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By N C. White, C M. Allen, I H. Campbell

Porphyry Cu-Mo (Au) deposits of southern and western China are localised in ancient arc environments and continental-collision orogenic belts. Despite the contrasting tectonic setting, the known deposit geology and geochemistry appears identical in both. As such, the application of existing ore deposit models to atypical collisional settings suggests that significant potential exists for future discovery of significant porphyry deposits throughout the accreted cratonic blocks of Asia. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

The concentrated efforts now being directed towards the development and application of monitoring and control techniques have now resulted in their widespread use in UK mines together with evidence of benefits resulting from their application. There is little doubt that the longwall method of producing deep mined coal will continue but will be made more reliable and efficient with the aid of control technology. The major fields of research and development work are concerned with planning and design of mines and mining equipment; management and engineering information; and automation of coalface, tunnelling and transport systems. The principal achievements now in widespread use are: the standard computer system MINOS, widely applied to mine transport, coalfaces and mine environment; extensive use of machine condition monitoring leading to condition-based maintenance; underground automation of conveyor systems and guidance systems for ranging drum shearers and boom-type roadheaders are being widely introduced.

Jan 1, 1985

By M Brooks, M Nelson

A fundamental study was carried out on super pit sulphidic gold ore to establish the most influential flotation characteristics which were subsequently used in the development of an optimum flowsheet to achieve best economical recovery of gold. In developing the flowsheet, consideration was given to existing operational constraints in the treatment of the Super Pit ore. The fundamental study also included an innovative diagnostic investigation to establish the location and value of gold in the major mineral assembly of the super pit ore from a metallurgical rather than a mineralogical perspective. This study mapped a metallurgical fingerprint of the major types of super pit ore in relation to the location and association of gold.

Jan 1, 2000

By A G. L Pratt, C Rossetti

The implementation of mass mining methods for large metalliferous deposits has led to the development and application of increasingly sophisticated automation and condition monitoring technologies in these mines. This technology aims to increase safety, equipment utilisation and monitoring of critical aspects of the underground ambient and geological environments. The communications networks required to support these aims and their associated technologies have evolved accordingly, and have done so in a demanding underground environment. The evolution of communication infrastructure for large underground mines has developed from basic analogue telephony to high-bandwidth optic fibre based systems. The latter is now the media of choice. More recently the developments in wireless broadband equipment designed specifically for underground environments have emerged to satisfy the needs of automation for mobile equipment and shaft conveyance communications. The use of internet protocols for industrial control and monitoring has led to the application of ethernet-based backbone networks as a standardised approach. There may also be a need for the integration of range of communications platforms in a mining operation to realise the full advantages offered by automation and condition monitoring technologies. As a result the design of the communications backbone networks for underground mines has started to become the domain of information technology professionals. Without these networks, the analysis of equipment utilisation is often not possible. The improvements that can be brought about by æsweating the assetsÆ and the transmission of business critical information are the most significant benefits of an integrated communications system. These benefits far outweigh the costs of strategic planning, subsequent specification and implementation of communication networks themselves. Future developments in mining systems and communications technology will continue to drive the demands placed upon communications networks as an essential mass mining infrastructure item. This paper outlines the benefits of secure high bandwidth backbone communications networks for mass mining operations and the need for a high degree of strategic thought and demand forecasting in the planning stages for these operations.

Jan 1, 2008

By G Neely

COPING WITH COMPLEXITY In every industry, and mining is no exception, plant and processes increase in complexity over time and managers and operators need correspondingly more knowledge. The mine manager has to delegate details to operators, engineers, metallurgists, accountants, safety specialists, personnel officers and the rest. Is it reasonable then, to expect the Mines Inspector to be competent to judge the conduct of all these operations against the criterion of the regulations? Obviously not, but what are the alternatives? One is a superficial inspection where the inspector goes on a hazard hunt for broken steps and missing handrails. Another is one in which an army of specialist inspectors marches on a mine, sometimes outnumbering the staff. Each is competent to assess some part of the operation and if he or she can find an opposite number among the mine staff, they can discuss details. But what good does it achieve? The system acts to remedy present defects and to make recommendations which, if only they were followed, would prevent the same things happening again. Given that this process has been going on since the first Factory Act of about 1840, how is it that there are any more defects left to put right? The answer of course is that defects keep appearing, and new defects arise as fast as the old ones are found and corrected. Further progress can only be made by preventing defects at their source.

Jan 1, 1994

The restructuring of the minerals industry has created new challenges for the design and delivery of professional development, and difficult decisions for potential participants. New technologies offer some new methods of delivery, but fall short in providing all of the benefits of face-to-face participation. This paper is intended to be a catalyst for discussion of the issues involved in delivery and participation in cost-effective, relevant and timely professional development.

