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By Whiten W. J

The control of mineral processing plants incorporates a number of off-line and on-line actions by plant personnel to obtain satisfactory plant performance. In general, off-line actions centre around intensive data analysis, while on-line activities are either automated control actions or prompted by qualitative interpretations of quantitative and qualitative information. Data sets obtained by various data logging devices and laboratory analysis of samples in many modem plants may be very large and are often unmanageable. This paper presents a method of analysing the data sets typically found in mineral processing, based on cluster analysis. The results of this analysis leads to a more complete understanding of operations in comparison with existing analysis tools used in mineral processing.Improved process configuration, optimised control strategies and in some cases, direct use of the results in monitoring process unit operations may be achieved.

Jan 1, 1992

In recent decades the awareness of environmental issues by the general public has developed at an accelerat- ing rate. This is the result of a number of factors including more scientific knowledge of environments and of the impacts of modern society upon them, higher levels of education, the opportunity for people to travel more, and the success of the various communication media in bringing in- formation to the communities of the world about such environmental crises or threats as the smogs of Los Angeles and London, the Torrey Canyon and Santa Barbara oilspills, Minamata disease in Japan, the spread of the Crown of Thorns starfish, the disposal of toxic industrial wastes into the Upper Rhine, the discovery of high mercury and zinc contents in marine foods in southern Australian waters, and the proposal to mine limestone at Precipitous Bluff in Tasmania.

Jan 1, 1975

In recent decades the awareness of environmental issues by the general public has developed at an accelerat- ing rate. This is the result of a number of factors including more scientific knowledge of environments and of the impacts of modern society upon them, higher levels of education, the opportunity for people to travel more, and the success of the various communication media in bringing in- formation to the communities of the world about such environmental crises or threats as the smogs of Los Angeles and London, the Torrey Canyon and Santa Barbara oilspills, Minamata disease in Japan, the spread of the Crown of Thorns starfish, the disposal of toxic industrial wastes into the Upper Rhine, the discovery of high mercury and zinc contents in marine foods in southern Australian waters, and the proposal to mine limestone at Precipitous Bluff in Tasmania.

Jan 1, 1975

A large scale distributed process con-trol system has been successfully applied to the automatic control of aluminium reduction cells at Boyne Smelters. A three stage hierarchy of minicomputers and microcomputers is used to continuously monitor and control conditions in each cell and to manage the data generated during the process.The automation hardware was purchased on the basis of low cost, high reliability, prior use in the aluminium industry and a high level of backup under failure conditions. The hardware has met performance criteria to date.The process control strategies have continually been updated to minimise the energy and raw material consumptions in each cell. A major change to systems software has recently been made to decrease the development time for-future changes. Various low energy potline retrofit alterations are currently being investigated requiring significant changes to the process control strategies.

Jan 1, 1985

By McCarthy PL

Widespread interest in reopening Victorian gold mines, regenerated by increased gold prices, has highlighted the technical problems prevailing. A combination of historical lease legislation, minimal recent mining activity, forms of mineralisation, high insurance rates and tortuous approval requirements for mining mean the potential investor assessing an old mine must address a wide range of technical problems. The requirements for establishment of ore reserves and attraction of capital for mine development are fundamental. Underground reef mining was historically generally on a small scale, and as mining on many fields ceased about the turn of the century, past geological and production records cannot be correlated to personal experience and comment. The impact of modern mining technology on future reef mining will be to reduce operating costs and significantly improve historic metallurgical recovery. Roth these are commensurate with increased capital costs. Workers compensation rates currently applicable in Victoria are many times higher than in other states, adding significantly to operating costs. Establishment of a pilot plant testing facility in central Victoria would provide an invaluable service in treating bulk samples essential for grade and recovery assessments of Victorian ores.

Jan 1, 1982

The paper describes the progress made in the last decade with the introduction of comprehensive monitoring of the mine atmosphere into U.K. collieries. Brief descriptions are given of the various portable and fixed point instruments which have been developed for this purpose and the methods available for transmission of information to the surface are also discussed. The paper also outlines some of the research work being carried out both in the laboratory and underground on the development of alternative methods of fire detection. Some of the results from this work are illustrated and discussed.

Jan 1, 1981

Geomorphology is one of the most basic elements in geographic enviroments. Geomorphological mapping is significant in the spatial distribution of representing land form and understanding various features of geomorphology. Geomorphological mapping began very early in China, as the map, showing conekarst(karst pinnacles) of Juiyishan, Hunan province, it was drawn in 168B.C., which was excavated from Han tomb. Mawangdui, Changsha. Its original idea of map-making is rather similar to that of modern map and could undoutedly be the oldest map of tropical karst discovered in the world.Before liberation, landform mapping was done piecemeally and only a small number of maps were prepared by a few editor as insets.

Jan 1, 1990

Grinding is probably the single unit operation that requires the largest capital investment and operating costs in an ore beneficiation plant. Because of that, a great deal of research has been concentrated in the theory, design and operation of grinding equipment, in particular ball mills. To-date, the models developed to describe grinding in tubular mills are macrophenomenological and can be divided into two categories: energetic and kinetic models. This paper presents a new approach to modelling ball mill grinding: The Operational Model. The theoretical aspects of the model as well as a comparison with existing ones are discussed. The concepts of the model, summarised in easy-to-operate PC programs, permit the calculation and design of new ball mills, and a critical evaluation and optimising of mills in operation.

