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By Forster G, Datta P. K

Many high temperature industrial processes involve gaseous halogen-bearing environments. Essentially, these fall into three subject areas: power generation, waste incineration and especially extractive metallurgy. Fundamental to any understanding of the process chemistry and efficiency in the process technology is an adequate knowledge of background thermodynamics relating to metal-chlorine reactions. In this context, existing free energy/temperature diagrams for metal chlorides do not include many elements, in particular the so called refractory elements from Group V and Group VI of the Periodic Table, namely niobium, tantalum and vanadium, and molybdenum. This paper reports estimation and calculations of the free energy values for these chlorides. The data is discussed in the context of high temperature chlorination processes.

Jan 1, 1991

By Shugen T

Due to the increase of passenger traffic, a new station is proposed which is about 6.8km from south station. An underground connection line is under feasibility study for connecting these two stations in order to avoid the in- terference with surface traffic. In this paper the traffic condi- tion and the geological formation along the planned route will be described and analysed. Different methods of con struction have been proposed and dis- cussed such as shield method, slurry wall method etc. In this paper compari- sons are made among these methods and advantages and disadvantages given. The authors proposal to construct this connection line by NATM raise wide

Jan 1, 1987

By Proffett JM

Batu Hijau is a calc-alkaline, island arc porphyry copper-gold deposit located in the southwest corner of Sumbawa Island in the Banda archipelago of southern Indonesia. Proven and probable reserves are 913 million tonnes at an average grade of 0.53 per cent copper (10.631 billion pounds Cu) and 0.41 g/t gold (389 tonnes Au). Construction of the deposit infrastructure began in October 1996, and formal approval for the project mobilisation was granted by the Indonesian government in May 1997. Preoperational testing and start-up of the first grinding line is scheduled for mid-year 1999.Copper and gold mineralisation are genetically related to at least three tonalite porphyry dykes and small plugs which intrude a quartz diorite stock that was emplaced into andesitic to dacitic pyroclastic rocks and lava flows. Faults are uncommon, and where they occur they do not significantly displace hydrothermal alteration and mineralisation zones.

Jan 1, 1997

By Ellson I. G

Advantage has been taken of the need to build the new mining town of Shay Gap to incorporate a new standard of living in an isolated area, which suffers from climatic extremes. The various problems associated with living in the Pilbara area of Western Australia are outlined, together with their effect on the design of Shay Gap.

Jan 1, 1973

The resources industry is unique in that the finite nature of resource deposits requires a participant to be constantly locating and developing new ones to replace those that are depleted. An effective growth strategy that enables new project developments to be brought on line in time and within budget is therefore of fundamental importance to any mineral resources company. This paper seeks to identify the role of the development project in the company's overall growth strategy and the key performance criteria that a development project must achieve in order to allow a company to meet its growth objectives.

Jan 1, 1997

The relationship between the permeability of coal to a mixture of methane and carbon dioxide, and the permeability to methane and carbon dioxide separately is described in this paper, along with the analysis of the differences in permeabilities of coal to methane and carbon dioxide.

Jan 1, 1989

By Sillet R, Corin P. J, Wilson G

Zinc Corporation of Broken Hi11 had some long hole stopes coming into use which could not be mined using diesel loaders, because of ventilation restrictions. In preference to use of pneumatic loaders, and because there were no field proven electric loaders in Australia, Horwood Bagshaw Ltd., were commissioned to repower a diesel loader with an electric motor, within the confines of the existing machine

Jan 1, 1977

By Pease JD

This paper reviews the changes in operating practices made in the heavy medium plant to meet the objectives of increased silver, lead and zinc production at lower operating cost. The effects of medium quality, screen- ing efficiency, medium consumption, equipment service life and plant availability on these objectives are described.

Jan 1, 1988

By F Cesnik, P Griffin, S Green

In July 2004 a flotation concentrate regrind circuit was commissioned in the æHigh GradeÆ Ridgeway concentrator at NewcrestÆs Cadia Valley Operations. This was the culmination of two years of project testing, process design and planning which commenced shortly after commissioning the concentrator in March 2002. During the two-year project evolution alternative grinding technologies were evaluated from conventional ball milling through to sand milling. A Detritor mill was eventually selected for the duty and the criteria on which this selection was based will be presented. As the project evolved so too did the equipment sizing with the concentrator quickly exceeding design capacity of 4 Mtpa and currently averaging 5.6 Mtpa, the process design had to accommodate this and future potential throughput increases. This paper will focus on the supporting testwork, circuit surveys and concentrate properties which were used as the design basis for the project. The economic evaluation which led to the project receiving board approval in November 2003 will also be presented. Detailed design and construction management issues will be discussed as will preliminary results and findings up to November 2004.

