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Study on New Tungsten Beneficiation Technological Flow Sheet of Shizhuyuan Polymetallic Mine

Sep 13, 2010

Combined Flow Sheet for Treatment and Recycling of Municipal Solid Waste (MSW) with Complex Morphological Composition

Sep 13, 2010

By R Garzon

For resources projects with healthy net present value (NPV) and low cash flow volatility, conventional discounted cash flow (DCF) analysis will continue to provide the dominant investment decision-making criteria. However, DCF analysis can be biased because it often applies a single risk-adjusted discount rate (RADR) to compare the value of projects with different risk characteristics. Many of the difficulties with DCF modelling arise from analystsÆ inability to determine appropriate risk discounts and to estimate expected spot prices inputs for the commodities produced over the life of the project. Modern asset pricing (MAP) is a very valuable complement to DCF analysis in addressing some of these issues. Most papers dealing with MAP, however, while academically rigorous, tend not to be explicit in terms of practical application of this methodology in routine project evaluation. This paper has the objective of reviewing the MAP methodology and of demystifying its complexity, by providing a simple but realistic step-by-step evaluation of a mining project, comparing its DCF and MAP NPV values. The paper concludes that MAP provides a minimum, risk-adjusted æfloorÆ value, thus representing a valuable complement to any DCF valuation.

Jan 1, 2007

Change is inevitable but learning from change is an option. Willingness to learn is one of the first lessons that a leader must learn. Get comfortable and get left behind. I propose to outline the main social changes which are taking place and their impact on the Minerals Industry. Also the changing way we do business and what are the skills needed to manage that change and diversity. How are Associations and Institutes responding to this ever changing environment? More specifically, what is my Vision for the Institute to assist professionals to achieve greater and continuing professional excellence in their chosen professions?

Jan 1, 2000

By J Sibbel, K Goh

A key issue facing mine managers in remote locations in Australia and overseas is that of managing a fly-in, fly-out (FIFO) workforce. Current Australian research (Sibbel, in prep) indicates that FIFO employees and their families do not differ from the general population in terms of their overall mental health and the well-being of their family relationships. However, they do face unique issues/pressures associated with the lifestyle, the impacts of which are dependent on the policies and practices of the company as well as individual coping and support mechanisms. Successful management of a FIFO site and its employees therefore requires specialist knowledge and skills beyond those of a solely residential operation. The well-being of the FIFO workforce depends on both site and individual employee characteristics, and has implications for productivity and turnover, as well as safety and health. In addition, although FIFO separates individuals and their families in time and space, the interaction between work and home must be acknowledged and taken into account. Drawing on findings from recent Australian and international FIFO research (eg Annear, Poot and Kingston, 2006; Beach, Brereton and Cliff, 2003; Brereton et al, 2006; Gallegos, 2006; Keown, 2005; Parkes, Carnell and Farmer, 2005; Sibbel, 2001, 2004, in prep; Shrimpton and Storey, 1996; Storey, 2001; Watts, 2004) this paper discusses key understandings of both the positive and negative impacts of FIFO employment on employees and their families, and provides practical management strategies as an aid to the development of best practice. Individual impacts including fatigue and loneliness, as well as family issues such as communication, continually changing roles and responsibilities and the impacts of regular parent absence are key areas which can be ameliorated by appropriate management understanding and action. A flexible framework approach is presented that is suitable for a diversity of operations, including principal and contractor workforces of different sized operations.

Jan 1, 2006

By S Jahanshahi, D R. Swinbourne

The classical metal-slag-gas equilibrium technique was used to study the thermodynamic activity of cobalt, iron and their oxides in iron silicate based slags containing under controlled oxygen potential (3.70 x 10-8 to 2.95 x 10-7 atm) at 1573 K. The measured activity of cobalt oxide in FeOx-25 wt per cent SiO2 slags showed positive deviation from ideal behaviour for melts with up to ten wt per cent CoO. At higher silica contents, the behaviour became closer to ideal and in accord with previous studies on silica saturated slags. The activity coefficient of FeO in these slags had virtually no dependence on the CoO content. Partial substitution of silica by lime resulted in an increase of the activities and activity coefficients of CoO, FeO, Fe2O3 and Fe3O4. The results indicate that saturation of the slag with a magnetite phase occurs at CaO contents of five wt per cent and higher. Phase equilibria studies SiO2-FeO-Fe2O3-CaO slags containing cobalt were also carried out using the drop-quench technique. Results from these experiments confirmed the formation of a magnetite solid solution containing about three wt per cent CoO at lime contents of five wt per cent and higher at 1573 K and 2.9 x 10-7 atm of oxygen.

