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By Coulter K. W

The commercial evaluation of coking coal from bore core data will begin with a technical evaluation of the coal properties affecting coke quality. Methods currently used for prediction of coke.properties from coal analysis are illustrated but in each case accuracy of measurement and prediction should be clearly understood. It is suggested that coal be initially valued from coking properties (base value) and adjusted for chemical properties (merit value). Final evaluation of coal can only take place as coke in the blast furnace where the coke is assessed under high temperature operating conditions. The commercial value of a particular coking coal will depend on many additional factors other than the technical properties.

Jan 1, 1977

The Taupo Volcanic Zone (TVZ) is the largest active volcanic belt in New Zealand. It is

Jan 1, 1987

As Coal Mining Areas develop, problems relating to strata control increase. The "easy" coal has been extracted and the future development lies in the direction of greater depths of cover and more difficult strata conditions. To provide solutions to the problems encountered the techniques of constructing and testing physical models have been developed and refined. With a sound knowledge of model theory allied to practical experience, mining research engineers use physical cemented material models to examine, assess and solve mining problems relateu to strata behaviour and environment. For a model to provide the answer to a particular mining problem it is essential that as much information as possible be obtained from the mine or area of a mine which the model is to represent. Details relating to the strata, geological malformations, and the stress environment must be collected and collated to ensure reliable results.

Jan 1, 1976

The Broken Hill (BH) Block contains a wide variety of mineralization, with comrodities including Pb, Ag, Zn, W, Cu, Co and Sn. Much of the mineralization is stratigraphically controlled. Fe, Cu and Co-rich mineralization is dcminant in the Thackaringa Group; Pb, Ag, Zn and W is dcminant in the BH Group and Sn mineralization is present above the BH Group. Some mineralization occurs as concordant syngenetic deposits, but other types have been partly or completely remobilized by metamorphism, magmatic activity or hydrothermal fluids. Almost all of the non-syngenetic mineralization, including stratabound, vein and intrusive-related types, has formed from the "recycling" (remobilization and redeposition) of metals originally deposited with the sediments and volcanics of the Willyama Supergroup.

Jan 1, 1983

By Alford R. A

The causes of the loss of heavy mineral from mineral sands wet concentrators were identified through detailed surveys of two such concentrators. It was found that tray and spiral sluices preferentially lost elongated panicles, but panicle size had little effect on loss. Recovery was shown to increase with panicle density. The major influences on the recovery efficiency of individual concentrating devices (stans) were feed rate and feed grade, recovery increasing with decreased feed rate and with increased grade. Uneven distribution of total solids and heavy mineral to individual stans contributed to losses through the corresponding effects in feed tonnage and grade. Computer simulation demonstrated that significant recovery improvements could be obtained by appropriate adjustment of splitters to optimise the characteristics of internal plant flows.

Jan 1, 1991

A general approach to the analysis of processing technology is presented using the concepts of Process Aims, Process Characteris- tics and Process Costs. From an examination of the processes used in extractive metallurgy a hierarchy of process aims is identified, these aims are separation, compound formation,, metal production and metal purification. The application of this methodology to process flowsheet development is described.

Jan 1, 1984

By A Kyllo a, D R. Swinbourne

Electric arc furnace (EAF) dusts contain significant quantities of zinc, found almost entirely as either zinc oxide or zinc ferrite. The dust has been classified as a hazardous waste due to the relative high lead, cadmium and hexavalent chromium contents. It is important that environmentally acceptable processes be developed to treat this waste. One possible process involves reacting the zinc compounds in the dust with metallic iron, thus avoiding zinc vapour reoxidation by CO2 as occurs in carbon reduction processes. It consists of two stages where the first is the reduction of iron oxides to iron and the second the reduction of zinc oxide to zinc vapour by the iron. In this work the effects of operating variables such as temperature, CO/CO2 ratio and pressure on the recovery of zinc from an industrial EAF dust obtained from the Smorgon Steel Mill were investigated. Zinc recoveries in the second stage were found to approach 100 per cent at 1000oC after about four hours in nitrogen but within 40 minutes if a low vacuum was used.