Jan 1, 2005

By P Elliott, D Pershke

In a minerals processing context, sustainability is about using natural resources more efficiently to achieve maximum economic benefits with minimal environmental impacts. It embodies five overarching themes, which the paper will illustrate with practical examples from Australian minerals processing plants. These are:resource utilisation and materials efficiency,process waste reduction and enhancement of co-product values,reduction of water use and impacts,reduction of energy requirements and greenhouse gas emissions, andenhanced control of minor elements and toxic materials. Sustainability could be embedded profitably in minerals plant design in three dimensions: 1.technology,2.design, and3.operations. This presentation discusses a set of principles that could be applied to minerals processing technologies and provides an outline of sustainability assessment and opportunities evaluation tools. The application of the tools is illustrated through a case study by analysing a suite of nickel processing technology routes. The analysis reveals that current generation of nickel processing technologies do possess real potential to emerge as sustainability champions in integrated processing of nickel ores and concentrates, if they are designed, engineered, and operated for sustainability and adapted effectively to site specific constraints and opportunities. The paper will address data gaps and uncertainties regarding the impact of scaling up of pilot-plant performance, and provides strategies to overcome them.

Jan 1, 2006

By B Huls, B E. Smith, I Brake, M Yu

A brief outline of some of the pioneering events in the development of flotation technology, which originated in Broken Hill at the start of the 1900s, is presented. The development of the original Potter-Delprat process, the introduction of oils to generate froth flotation and the achievement of selective flotation processing are described, all focussed on solving challenges with the Broken Hill Pb-Ag-Zn ores. Some recent initiatives in flotation at BHP Billiton operations are also outlined, covering coal, copper, lead-silver-zinc and diamonds. Some views are offered on the characteristics of innovation in flotation and on possible trends into the future.

Jan 1, 2005

By Hefter G. T, Singh P

The use of sulphur dioxide (SO2) as an anode depolarizer in place of traditional oxygen evolution reduces the energy costs of copper electrowinning. This paper reports the effect of various metal ion impurities, which are usually present in th

Jan 1, 1998

BECAUSE of the attention given in recent years to the flotation process, there is an extensive range of equipment available to any staff detailed for: the design of a flotation mill. This statement applies not only to the flotation machines, but also to equipment for crushing and grinding, elevating the pulp, dehydrating of concentrates, and the methods of driving the various equipment.Distributed through the Proceedings and Transactions of various metallurgical societies and journals there are many excellent descriptions of flotation mills, their equipment and performance.Whilst these articles describe-in many cases in detail-the equipment in the mills to which they refer, the reasons which govern the choice of each particular equipment are not usually given.

Jan 1, 1929

By Upfold RW, Nguyen VU

The extraction and utilisation of metals and materials is the basis of modern civilisation, and will remain so for many decades, Traditional metals are facing some challenges and research is needed in specific areas, to improve metal extraction processes, to develop processes for newer metals and minerals, and to develop new applications, The shortage of metallurgists now becoming apparent in Australia is a further significant problem that needs urgent attention, and much more publicity is required for the Mineral Industry, as well as for the utilisation Industries,

Jan 1, 1986

The importance of good winding rope practice is stressed. Details of the ropes used for various duties in the four shafts of The Zinc Corporation, Limited (ZC) and New Broken Hill Consolidated Limited (NBHC) are given. Inspection, testing (including non destructive methods), maintenance and rope discard criteria are discussed. There are sane catments about rope installation methods and an appendix is included which outlines the appropriate statutory requirements for winding ropes in New South Wales (NSW).

Jan 1, 1983

Maintaining and improving the economics of open pit mining in the future requires understanding of the characteristics of open pit mining that are different to other mining or business activities, designing mines in the first place to be less susceptible to changes in these important characteristics, and adopting strategies which yield reliable returns despite unforeseen change. Planning and production personnel require guidelines and performance standards that are based on sound economics not solely on production criteria. The guidelines adopted for long-term implementation must assume a declining price for mineral products along with declining real costs, with research efforts directed at development of both evolutionary and revolutionary ideas aimed at implementation. Decision-making must focus on risk and probability criteria rather than just simple return-on-investment criteria, and the approach for management of personnel must support the higher level of communication essential for fast decision-making in the new environment of continual change.

