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By M W. I Visser Æt Hooft, R C. Schimmel

Until recently the Corus IJmuiden pellet plant produced approximately 4.5 Mtpa of pellets. Corus IJmuiden is currently running a program to increase its pig iron production to 6.4 million tonnes HM per annum. The burden of the Corus IJmuiden blast furnaces consists of approximately 50 per cent high basicity sinter and 50 per cent acid pellets, both produced in-house. To accommodate the increased pig iron production, the capacity of the pellet plant needed to be increased to 5.0 Mtpa. The productivity was increased by modifications to the plant layout, which were implemented during the 2006 cold maintenance stop. In addition, the composition of the ore blends is optimised to gain productivity.

Jan 1, 2007

Computers are playing an increasing role in the management of technical data in mines. Companies are re-assessing the role of their data processing departments as users demand computer resources in non-accounting areas. Data of all kinds is now being seen as a, company resource, and the role of computing professionals is to help to manage the data flow, not merely to manage computers. The concept of distributed data bases puts the responsibility for data entry, editing and updating with the user. This challenges conservative views of centralized control of computing, suggesting, instead, centralized co-ordination. A survey of the possible applications of computers in technical areas points up the special requirements of handling raw, processed and consolidated technical data. Technical data bases have become flexible as mini- computer hardware and software have rapidly developed. Management has the ultimate responsibility for efficiently administering corporate data bases, and it must ensure suitable policies are developed for this purpose, with enough flexibility to cope with the impact of fast changing technology.

Jan 1, 1980

A wide variety of process streams are sampled for grade control in the mining industry. However, in many instances the overall precision of the resultant analyses is inadequate for the intended purpose, ie grade control and optimisation of resource utilisation. Consequently, special attention needs to be given to the sampling, sample preparation and analysis procedures in place to ensure that meaningful grade control decisions can be made based on the analyses generated. For example, it is virtually impossible to control a process to within, say, ¦0.2 per cent if the overall precision of the analyses is no better than 0.5 per cent. Hence, precision targets appropriate for the task need to be established and the overall precision achieved in practice monitored and controlled on an ongoing basis.

Jan 1, 2008

By Gadsden R. W

Physical and chemical requirements are defined for coke and ferrous materials used in modern high productivity blast furnaces operating in Australian conditions. Recent developments in the type of equipment required to be installed at the steelworks to ensure these requirements are described with illustrations from current plant practice provided.

Jan 1, 1976

By K H. Esbensen

The critical role of representative sampling is featured and illustrated by selected examples from the geosciences and beyond. As there already are many demonstrations of the potential (and potentially large) economic consequences of ignoring proper standards with respect to representativity, eg for mining and minerals processing companies, which æstand to lose millions of dollars by failing to optimise exploitation of their mineral resourcesÆ, such need no further iteration here.This keynote lecture, rather, takes a point of departure from the opposite perspective: what is to be gained by a scrupulous stand for representativity? Honesty, reputation, credibility, market advantage - is what!CITATION:Esbensen, K H, 2012. The critical role of representative sampling, in Proceedings Sampling 2012 , pp 9-12 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 21, 2012

By Ellicott C, Webb N

In November 1996 the NSW Minister for Mineral Resources, Hon Bob Martin MP, commissioned ACiL Economics and Policy Pty Ltd to conduct a wide ranging review of safety within the New South Wales mining industry.The review was a response to a disturbing number of fatalities which had occurred in the industry during the Minister's term of office together with a number of alarming near misses where serious failures in mining systems had occurred. Shortly after the review was commissioned, four mine workers died at Gretley Colliery near Newcastle. An inquiry is currently being conducted into the incident.

Jan 1, 1998

By M Warren

The professional geologist or engineer on a mining operation has a particular view of their operation. This is based on the factors of the operation that have a direct impact on the daily work program of the professional, such as production rates and grades. The view that would be taken by a financier who is called upon to support the project may be somewhat different. The value of the operation to the financier is in its ability to generate surplus cash for its owners and thus repay the debts to the financiers, with as low risks profile as possible. A number of tools are used to test the sensitivity of the project to variations in the key cost/revenue drivers. The Financier may call on a team of technical specialists to assist with the assessment of the cash flow and risk profile and to monitor the development of the project. The ability to offset this risk, as all projects have some degree of risk, may be a key factor in determining the level of financial support to be offered.