Jan 1, 2000

Over the last 100 years in the Polish mining industry considerable work has been done to assess optimum slurry, develop flexible delivery systems and adjust the fill technology to a wide variety of mining and geological conditions. Sand or industrial mineral waste materials for the backfilling of underground voids are used to control ground movement and surface deformation. This paper discusses various criteria to be considered in the preparation of a fill, including slurry properties, mine infrastructure, mining geometry, placement methods and the purpose of the backfill. This paper presents laboratory and in situ test data on the influence of materials parameters on the slurry flow in a pipeline system, stiffness, permeability, binding time and strength of a backfill, on the distribution of mixture in underground voids or the penetration between roof fall materials.

Jan 1, 1998

By P J. Harper

Maximising shareholder value is a widely stated strategic goal of many mining companies. Mining projects can be capital intensive and achieving good returns is essential to encourage future investment in the industry. Despite the widely accepted importance of shareholder value, the minerals industry is often accused of providing relatively poor returns when compared to other industries. There are many recent and well publicised examples of minerals companies that have failed to deliver value to their shareholders. There are numerous business improvement initiatives employed within the mining industry to assist mine operators improve performance. Some are more effective at creating value than others. Benchmarking is one technique that is commonly used to identify performance gaps and target and prioritise opportunities for improvement. However to be effective, Benchmarking must be used appropriately and result in actions that lead to measurable operational improvement. When conducting a Benchmarking project it is important to remember that the aim should be to improve value. For this to be achieved, the strategic goals must be incorporated into the process. This paper details a structured and comprehensive approach to conducting a successful Benchmarking project. Focusing on Benchmarking as a technique for measuring and improving operational performance in underground mines, the underlying drivers of best practice in underground mining are identified.

Jan 1, 2005

The Perth Mint receives gold and silver from various sources for evaluation and refining. The metals are received in many forms and vary widely in assay. Refining is carried out using the Miller Process and the and the resulting market quality bullion is sold in a range of weights and alloys to suit the international bullion market and public demand. INTRODUCTION The Perth Mint was established in the late nineties as a branch of the Royal Mint, London, to refine the gold from the newly established gold- fields in Western Australia. The branch was opened for business in June, 1899. After refining, the bulk of the gold was used in the manufacture of sovereigns and half-sovereigns. Nowadays, although most of the gold received comes from the W.A. goldfields, some gold is deposited by producers in other states and in Papua-New Guinea, as well as scrap and trade wastes from manufacturing jewellers and old jewellery from the general public. Silver is deposited in the form of old silverware, recoveries from-photographic processes etc. Gold or silver may be lodged at the Mint in person, through a bank or other agency or by registered post. Telegraphic advice is usually given when gold is sent by the latter, so that insurance may be effected.

Jan 1, 1982

By Sauer P

The features of Banana screens have been known for some considerable time and recently considerable interest has been generated in the performance of these units. This paper reviews screening principles on Banana and conventional units and demonstrates the capacity and effic- iency of these units. Furthermore, the behaviour of modern Banana screens and modem screens in general, are examined with respect to life, vibration isolation, noise emission and maintenance requirements.

Jan 1, 1978

In 1972, with the West Lyell Open Pit winding down, mining operations transferred underground. All development tunnelling until the end of the decade was carried out by a fleet of ten pneumatic Jumbos.A decision was made in 1980 to purchase an electric-hydraulic Jumbo and a second was purchased in 1982. Their introduction changed the face of development at Mount Lyell. Significant new demands were placed on main-tenance sections, particularly on electrical reticulation.Subsequently, two further electric-hydraulic Jumbos were purchased from Agnew Mining in 1984, and successfully overhauled and commissioned. As well, two electric-nydraulic production drilling rigs have been purchased. Only one of the original pneumatic Jumbos remains in service.

Jan 1, 1985

Patterns of successful metallic mineral discoveries in Australia are analysed for the last three decades. A trend towards more discoveries of poorly expressed and blind ore- bodies is evident and can be expected to continue. Discoveries using traditional and conceptual geological techniques have proportionally declined but are expected to continue at a significant level for a decade or so. Improvements in the quality and numbers of geological exploration models and in the quality of available basic geoscience data have aided successful discovery in recent years. Although some orebodies for the Year 2001 have already been found maintenance of a strong mineral inventory demands that more and better geological models are applied. Empirical models need to be improved by critical multi- disciplinary integrated studies of mineral occurrence at all scales. New models can and will be developed by various means. If application of these models is made with all the innovation, initiative and unorthodoxy that can be mustered then new discoveries will result. Greater attention to the surface expression of orebodies will also lead to new discoveries. Review and follow-up of old data in the light of new concepts will provide yet another discovery route.