Jan 1, 2000

Research programs have established the correlation between the basic mill operating parameters such as: size of crushing products, number of mill rotation, ore flow and quantity of ore in the mill, diameter of grinding media, and specific consumption of grinding media. Also, the mill efficiency has been determined in dependence of adsorption. Mathematical dependences and equations are presented in this paper.

Jan 1, 1993

The law including legislation such as the Occupational Health & Safety Act 1983 imposes stringent obligations on employers to ensure the health and safety of their employees. The use of pre-employment medical examinations is one tool that employers can use to assess the suitability of a job applicant for a particular position and protect themselves from prosecution or claims for compensation or damages.At the same time, however, legislation such as The Disability Discrimination Act 1992 (Commonwealth) ("DDA") and The Anti-Discrimination Act 1977 (New South Wales) ("ADA") affords protection to individuals against discrimination.

Jan 1, 1998

During the life of a mining project in Papua New Guinea (PNG), the greatest impact is on the people of the project area and the most intense, day-to-day contact is between these people and the project's field staff. Yet formal structures at present emphasise contact between much higher levels of national government and company personnel. Whilst understandable, this is unfortunate particularly since, given the nature of PNG politics, villagers do have a powerful influence on project success, as recent dramatic events on Bougainville have indicated. A greater role for local views and greater attention to such views by other parties is clearly required. But to achieve a successful marriage between informal village politics and the formal structures of investment procedures will require considerable patience and adjustment. This should be reflected in the cost of project development and be regarded as being as of a significance equal to that currently accorded to the technical aspects of project development.

Jan 1, 1990

By S Jahanshahi, T Norgate

In single stage copper making appreciable amounts of copper report to the slag phase. Various strategies are available to minimise copper losses to the slag. However a slag treatment stage is likely to be required in an economically viable process. A number of slag treatment process options are available and include: flotation, leaching and thermal reduction. In the design of an industrial process some type of economic as well as technical analysis of these options will be required. In this paper an outline of the techno-economic analysis procedure used to design a single stage copper making process is presented. The calculated operating and capital costs of industrial copper making processes are compared and used to determine the optimum single stage copper making flowsheet. The most economic slag treatment options is flotation of slags containing low amounts of copper.

Jan 1, 2000

The Warner Process has been devised to produce zinc metal directly from sulphide, thereby reducing the requirements for purchase of large amounts of energy in a special form. The process conditions for a practical process have been evaluated in an extensive program of research and development at the University of Birmingham. Recorded data now exists to take the process forward to commercial use within the next five years. The industrial economics have been evaluated. The cost of making zinc metal from zinc sulphide ore can be substantially lowered due to the reduced energy cost, locating zinc production in the neighbourhood of the mines and increasing ore to metal recoveries - particularly for fine-grained and pyritic ore. Integration of a Warner Furnace with a zinc mine and concentrator can result in a highly attractive return on capital Invested.

Jan 1, 1993

By Weller KR

Computer programs are described which help the metallurgist to process sample data from a plant survey; to carry out simple mass balance calculations; to present the results of circuit and equipment performance in convenient form; and to simulate the circuit response to changing operating conditions. The uses and limitations of these programs are explained by following through a case study of the sulphide flotation circuit at Cleveland Tin Ltd. The circuit was sampled, the data analysed, and some process inefficiencies established. Simulation calculations were then made to provide information on which to base decisions regarding possible circuit changes aimed at improving performance.

Jan 1, 1983

By Ross C

This paper uses the results of research trials by Landcare Research and Forest Research Institute and assessments of reclamation plantings at mines and other drastically disturbed sites to describe methods of enhancing restoration of native forests. The characteristics of mine and forest environments are compared to highlight the difficulties facing restoration and techniques which result in successful restoration are described. Selection of the most appropriate technique is illustrated by describing restoration of lowland beech-podocarp forest at a West Coast coal mine. The key to successful reclamation is to understand the factors controlling and limiting plant establishment and growth, then to design rooting media, surfaces and management regimes to create a favourable environment. This paper concludes with a summary of the planning and technical factors which are critical for successful restoration of native forest.

Jan 1, 1995

By J P. Hsi

Recent increase in the development of underground space in urban areas in Australia has included soft ground tunnel construction. The ground movements associated with soft ground tunnel construction may present risk to other existing and proposed structures in the nearby vicinity. Much experience has been gained both in the UK and Asia in recent years in the engineering evaluation of this risk. The paper presents a procedure to assess these aspects of soft ground tunnel construction with reference to recent projects.

Jan 1, 1999

By C Fenton

The mining industry is a relatively minor user of water, which has historically been largely soured from private schemes. Frequently mines are often located in areas with limited available water resources. Water reform is increasingly affecting access to water for new mining projects and mining companies are being required to consider the value of water and the implications of reliability in their planning. This paper seeks to briefly review the water reform process in Australia and how it is affecting the mining industry with reference to some recent project experience.