Jan 1, 2002

By Gordon DM

SUMMARY Tyres account for 25-30% of the operating costs of large capacity haul units as used in open-cut mines. Tyre operating costs can be substanti- ally reduced and often contained in real terms by applying knowledge that is now available. This paper describes certain specific advances in tyre management, namely batching, bias adjustment, cumulative plotting and the so-called "pressure-temperature" system of tyre pressure control, originated on the Mt. Newman Mining Company's Newman minesite, and discusses the contribution that each has made to improving tyre management and reducing costs. INTRODUCTION Tyres are a significant cost in mining. Tyre costs make up between 25% and 30% of the operating costs of large (i.e. 100 tonne and larger capacity) open-cut mine haultrucks. On a large mine this tyre cost may amount to several millions of dollars each year. It is a fact that through careful

Jan 1, 1982

The port of Townsville is situated on the main north/south rail system of the Queens- land Government Railways and is the eastern terminus of the east/west rail link from Towns- ville to Mount Isa. With a stable beef and wool producing area along the east/west rail route, the expanding mineral industry development at its western end and the continuing growth of the Townsville region the administrators of the port are continually'keeping abreast and ahead of port development to ensure an effective and economic growth of port facilities to meet the needs of the area served by Townsville.

Jan 1, 1974

The hazard posed by underground mine fires is illustrated in the first part of this paper by means of a review of experiences in four mining countries over the last three decades. This brief review indicates that while much progress has been made generally in preventing fires and providing means of protection to miners, the possibility of disasters occurring must continue to be regarded as very real. Based upon recent investigations by the South African mining industry, an integrated strategy for providing protection to personnel in the event of a fire is outlined in the second part of the paper. The main, complementary, elements in this strategy are the prevention of ignitions, the limitation of fires, provision of protection systems and equipment, training for emergencies, and effective implementation of safety measures. Some comments are made on important aspects of these elements and on possible further developments.

Jan 1, 1988

By Cook B, Cunningham J

At Mount Isa Mines, a system has been developed for general monitoring of underground mobile equipment. It can provide unit condition monitoring data such as oil pressures and motor temperatures as well as production type information such as unit location and load. The system does not rely on an expensive data communications infrastructure, using instead inexpensive radio base stations which automatically transfer data from mobile units to a surface database server on the company-wide computer network. This paper includes a general overview of the system and a discussion of the practical benefits it is expected to generate.

Jan 1, 1995

Ion exchange resins are an attractive alternative to activated carbon in both column and resin-in-pulp processes for the recovery of gold from cyanide solution. Resins are widely used for this purpose in the Soviet Union apparently in preference to activated carbons.A wide range of resins are available and the high level of resin technology is demon-strated in the resin processes used to recover uranium.The anionic gold complex, Au(CN) 2 , is selectively adsorbed onto weak and strong base resins. However other anionic cyanide complexes, cyanide ions and other anions from the process water are also adsorbed onto resin sites. Resin selectively for gold is not as high as it is for activated carbons. As a result similar gold loading capacities are obtained for resins and carbons when used in plant liquors.

Jan 1, 1984

By Howell IJ, Kirsopp R

In June/July 1981 Mount Isa Mines Limited was confronted with a crisis situation in the crushing operation of the Lead/Zinc and Copper Concentrators. Three crusher mainframes developed serious cracks in the upper rim area. The type of cracking indicated that major failure of these mainframes could be imminent. Operational crushers could not be sensibly inspected and it was therefore assumed that more than three mainframes were seriously cracked. The crisis was averted as described in the following text.

Jan 1, 1978

The paper examines the possibility of applying the monolithic packing technique developed in the UK to the division of wide development drivages in Australia, so enabling double entries for longwall retreat panels to be created from shortwall units. The monolithic pack of the UK therefore becomes a monolithic partition in this proposed Australian application. A method developed for the analysis of the load development in packs installed behind longwall advancing faces is adapted and used to predict the support performance of the monolithic partition. Conclusions are made regarding partition construction and possible rates of advance.