Jan 1, 1981

Congratulations on your considerable enterprise in securing the opportunity to have this international conference here in Brisbane - and congratulations on your success in attracting such a distinguished audience from so many nations, with such a broad selection of papers. It is a notable achievement that in the year in which Australia is celebrating two hundred years since settlers first came fran Britain, The Australasian Institute of Mining and Metallurgy is responsible for some ten major conferences, of which at least four are specifically international, or have a very strong international involvement.

Jan 1, 1988

The current insurance market has been brought about by a number of pressures, including: collapsing investment returns; growing losses, both normal and catastrophic; and reserve strengthening. This is impacting most classes of insurance coverage, with the traditional characteristics of higher pricing and greater levels of retention, however it is now translating into a lack of capacity and reduced coverage. This presentation will explain how the market has arrived at this situation and will challenge whether this is the traditional insurance cycle or a structural correction. It will also address the anticipated time of correction.

Jan 1, 2003

It is with great pleasure that I accepted the invitation to make a closing address to this Congress particularly as it is here in Brisbane. The main duty of the International Mine Ventilation Congress Committee and in particular the chairman is to ensure that these conferences are held every four to five years in suitable locations. My main role over the last four years has been to promote holding this Congress in Australia and it was a great relief when the Queensland team and the Australasian Institute of Mining and Metallurgy accepted the challenge in November 1986.

Jan 1, 1988

The procedures for an audit and review process upon which continuous improvement programs may be based are described. The case for regular audits of mining operations to establish performance trends is advanced. Analysis of performance data using the parameters of the capacity equation used in conjunction with learning curves is described. The extrapolation of learning curves in performance target setting, operating and capital cost budgeting is advocated.

Jan 1, 1992

By Peck WH

For many years it was realised that the methods used for unloading concentrates at Port Pirie were inefficient and labour intensive, therefore, when a decision was reached to standardise the east-west rail link from Sydney to Perth, the opportunity was taken to consider entirely new schemes for the handling of concentrates at Broken Hill and Port Pirie. After considerable testing and investigation, it was decided to install a completely new concentrates handling plant incorporating a tippler at Port Pirieòto replace the previous long established methods of unloading and dis- tributing concentrates to the operating plant.and the shipping berths. To achieve this, wagons of concentrates from the various mines are marshalled in a set order at Broken Hill and conveyed to Port Pirie in 56-wagon trains. On arrival at Port Pirie, the wagons are checked and moved to a position where they come under the control of the automatic wagon marshalling equipment.

Jan 1, 1975

This paper discusses how the i-kon TM Digital Energy Control System may be deployed by miners of massive underground orebodies to deliver significant advantage in terms of safety, cost and environmental compliance. Digital Energy Control offers an exciting opportunity for mine operators to review their blasting and mining practice to gain the most advantage from this new technology.

Jan 1, 2000

By R Ashworth, S J. Hall

During trials which began in May 2005, traditional steel dump bodies for transporting iron ore on 220-tonne haul trucks at a Labrador iron ore mine were compared to a novel rubber suspended dump body. Loads were measured and compared over some 93 700 loads, representing more than 20 Mt transported. Maintenance costs and downtime were also measured over the course of the trial, which lasted nearly one year. This paper outlines the parameters and results of the trials. Parameters measured included payload and production improvements, carry-back reduction, downtime due to body maintenance, and wear on the floor of the suspended dump body. These parameters were then compared to those for conventional steel dump bodies in use at the mine, and conclusions were drawn. The resulting comparisons were significantly positive in favour of the new suspended dump bodies, confirming that each truck could haul an additional 41 000 tonnes per year, that downtime hours could be considerably reduced, and that body availability and service life can be extended through use of the suspended dump body. There was also a high level of operator acceptance of the suspended dump bodies due to less loading shock and a smoother ride.

Jan 1, 2007