Jan 1, 2003

By Jin C, Shi X

The studies of pulp electrochemical flotation separation of pyrite and arsenopyrite were made from the thermodynamics, mineral natural oxidation rate, property of mineral surface oxidised material and pulp electrochemical flotation tests. The results showed that although pyrite and arsenopyrite possessed similar thermodynamic stability, significant differences of two minerals were observed in natural oxidation rate, property of surface oxidised material and its influence to dixanthogen formation on the oxidised mineral surface. Based on the non-thermodynamic differences, the pulp electrochemical flotation technology was successfully used to separate arsenopyrite from pyrite in pilot test.

Jan 1, 1993

Geosynclines have been well studied for many years, but very little has been written about the concepts of sedimentary basins in spite of the vast amount of data available. They have been regarded, perhaps, as well- understood intuitively, and therefore not worthy of study. Many of the fundamental concepts of geology were developed during the 19th Century with the construction of coal mines, canals and railways. It was a happy chance that led railway engineers in the early days to think that trains could not climb any but the smallest gradient, so, in Britain at -least, numerous railway cuttings and tunnels were made. These exposed to view and study, in a better form than Nature usually provides, a great deal of interesting geology. Because of the lack of literature about the concepts of sedimentary basins, it is not possible to be sure what the early geologists thought. It seems that sedimentary basins were regarded as recording a history of subsidence during the early stages, when a transgressive sequence accumulated; and a history of uplift during the later stages, when a regressive sequence accumulated. It seemed axiomatic that the age of folding and faulting was younger than the rocks folded or Faulted.

Jan 1, 1987

By J Ralston, R Sedev, D Fornasiero

The foam behaviour of low molecular weight polypropylene glycols (PPG) was investigated as a function of concentration and molecular weight (190 - 2000 g mol-1). For each polypropylene glycol, foam stability increases with concentration and passes through a maximum, beyond which foamability is suppressed as the solubility limit of the glycol is exceeded and droplets of glycol form. Light scattering data as well as static and dynamic surface tension results provide the key information leading to these interpretations. A maximum in foamability was observed for the PPG molecules with increasing molecular weight (caused by a change in molecular conformation at the interface). This suppresses the Marangoni effect and leads to a decrease in foam stability.

Jan 1, 2005

Traditional methods for monitoring, and hence controlling, pyrometallurgical processes rely heavily upon the skill and experience of operators. A skilled operator will usually achieve consistent, though often conservative, results, whilst an un-skilled operator will require considerable time and training to achieve the same results. Semtech Metallurgy AB have demonstrated that continuous and precise control of pyrometallurgical processes can be achieved through on-line analysis of pyrometallurgical flame off-gas using optical spectroscopy. The feasibility of the technology has been demonstrated on a large number of full-scale tests at production plants and by several commercial installations. Evidence suggests that installation of this technology, called Semtech Optical Production Control (OPC), has resulted in considerable economic benefits to the plant efficiency and asset life. These economic benefits are believed to be a direct result of improved objective on-line control. Technically the following benefits have been demonstrated: improved metal grade control, reduced metal losses, reduced processing time, and improved personnel safety. SemtechÆs OPC is a non-intrusive technology which relies on the fact that the composition of the vapour phase above a high temperature melt is closely related to the instantaneous status of the melt. This enables on-line real-time analysis of the furnace melt to accurately determine melt status and in particular reaction endpoints. Originally developed for on-line monitoring of copper converting in a Pierce-Smith vessel the field of applications for the technology is steadily growing. This paper introduces the Semtech OPC technology; discusses various applications and outlines the demonstrated benefits.

Jan 1, 2002

Late Palaeozoic and Late Mesozoic phases of widespread overprinting have obliterated most of the primary magnetization signature of the Tasman Fold Belt. Palaeomagnetic programs of a regional extent offer best prospects for identification and interpretation of such secondary magnetizations and for isolation of any remaining primary magnetization. In 1983 the BMR initiated a regionally oriented palaeomagnetic study of the Tasman Fold Belt to obtain palaeomagnetic constraints on the tectogenesis of the fold belt. Particular attention is being paid to the analysis of possible differential movements between suspect or- tectonostratigraphic terranes within the Tasman Fold Belt and the respect to cratonic Australia. Work has concentrated so far on the Cowra Trough-Molong High region of the Lachlan Fold Belt and the New England region. Pilot sampling has been carried out in the Gympie region. In addition Palaeozoic sequences are being studied from the Amadeus Basin and the Ngalia Basin to refine the palaeomagnetic reference frame of cratonic Australia.

Jan 1, 1987