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Over the last few years several important developments have taken place in the Electro- lyte Purification Plant at Copper Refineries Pty. Ltd. A fully automated system for the continuous removal of arsenic has been develop- ed. A submerged combustion process for the removal of nickel has been developed to a stage where patent coverage has been obtained in most of the copper producing countries. A plant has recently been commissioned for the production of Tetra Cupric Arsenate, which it is hoped will find a ready market in the timber preservation industry.

Jan 1, 1974

By Parker RL

A 250 tons per day ammonia-ammonium carbonate leaching plant is now being operated by Samin Limited, to extract copper from the oxidised ores at the Burra mine. This forms the first stage of a plant, which will eventually have a capacity in excess of 1,000 tons per day. The article reviews the history of the mines at Burra and the metallurgical studies which have been undertaken since the old mines closed in 1917, in an endeavour to recover the copper from the low-grade deposits left by the original miners. The reasons why an ammonia leaching process was selected instead of the conventional flotation or acid leaching methods are discussed. The paper concludes with a detailed description of the plant and the basis on which it was designed.

Jan 1, 1971

External pressures are being exerted on busi- ness, and especially the mining and energy in- dustries, as never before. These pressures are burdensome, they emerge in unique forms, and they constitute an entirely new operating environ- ment for business. They pose one of the signi- ficant challenges to senior management today. To cope with these pressures-which we have termed the new public realities-we must deal more effectively with the media, the public, and government. However, before examining methods for improvement, it is essential to understand the nature of these new public realities and par- ticularly their determinants-the underlying eco- nomic, sociological, political, and international events and trends which have shaped them. Previously the productive element of society had only to concern itself with what might be termed `conventional realities' : the costs of labour, equipment, and land, as well as marketing and distribution factors.

Jan 1, 1978

By M Freeman

Significant improvements in the metallurgical performance at Pasminco Rosebery Mine have occurred over the last two years. Lead and silver recoveries have increased by more than ten per cent, lead concentrate grades are four per cent higher, zinc recoveries are up 1.5 per cent, and zinc concentrate grades have increased by two per cent. These impressive results have not occurred through the application of some new wonder reagent, but through the application of some fundamental metallurgical principals. The basic premise applied during this study was that to make an effective separation you must first achieve liberation. Therefore, the laboratory and plant studies examined the liberation characteristics within the lead circuit, and the impact of regrinding. The work demonstrated clearly that galena/sphalerite liberation was poor, and significantly impaired plant performance. Further, it was suggested that the application of lead regrinding of the lead scavenger concentrate and the lead first cleaner tailing would not only benefit lead metallurgy, but also improve sphalerite flotation. A similar approach was then applied to the zinc circuit. From these studies, solutions applying simple circuit changes utilising existing equipment were proposed and implemented. Further to the improvements in galena/sphalerite liberation, significant improvements in concentrate quality were achieved by reducing variation within the process. The implementation of changes in work practices negotiated in the Enterprise Agreement, employee contributions and specialist training also made a significant contribution to the unprecedented improvement in the lead and zinc flotation circuit performance. The results of these plant changes are discussed, along with the suggested scope for further improvement.

Jan 1, 2000

By Ya Vladimirov D, Yu Khudin M, Kiebanov A. F

Problems of the creation of an automated cartographic system for environmental condition estimation and forecasting in mining region are discussed in this paper. The Geographic Information System (GIS) ARC/INFO is offered as the platform for such a system. A breadboard model of the system was tested on the example of Kemerovo province (Kuznetsk coal basin), the most ecologically impacted mining region of Russia. As a result parameters of territorial distribution of integrated adverse environmental impact of the industrial enterprises are reviewed. Administrative regions of Kemerovo province were rated according to a degree of environmental pollution. Further, specific weight of various industries in pollution of region is determined.

Jan 1, 1995

By Linkson PB

The presence of residual cyanide in mine tailings and fill sands may, under specific circumstances, lead to acute and/or chronic cyanide poisoning of the environment and individuals. In this paper, the nature of cyanide contained in mine tailings is discussed, along with the circumstances under which such cyanide would become a hazard. A number of methods for cyanide degradation are reviewed in the paper, with special emphasis being placed on biological degradation (due to its low costs and the non toxic nature of the degradation process itself). Recommendations are made as to the best methods of setting up a biological degradation system, for use in mining Situations.