Jan 1, 1986

This paper critically reviews the role of institutional research contractors (eg universities and the CSIRO) in the delivery of effective research, development and demonstration outcomes in mineral and coal processing to the Australian mineral industry. The criteria by which such R&D is justified, and the problems of quantifying the benefits of such research, are considered. Third-party funding mechanisms such as NERDDP and AMIRA are reviewed in the context of the difficulty of setting national research priorities. Some case studies are presented which illustrate both the problems and the advantages of institutional research for industry. The transfer of research outcomes to industry is identified as a significant problem which limits the effectiveness of all institutional research. Other topics reviewed include research management, the relationship between industrial companies and their research contractors, and the real costs of research. The paper offers suggestions for the ingredients needed for a successful industry-institution relationship, based on the Australian experience. It is concluded that the Australian model for this relationship is a very effective one, although there is still room for improvement.

Jan 1, 1992

By Walker V

The 'MAGNADET' to provide a safe enhanced protection extraneous currents, electricity and radiodetonator was designed electric detonator with against the effects of current leakage, static frequency energy.It has found a particular niche in shaft sinking operations and Mount Isa Mines initiated trials of the system in 1983 as part of the design work for the 3000/3500 orebody access shaft.Initial surface blasts indicated a number of significant advantages which were confirmed during the bench and concrete phase of the M37 shaft sink. The application of 'MAGNADETS' was later extended to the horadiam phase of the project.Details of the exploder capacity calculations for the various M37 round designs are included with the paper.

Jan 1, 1985

A very sensitive high-speed two-colour pyrometer was built to measure the temperature of single particles of sulphide mineral, typi- cally 50 pm in diameter, as they burnt while entrained in a hot gas stream. The pyrometer has been used to study the burning of pyrite and chalcopyrite particles and has thrown light on cenosphere formation. Measured maxi- mum temperatures have been compared with values predicted by diffusion-based models. The pyrometer has also been used to study the burning of small captive pellets (2-9 mmm dia- meter) of lead-zinc concentrate.

Jan 1, 1984

Diesel-engine exhaust emissions represent a concern to the mining industry due to the poten- tially harmful health effects of the pollutants, as well as high costs associated with providing proper ventilation to assure a healthful working environment. The control of exhaust emissions is complex since the operating mode and condi- tion of the engine, the mine environment, and the operator's skills all influence the concen- tration and composition of the emissions. It is not practical to measure each exhaust pollutant in underground mines; therefore, a monitoring methodology is required to measure the pollut- ants and assess the air quality.

Jan 1, 1988

By O Ostrovski

Direct iron smelting reduction has been examined using a modified 50 kg induction furnace. The furnace was equipped with continuous raw material feeding, a top oxygen lance, argon bottom bubbling, and sensors for measurement of gas and bath temperatures, gas composition and other parameters. In the base case, iron ore was charged at the rate of 1.5 kg/h, coke flowrate was adjusted to maintain a char fraction in the slag at 30 wt per cent, the oxygen flowrate was 100 Nl/min and the post-combustion ratio (PCR) was 60 per cent. The PCR was varied from 45 to 75 per cent by changing the lance height relative to the bath surface. Smelting reduction of Whaleback iron ore was investigated at different post-combustion ratios and iron ore feedrates using coke and coals with different volatile matter. The rate of iron oxide reduction increased with increasing iron oxide concentration in the slag, with a slight deviation from a linear function. The post-combustion ratio affected iron ore reduction and partitioning of elements between phases in the smelting reduction furnace. The high volatile coal investigated was found to be unsuitable for iron smelting reduction in the laboratory furnace.

Jan 1, 2000

By Jensen B

The approach of using the Coward Triangle for the analysis of flammable mine gas mixtures has been examined for its application, to the flammability of coal dust/gas/air mixtures. Explosible lean limit and rich limit concentration data for dust/methane/air mixtures are examined and illustrated using co-ordinate geometry. It is concluded that a three-dimensional envelope representing hybrid explosible mixtures can be drawn. The dimensions of this explosive zone will vary with the characteristics of the coal dust and the gaseous composition of the mine atmosphere. Further research is needed to establish these dimensions for important mined seams.

Jan 1, 1994