Jan 1, 1992

By G W. Wilson, C Panidis

Potentially acid forming (PAF) waste rock contained in dumps formed as a result of open cut mining of metalliferous orebodies are conventionally sealed or covered using a near-saturated, low permeability compacted clay layer, protected with a mulch layer and/or vegetated growth medium. The purpose of the compacted clay layer is to limit oxygen diffusion and the infiltration of rainfall into the dump. Where the aerial extent of the PAF waste rock dump is large, or where suitable clayey material is in short supply, it may be difficult to source sufficient suitable clayey material to form the cover. The paper describes a laboratory-based investigation of combining inert waste rock and tailings to form an alternative seal or cover material. The inert waste rock was sourced from the trafficked surface of a non-acid forming (NAF) waste rock dump, with a maximum particle size of about 100 mm. This was combined with NAF thickener underflow tailings slurry in various mass ratios, and the resulting mixtures tested for their particle size distribution, compaction characteristics, soil water characteristics (relationship between suction and volumetric moisture content), and saturated hydraulic conductivity. The mixtures tested ranged in consistency from those dry enough to be compactable, to those with the consistency of wet concrete that lend themselves to placement without the need for compaction. The laboratory test results showed that the suitability of the mixtures as seal or cover materials is very dependent on the particle size distribution of the mixture, with well-graded mixtures having substantial fines performing best.

Jan 1, 2003

By Gillies A. D S, Lee A. H

The major operational objectives of a mine water resource management system (WRMS) are to supply the water needs of the mine and mill, to minimise disturbance to mining due to rainfall flooding or seepage and to dispose of excess water. Historically, company management have placed a significantly lower emphasis on managing the WRMS as compared to managing production. Changing Government legislation concerned with the disposal of water from mine sites is, in many cases making mining companies look more closely at how they manage their water. For example, within the next few years it is likely that prior to mining approval by the Government, mining operations will have to submit water management plans/budgets and contingency strategies in addition to operational plans. While the formulation of a comprehensive water management plan/budget is an additional cost to the company at the mine establishment stage, such plans can be beneficial to the operation in the longer term.The two keys for the efficient design, operation and development of a WRMS are the establishment of written goals which have managerial priority and secondly, access to appropriate good quality data. Managerial priority towards the WRMS will increase as a consequence of the education of mine operators in the benefits to the operation of good WRMS management or less desirably as a requirement to meet Government legislation. The collection of appropriate WRMS data is a more complex issue and to obtain information efficiently and cost effectively relies on the clear definition of the data application.

Jan 1, 1992

By McNabb K. E

Significant coal reserves in New South Wales lie under areas with steep topography such as valley slopes and cliffs. Subsidence predictions are difficult to make for these locations as existing empirical databases cannot cover all permutations of topography and mining geometry. Two dimensional numerical model alternatives are of limited applicability. Consequently a novel three-dimensional numerical model is developed including the detailed panel layout, realistic rock mass properties including the full stratigraphy, goaf behaviour and actual surface topography. Model results show the same trends as subsidence measurements from Baal Bone Colliery in the Western Coalfield of New South Wales.

Jan 1, 1992

Commencing early in 1975, Saraji Mine in Central Queensland will product 3.56 million tonnes in the first year and then 4.57 million tonnes annually for the Japanese and European markets. The coal will be mined from a series of pits separated by corridors which will be mined at a later date. Through the corridors flow regional drainage structures and power lines. Relatively easy areas will be mined initially to assist the cash flow and to minimise start-up difficulties. For ease of scheduling it is desirable that pit lengths exceed 3 000m but this will not always be possible. Ramps were designed using 1 200m spacing and 5 per cent gradient as optimum but modified to suit specific conditions. One ramp will be in the end of each pit nearest the ROM hopper and stripping will commence from this end. The advantages so gained are shorter haul distances, immediate access to the coal after stripping and simplification of the excavation of the first ramp. Haul road location was defined by the minimum present value of construction plus operating costs. Road design utilised airfield construction charts because wheel loads were outside the range of available road design manuals. Low load resistance characteristics of

Jan 1, 1974