Jan 1, 1987

Pulverised coal firing was pioneered in the cement industry prior to the turn of the century. Ash from the coal is absorbed into the mix in the kiln and replaces secondary materials. With high purity limestone coal with high ash content can be used. Fuel cost is a major part of the total manufacturing cost. Cement plants are thus quick to respond to fuel price changes and will use low grade fuels if there is a price advantage. Combustion conditions in a cement kiln differ markedly from a boiler. Flame length is determined by air/fuel mixing but because of fixed secondary air conditions this depends on primary air momentum. Volatile content has some effect on flame length but this can be offset by coal fineness. Much of the heat for cement production is for limestone calcination which is a low grade energy requirement. By allowing long residence time in separate direct fired vessels which then feed the high temperature kiln the energy of materials such as oil shale, tyres and lump lignite can be utilised.

Jan 1, 1987

By Nichol R

- PART A The Hoppers Crossing Pumping Station is one of the principal components of the Western Trunk Sewer Project which replaces the 90 year old Main Outfall Sewer and will convey 60% of Melbourne's sewage flow from Brooklyn to the Board's Farm at

Jan 1, 1987

By Weber D, Knox PR

The criteria developed for the Argyle Diamond Mine process plant control system are reviewed. The control system installed is described along with a discussion of the method of implementation adopted. The control system was extensively tested prior to instal- lation at site. This approach led to signi- ficant time savings during plant commissioning and facilitated rapid escalation of plant production. The control system has performed satisfactorily with a high level of operator acceptance and basically satisfies the criteria Developed.

Jan 1, 1986

By M Thomas, S Lambert

The Tugun Bypass Tunnel in Gold Coast, Australia was constructed using diaphragm walls with the top-down cut-and-cover method to allow simultaneous construction of an airport runway extension above the tunnel, whilst excavation of the tunnel continued underneath. The tunnel was built in an environment of high groundwater table and deep deposits of alluvial and estuarine soils with the toes of the walls founded in soil deposits. There was a potential risk for differential settlements to occur between the diaphragm wall panels, caused by the runway fill placed over the tunnel roof during excavation. Dewatering within the diaphragm walls was required to facilitate the construction of the tunnel. The tunnel was also built in an area where environmental considerations were of great importance. Three-dimensional numerical modelling was undertaken to predict the differential settlements of the tunnel with considerations of varying subsurface profile, staged excavation and dewatering, non- uniform surface loading and complex soil-structure interaction. Field instrumentation and monitoring was implemented to confirm numerical predictions.  

Jan 1, 2008

The Skybolt is a new bolt concept, point anchored with resin in large diameter holes of specific sizes 38 mm and 45 mm. The new design achieves the optimum annular spacing required for mixing the resin anchor components which is essential for optimum resin bonding of the bolt to the surrounding rock. This paper explains the load transfer mechanisms between bolt/resin/rock, unique to this bolt concept. It compares the pull-out test results to those of paddle and expansion shell type bolts, and highlights the versatility of Skybolt over existing, currently used, rock support systems and the benefits mine operators can achieve when using the Skybolt.

Jan 1, 1992

Mining companies around the world are seeking methods to coordinate operations between the mine and the concentrator to achieve an overall improvement in enterprise performance. In several instances very significant increases in productivity (more than 20 per cent) and profitability (more than $US 10M per annum) have resulted from such efforts. The key to realising these large benefits has for the most part arisen from improved communication between mining operations and plant operations personnel and the judicious use of new tools to evaluate alternatives for improvement and to minimise the risk of implementation. This paper presents a systematic approach to mine-to-mill optimisation . The importance of systemic thinking and systems optimisation methodologies is emphasised. New tools for evaluating operational performance are discussed. Recently reported benefits are summarised. Finally current research is discussed and projections for the future are given.

Jan 1, 2000

By Blair JR

The tunnel alignments investigated for the Gosford Regional Sewerage Scheme are located in the Terrigal Formation and are covered for most of their length by a thick blanket of soil and weathered rock. The following techniques were found to be most effective in geotechnical investigations for tunnelling in this area: air-photo interpretation, seismic surveys to pinpoint drilling targets, in-situ measurements of strength,deformation modulus and permeability in cored holes, and the construction of rock- mass models. Cross-hole seismic modulus measurements, surface resistivity soundings and electric well-logging techniques were found to have limited applicability due to adverse local conditions.