Jan 1, 1993

By Armstrong RW, Middlin B

The development, design, construction and operation of the new Solvent Extraction/BCA process plant at Copper Refineries Pty. Ltd., Townsville is described.The process offers substantial savings in electrical power costs, improvements in plant hygiene, and a lowering of materials handling costs compared with conventional electrowinning technology.The solvent extraction process extracts arsenic from copper Tank House electrolyte using a tributyl phosphate (TBP) - kerosene solvent. The plant incorporates fourextraction stages, two scrub stages, and three stripping stages to produce an arsenic-bearing low-acid strip liquor. This strip liquor is mixed with copper sulphate, and neutralized with ammonia to form a copper (II) arsenic (V) crystalline product, bicupric arsenate (BCA). This product is then used in the manufacture of chromated copper arsenate timber preservatives (Royston 1982).

Jan 1, 1985

By Moore A. J

Control of blast vibration requires that its nature and causes be understood, and that effective control procedures be implemented to ensure compliance with limits related to the probability of damage to buildings/structures and human discomfort. This paper covers measurement equipment, assessment and prediction techniques, blast vibration control procedures and applicable statutory limits. It reviews current practice, and provides information on recent developments in blast vibration measurement equipment and control techniques, using examples based on Hunter Valley mining practice.

Jan 1, 1995

The undeniable fact of life in the next 25 years will be the increasing difficulty of the physical conditions of Australian orebodies facing future miners. We are all familiar with names such as the 3000 orebody at Mt Isa, Hilton, Century, Macarthur River, Cannington, and Ernest Henry. These projects represent a significant. proportion of the planned underground mine development in Australia. Moreover, many of these new orebodies are an order of magnitude more difficult to mine and process than their predecessors. Extraction will be from deeper and potentially more hazardous working environments. Occupational health and safety considerations will place unprecedented demands upon mine operators and technology providers of the future.

Jan 1, 1994

By Appleyard B

The objective of this paper is to provide a brief to The AusIMM initiative which originated in 1996 and has developed from a concept proposed by Ric West, a Sydney consultant. The notes which follow are drawn primarily from a paper included in the Ironmaking Resources and Reserves Estimation Seminar volume presented by Vivienne Snowden, a member of the Towards 2000 Steering Committee and of the JORC committee.

Jan 1, 1997

The paper presents the results of laboratory blasting and grinding experiments on a low-grade iron ore, investigating how blasting will influence the subsequent crushing and grinding operations. Increased blasting energy will lead to a reducti

Jan 1, 1998

The safety of mine winder systems with regard to overwind, underwind, rope factors of safety, winder brakes and the like is discussed. Many misunderstandings and poten- tially unsafe practices are discussed as well as variations between requirements of various Mines Departments. Various methods to improve safety are suggested and the formation of an industry committee to review present practice and foster development of improved safety and economy is also suggested.

Jan 1, 1984

Mr. Bradford said: - On assuming this chair, which has been oc- cupied by so many gentlemen of conspicuous ability, my first words must be an expression of the gratitude I feel for the honour you have done me in electing me to be your President for this year. When considering the subject matter of this address to you to- night, quite frankly may it be stated that for a long time I was on the horns of a very great dilemma, for while I could discourse on the modern political trend in relation to our industries at great length, it appeared to me that this was not the place for such a discussion.

Jan 1, 1987

By Shiels O. J

The paper reviews developments in general galvanising in Australia, including a brief history of the industry and its technology. The changes in galvanising process technology are covered, as well as developments in galvanising bath design, materials handling and pre-treatment. Developments in zinc management through the use of aluminium and nickel alloys are discussed. The paper addresses the cost components of general galvanising and relates this to the competitive position of general galvanising against other coatings used for protecting steel. The environmental aspects of the general galvanising industry in Australia are outlined with respect to the utilisation of process chemicals, problems associated with their disposal and developments in filtering and regeneration of process solutions. The current status of the industry is assessed in terms of zinc usage and usage trends. Likely changes in technology which may impact on the general galvanising industry in the future are reviewed.

Jan 1, 1993

Erratic, though spatially localised occurrences of gold particles are a common feature of high-nugget gold systems. In many cases, gold is present as isolated or clustered, often coarse particles. The nugget effect is a part consequence of small-scale geologically controlled enrichment, and the inclusion or exclusion of gold particles from samples. Economic zones are generally contained within discrete structurally-controlled ore shoots which are surrounded by, and may include barren to low-grade background material. Problems are often encountered where small sample types (eg drill core and channel samples) of a few kilograms mass understate in situ grade by up to a few orders of magnitude, due to their general inability to represent the true gold particle distribution. This leads to uncertainty in mineral resource estimates. This contribution presents case studies where geologically-based parameters have been collected from drill core and underground faces to support grade determination. These parameters - or proxies - are based on mineralogical and/or geochemical (eg specific elemental ratios, fluid inclusion compositions and elemental correlations) criteria. Such criteria can be correlated with different grade domains to provide an indication of true grade within a geologically-controlled context. Proxies have recently been used to support resource estimates reported in accordance with the JORC Code.

Mar 1, 2010

By Fitzpatrick JM

The feed preparation section of the Whyalla iron ore pellet plant includes a screening and crushing plant followed by dry grinding mills. Improvements in the efficiency of the vibrating screen and cone crusher have enabled screening plant throughput to be increased and product size to be decreased. This, in turn, has enabled improvements in the grinding mills' operation.

Jan 1, 1978

The use of systematic review methods, derived from System Safety approaches used in the North American nuclear power industry, have become an accepted approach for seeking "approval" for new coal mining equipment and operational changes in NSW. Based on risk analysis, they provide a valuable and needed framework for the reduction of losses related to people, equipment and production.

Jan 1, 1991

This paper describes a plant built at The Broken Hill Associated Smelters, Port Pirie to sample lead sinter automatically. As the plant is still in the commissioning stage results on the precision and accuracy of the sampling are not yet available, but some of the difficulties experienced during commissioning are discussed.

Jan 1, 1976