Jan 1, 2000

By S Henderson, J V. Lawless

The worldwide association of low-sulfidation epithermal gold mineralisation, bimodal rhyolitic-basaltic volcanism and rifting is confirmed in New Zealand. In the currently productive Coromandel epithermal-gold province reported Ar-Ar dating of adularia from low sulfidation deposits falls into two groups at 6 and 7 Ma. Bimodal rhyolitic-basaltic volcanism has been reported to be K-Ar dated at 9 to 7 Ma and 6 to 5.5 Ma. Epithermal gold mineralisation in Northland is spatially associated with bimodal basaltic-rhyolitic volcanism, with rifting cogenetic with that in the CVZ. The Taupo Volcanic zone (TVZ) is sufficiently young that the presence of a segmented rift with recent bimodal rhyolitic-basaltic volcanism can be genetically associated with epithermal gold mineralisation, which occurs as both fossil occurrences and in active geothermal fields. This reinforces the known potential prospectiveness of the Coromandel area and increases that of Northland and the Taupo Volcanic Zone.

Jan 1, 2005

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 A J. Broome

Since 2003, there has been an unprecedented growth in the demand for engineering, technical and project services in the mineral industries. This demand for services became evident in Australia earlier than many other markets and has since spread globally. This growth has created significant issues for the strategic direction and planning by the service provider. Such strategic questions include:- how fast to grow, how to recruit, train and integrate new staff, what market sectors to service, the selection of targeted customer sectors and managing strategic growth with short term demands and commercial reality. These factors are discussed using in depth experiences and examples that illustrate these strategic approaches. The relevance of this new industry environment to New Zealand services will be highly discussed.

Jan 1, 2007

The mining licence for the Macraes gold mine places emphasis on the progressive rehabilitation of the land to a state compatible with the landscape and environment that existed prior to mining activities taking place. The shallow soils and hostility of the environment dictate that choices of plant species should focus on persistence rather than high productivity, choices that are made easier by observing the vegetation patterns that have developed naturally within the area, by recontouring landforms to integrate with the surrounding countryside and the use of appropriate plants and establishment techniques.

Jan 1, 1992

By K B. Quast, A Schuurmans

Laboratory batch rod and ball milling tests were conducted on samples of Heavy Medium Separator (HMS) sinks from Renison Limited. The effects of mill rotation speed, rod volume and ball size on the resulting product size distribution were investigated. Between 48 and 69 per cent of critical speed, the product sizing distribution curves remained very similar, with a finer grind resulting from increasing the speed of rotation at constant grind time. Increasing the rod loading from ten to 53 per cent by volume caused the product size to become finer and more closely sized with a transition occurring at approximately 29 per cent. This was interpreted as a change of dominant grinding mechanism from abrasion to impact. No preferential grinding of the cassiterite was observed. The effect of increasing ball size at constant charge weight was to preferentially grind the coarser particles and generate more intermediate sized particles, whereas the product from a mixed ball charge gave a distribution similar to that obtained when a charge containing only smaller balls was used.

Jan 1, 1998

Reason Analysis of Impurity Containing and Technology Discussion of Quality Improvement for Low-Quality Iron Concentrate

Sep 13, 2010

Bioremediation of Acid Mine Water Using Fly Ash and Desulfotomaculum nigrificans One of the major concerns for the mining industry especially after the mine closure is the generation of acid mine drainage (AMD), and its discharge into the environment surrounding the abandoned mines, leading to serious environmental pollution. AMD is usually characterized by high concentration of dissolved metal ions, sulfate and low pH. The efficacy of fly ash was assessed for the removal of metal ions such as iron, zinc and copper as well as sulfate from synthetic acid mine water. Complete removal of ferric and ferrous, 80 per cent of Zn, 83 per cent of Cu and 62 per cent sulfate removal could be achieved, with a concomitant increase in the pH value from 2.3 to 7 using fly ash as an adsorbent under appropriate conditions. The free energy of adsorption of the metal ions onto fly ash was found to be negative, while the adsorption process was endothermic and adhered to the Lagergren pseudo-first order rate equation. Bioremediation studies using a typical sulfate reducing bacterium namely Desulfotomaculum nigrificans, after pre-treatment of the synthetic acid mine water with fly ash, cumulatively resulted in about 94 per cent zinc, 100 per cent copper and 90 per cent sulfate removal. The possible mechanisms of metal ion removal and sulfate reduction from acid mine water utilising Desulfotomaculum nigrificans are discussed.