Jan 1, 1976

By Chenggang W, Junhua D

Fragmentation variation laws in loading and non-loading areas are obtained by cement block model blasting experiments under various stemming lengths. A reasonable ratio between loading length and stemming length is worked out according to minimum average fragment size. The present continuous loading structure, for its very long length to be stemmed, leads to insufficient fragmentation in the upper part of bench. So a new loading structure with bottom air cushion is put forward. The author analyzes blasting effects and processes of two loading structures' and proves that there exists a optimal length of air cushion.\

Jan 1, 1990

Deposits of chromite are in associated with ophiolite complexes in Papua New Guinea. No deposits which are currently exploitable have been recognised, but large resources that may be economic in the future are present at Ramu area and on the Morobe coast. These are contained either in laterites or in sediments derived from ultramafic members of the ophiolites. There are possibilities of establishing further resources either in similar settings or associated with ultramafic members of alkali intrusive Complexes.

Jan 1, 1987

The Amacan Copper Project was constructed in the Philippines by a Finnish-Filipino Consortium during the years 1979 - 1982. The project involved a turnkey contract for a mine and a concentrator to process 25 000 tonne per day of porphy- ritic copper ore at a grade of 0.45% Cu. The orebody is located on Mindanao, the southernmost island of the Philippines, in rugged, mountainous terrain approximately 1 000 m above sea level. The adopted design principle was based on an efficient, straightforward installation utilising a minimum number of items of equipment each with high unit capacities. The consortium faced many problems which resulted in lengthy delays in construction and finally led to the client taking over responsibility for the completion of the project. The concentrator was successfully commissioned in July 1982.

Jan 1, 1986

By Ahmed M, Leung L

A program of microseismic noise monitor ing for gas outbursts, in conjunction with other mining engineering measurements and observations, is being undertaken at Leichhardt colliery in Queensland. Headings are developed at present by shotfiring. The equipment being used in this study includes piezoelectric accelerometer assemblies to detect microseismic noise which is then transmitted to a surface base station by cable. Data are recorded on an analogue magnetic tape recorder and are also analysed on-line using a commercially-available acoustic emission pulse analyser. It is proposed to re-interpret recorded data using various modes of analysis and to interface a desktop computer to the existing system to permit continuous monitoring on the mine site. No outbursts have been recorded or analysed and only a limited number of develop- ment shots, and the resultant microseismic activity, have been recorded to date.

Jan 1, 1980

By Itoh K, Sakai K, Tsuji K

In Japan there exists a strong demand for mechanical excavation for tunnelling bacause the blasting method which produces much vibra- tions and noises is restricted in its applica- tion due to the fact that there can be many cases where tunnelling sites are located ad- jacent to residencial areas as a result of Japan's being a thickly inhabited country. Pressing demands for and deep interest in the mechanical excavation method have been shown by the circles concerned with reasons that it produces smooth cutting surface and causes less overcutting of profile as a result of the diffusion of NATM (New Austrian Tunnel- ling Method) in the recent years. This has caused a strong desire of the users to apply the conventional mechanical excavation method that has been used mainly for soft rock cutting also to the field of hard rock cutting. In order to meet such needs of the tunnel- ling industry, further research and development have been continued to have successfully real- ized the Boomtype Tunnelling Machine for Hard Rock.

Jan 1, 1987

By Gostylla W

The economic feasibility of controlled district cross-cut recirculation is examined in this paper with particular reference to the most important mine ventilation network parameters. An algorithm is developed to express the annual cost of recirculation which is then compared to the annual cost of conventional ventilation using the University of Queensland Experimental Mine as a case study. The concepts of resistance ratio and volumetric efficiency ratio are introduced and used to analyse the economic feasibility of controlled recirculation within a mine ventilation network.

Jan 1, 1988

By Millen M. J, Rainey S, Sowerby B. D

The control of size reduction in grinding machines and circuits may be enhanced by a continuous and accurate measurement of the particle size of solids in appropriate process streams. This paper presents a brief review of commercial particle s

Jan 1, 1997