importance and required better utilisation of coal reserves. New mining ventures in thick-seam coal deposits cannot be planned and designed without geotechnical investigations designed to provide information required by the mining engineer and analyst. Finite element analysis of mine workings may provide essential information on the optimisation of mining techniques and the design of underground support and roadway shapes.

Jan 1, 1976

By A Bouazza, J Kodikara

In this study, 23 samples of leached ash (LA) were collected from an ash pond at Loy Yang Power Station and geotechnically characterised. The samples were collected at various depths and locations within the ash pond on two separate occasions in order to account for the full variability. The LA within the ash pond at Loy Yang Power Station (LYPS) was found to vary in texture from silt to sand, depending on the location from where the sample was collected. Samples collected near the ash pond inlet discharge point, for instance, contained more than 50 per cent sand sized particles and were subsequently classified under the Unified Soil Classification System (USCS) as silty sand (SM). Further downstream of the inlet discharge, the LA became progressively finer and was classified accordingly as elastic silt (MH) when the sand content became less than 50 per cent. Basic geotechnical testing revealed that the LA from Loy Yang Power Station was generally acceptable as a landfill cover material. The permeability of LA, however, was generally too high for prescriptive covers, (ie resistive covers that generally rely on the impervious nature of the material to control percolation). Alternative covers, generally rely on the store/release function of a capillary or monolithic barrier to prevent percolation into the landfill. Subsequently, a material that can maintain a high water storage capacity while at the same time, readily allow infiltration and evapotranspiration is required for an alternative cover. Sandy silt and silty sand are optimal soils for alternative covers, as they do not yield water to gravity forces, but do give up most of the water in their pores when subjected to high-matric suction (Kavazanjian, 2001). The effectiveness of alternative covers is ultimately assessed using computer models, such as UNSAT-H and HYDRUS-2D, to rigorously perform water balance calculations. Prior to using a computer model to determine the highest possible percolation in the worst climatic conditions, it is necessary to select the most appropriate materials. This paper suggests a method to screen available materials for use as an alternative cover material on the basis of the soil water characteristic curve (SWCC).

Jan 1, 2003

By Y Xie, D Willingham

Predictive maintenance (also known as ‘condition/health monitoring’) refers to the intelligent monitoring of equipment to avoid future failures. In contrast to conventional preventive maintenance, the maintenance schedule is not determined by a prescribed timeline; instead, it is determined by analytic algorithms, such as machine learning, using data collected from equipment sensors and/or via simulation.Predictive maintenance offers the following benefits for operators and equipment manufacturers:- reduces equipment downtime by identifying issues before failure, thereby enabling convenient scheduling of equipment service and extending equipment lifetime- determines the root cause of the failure, enabling appropriate service to be performed without utilising resources to determine a diagnosis- avoids the unnecessary costs of maintenance and unexpected failures- improves safety and product quality.Algorithms and data are critical to predictive maintenance success. Sensor data is first preprocessed using advanced statistical and signal processing techniques; it is then combined with predictive modelling techniques, such as machine learning, to estimate equipment health.Once tested, predictive maintenance algorithms may be used in an operational setting within an IT environment, such as a server or cloud. Alternatively, algorithms may be implemented in an embedded system directly on the equipment, allowing for faster response times and significantly reducing the amount of data sent over the network.CITATION:Willingham, D and Xie, Y, 2017. Predictive maintenance modelling for bearing-based equipment, in Proceedings Iron Ore 2017, pp 627–630 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By J Zhou, D M. Hunter, S M. Iveson, K P. Galvin

The REFLUX Classifier is used to perform particle separations on the basis of density utilising a set of parallel inclined channels positioned above a vertical fluidised section. In continuous mode, feed enters part way up the vertical section, while fluidisation water is introduced from below. Lower density particles are conveyed upwards and collected in an overflow stream, while high density particles segregate onto the inclined surfaces, settle to the base of the system and empty via an underflow stream. Pressure transducers are used to measure the suspension density in the vertical section. This suspension density is maintained by a pneumatically controlled underflow valve to maintain a target suspension density or ‘set point’.Previously, Galvin et al (2010) demonstrated the significant improvement achieved via a new laminar-shear separation mechanism, achieved by utilising closely spaced inclined channels in the REFLUX Classifier. For the separation of low-density coal particles from mineral matter, a channel spacing of 6 mm proved effective; however, for the separation of gangue minerals from much higher density minerals such as iron ore, the shear-induced lift needs to be even higher. In this paper, we examine the influence of two different channel widths on the continuous processing of an industrial iron ore feed in the REFLUX Classifier. It was found that when moving from 6.0 mm to 3.0 mm channels, the ability of the system to reject coarser gangue material and retain finer high density material across a particle size range from 0.125 to 1.0 mm was increased, resulting in a higher grade product.CITATION:Hunter, D M, Zhou, J, Iveson, S M and Galvin, K P, 2017. Influence of shear rate on separation of iron ore fines using the REFLUXTM Classifier, in Proceedings Iron Ore 2017, pp 205–210 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

The Australian mining industry faces skills shortages across a broad spectrum of disciplines and levels, as it enters another major growth phase. Critical amongst the areas of most significant shortage in the professional sphere is the discipline of geotechnical professionals. More mines, deeper mines, ageing workforces are all contributing to this chronic shortage. But the shortage is not just at the operating sites, it is across a range of employment fields including sites, head offices, consultants, researchers and educators. This paper reviews the status of a number of these fields and explores some of the issues being faced. The different roles of a site geotechnical professional and a specialist geotechnical consultant are explored, together with some of the trends in terms of how such people are operating, and the skills they are expected to have to fulfill their job requirements. The paper also considers the move towards possible mandatory statutory geotechnical positions at mine sites and some of the implications if this were to come into force. Finally, the paper considers the current provider programs for mining geotechnical education, and how additional offerings are going to be needed in order to address the current shortages and the inconsistencies in terms of job expectations for people assigned to geotechnical roles without adequate education and training.

Nov 25, 2010