Sep 13, 2010

By P Wood

Loy Yang Power (LYP) owns and operates a 2160 MW brown coal fired, base load power station in the Latrobe Valley, Victoria, Australia (Loy Yang A). It also owns and operates a brown coal mine that supplies fuel to its own power station and a nearby 1000 MW power station owned by International Power (LoyYang B). The mine supplies 32 Mt of coal per annum from an open pit, which is currently about 4 km long by 2 km wide and 180 m deep. LYP has 500 employees and a substantial amount of work is also carried out by contractors and consultants. GHD Pty Ltd(GHD) has been contracted to provide mine planning and earth sciences expertise. GHD is an international professional services company that operates globally in many market sectors including mining, industry and the environment. The company has major offices in Melbourne and also within the Latrobe Valley. This paper sets out the experiences that GHD and LYP have gained in establishing a unique alliance arrangement for GHD to provide a range of mine planning, earth science, dam surveillance and environmental services to LYP. The underlying philosophy of the alliance is to closely align the objectives of the two companies such that GHDÆs recompense for service delivery is proportional to the benefit achieved by LYPÆs business. Quality of service, whole of life costs and risk management are important aspects and are reflected in key performance indicators against which GHDÆs performance is measured. Currently GHD provide 20 000 hours of labour to LYP per annum, which are delivered by up to 120 staff who possess the required diversity of skills. The paper explains how the contract was initially let as a conventional service agreement and explains why the contract was transformed into an alliance. It then illustrates the operation of the alliance with reference to the 2006 work program. The paper concludes with thoughts on how the arrangement can be further developed for the future to the benefit of both parties.

Jan 1, 2006

By S Sabanov

Determining ventilation system model inputs from the field test work has been produced in the working oil shale mine which has been in production since the early 1970s. At this mine room-and-pillar with drill-and-blast methods are used. The mine has a complicated ventilation system to supply fresh air for the eight mining production areas on the radius of about 12 km. The main purpose of the experimental test works was to obtain data for estimation of an optimum cross-section area for a new ventilation shaft. Experimental test works included measurements of air volume and fan pressure using five different modes of intake air through the ventilation shafts system. Measurements of airway friction factors were obtained during the ventilation surveys to determine characteristic friction factors for the intake airway. The results of the measurements will be used for further air flow simulation processes required for design of new additional ventilation shafts in the oil shale mine. Results of the study can be useful in estimation of frictional pressure drop in oil shale mine conditions.CITATION:Sabanov, S, 2017. Determining ventilation system model inputs from field test work in the oil shale mine, in Proceedings Australian Mine Vent Conference 2017, pp 47–50 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

Past arguments advocating reverse circulation sampling against blasthole sampling are reviewed to present the debate under a different light. The advantages and disadvantages of each drilling method are compared, and the choice is presented as an informed trade-off between them.

Mar 1, 2010

The demand for gallium has increased significantly over the last few decades due to the expanding use of Ga compounds in the electronics industry. Because it is widely dispersed and rarely found naturally in concentrations greater than 0.1%, Ga is expensive (approximately US$500/kg) and difficult to produce in large quantities.   A previous study of metals in geothermal systems reported significant quantities of Ga present in the muds on the northeast margin of Lake Rotokawa, an acidic lake associated with a high-temperature geothermal field situated in the Taupo Volcanic Zone of New Zealand. Similar muds are present in many other geothermal fields in the zone, suggesting that geothermal muds could be a commercial source ofGa.

Jan 1, 1994

By C Skublak

The Government of Canada recently passed a new regulation to control the liquid discharges from metal mines in Canada. The Metal Mining Effluent Regulation of the Federal Fisheries Act will come into force within the next six months. As a result the Ontario Regional Office of Environment Canada has developed a compliance promotion program to accompany the new regulation. How the mines implement the regulation will be key to its success. This paper will briefly outline the components of this regulation, including the reporting structure, the discharge parameters and limits, as well as the requirement for the mines to conduct long-term environmental effects monitoring on their effluent discharge. The presentation will give a brief account of the compliance promotion program, and then focus on the spill trends from Ontario mining operations. The province of Ontario has the largest concentration of metal mining operations in the country with approximately 40 active mines.

Jan 1, 2002

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

Management of Mining Wastes in European Union and Developments in Turkey

Sep 13, 2010