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By S M. C Verryn

The amount of raw material used in the production of cement can be reduced by partially supplementing it by pozzolanic waste material without changing its properties negatively. This paper discusses results of an investigation using slag from the Pt industry, from the production of steel using Midrex processes as well as fly ashes from different coal power plants in South Africa. These are blended in a 20 per cent slag or fly ash to 80 per cent cement ratio. The properties of the mixtures depend on the phase composition, chemistry, grain size and the sources of the materials. The results are promising, but show variable behaviour depending on slag and cement composition. Compressive strength tests as well have heat flow curves showing the hydration behaviour, indicating that 20 per cent addition of slag or fly ash to ordinary Portland cement is viable. There is a large potential to use slag in cement mixtures and this study can be used to develop cements that will positively influence CO2 emissions and help to reduce large slag and fly ash stockpiles.

Jan 1, 2008

Studies of the morphology of seamounts within the Hawaiian, Line Islands, Gilbert and Phoenix Seamount groups indicate that the morphology and size distribution of seamounts vary significantly from one seamount group to another. The Line Islands group appears to be the most complicated of all the groups studied thus far. This group is complicated by reactivation of volcanism, which has superimposed volcanics on sedimentary rocks. These seamounts display abundant volcanic features on their summits. Seamounts within the Hawaiian seamount chain display a marked absence of volcanic features due to the . presence of thick carbonate caps. Reef platforms and sealevel benches are very common on these seamounts but are absent from seamounts in most other seamount chains in the central Pacific. Slope angles vary regionally between seamount groups. The minimum slopes are found on Necker Ridge in the central Pacific basin. The maximum slopes are found on ridge-crest seamounts. Roughness increases proportionally with mean slope angle.

Jan 1, 1987

Progress on this project will be verbally reported and a description given of the main features. A detailed feasibility study was completed in December 1986, and the Joint Venture has issued an Environmental Impact Statement. This was open for public comment until 16 February. Issues presently being considered include economic justification traffic, air quality, noise, marine fauna and flora, visual impact, heritage and construction impact. Detail design and construction is likely to commence in mid 1987, following determination of the above matters.

Jan 1, 1987

By Jena P. K

Smaller deposits of high grade chalcopyrite or the concentrates of low grade and complex copper bearing ores, can be subjected to extraction processes other than smelting and converting. Low temperature chlorination and segregation processes are among those mentioned in the literature. In the present work, extraction of copper from a Brazilian chalcopyrite concentrate by slurry chlorination with chlorine gas at room temperature, dry chlorination by chlorine gas in the temperature range of 350 to 450¦C and segregation roasting of the calcined concentrate in the temperature range of 650 to 800¦C have been carried out. The effect of several experimental variables on the extraction of copper has been discussed in all these cases. Under optimum experimental conditions, 100 per cent Cu extraction was possible by either slurry or dry chlorination processes and around 86 per cent Cu by segregation roasting. For all the three cases, possible methods have been suggested to trial the studies on a pilot scale to assess their technoeconomic viability.

Jan 1, 1992

The purpose, basic data requirements and various analysis/modelling tools employed for geomechanical evaluation of mine-site conditions are overviewed. The impact and application of computer technology are dis- cussed. Broad guidelines and criteria are presented for establishment of a practical geomechanics data-base system to yield infor- mation suitable for mine design purposes. Future needs of the Australian mining in- dustry are examined.

Jan 1, 1983

The role played by lawyers in business has, in the course of the last 15 to 20 years, changed perceptively. This development has coincided with, and indeed has been a reflection of, the changing nature of Australian business, especially as the mining industry established its predominance in the Australian economy. The nature and extent of governmental regulation of business, too, has changed markedly. As a consequence, there has been a qualitative'change in the nature of commercial law practice. For the needs of business to be met, lawyers have had to develop specialist skills in new areas. Furthermore, there has been the emergence of the "in-house" lawyer, who increasingly plays a primary rather than a subordinate role in corporate law practice. There is no evidence to suggest that this trend, which is by now so well established, will prove to be ephemeral. Instead, with all indications pointing towards even greater governmental regulation of business activities, the intimate role of the lawyer in business seems entrenched.

Jan 1, 1980

By Van Rensburg C S J

The options that are open to engineers for cooling mines are limited and are primarily dependent upon the thermophysical properties of coolants. These properties are carefully analysed in the context of cooling mines and a comparison is drawn among Ammonia (R717), Monochlorodifluoromethane' (R22), Dichlorodifluoromethane (R12) and Water (R718). From this comparison the extent of Ammonia's superiority as refrigerant is Evident.

Jan 1, 1988

By A Quigley

The Northside Storage Tunnel Project in Sydney includes over 20 km of TBM driven tunnels, over 3 km of declines and major caverns and pump rooms. The paper describes methods used for design on the project. Emphasis is given to the refinement of the use of empirical rock mass classifications, and to the use of discontinuum numerical methods.The use of empirical rock mass classifications in Sydney sandstone has usually led to conservative design because the systems are based on a random orientation of joints in the rockmass. Because the joint sets are usually oriented in a way that is beneficial for tunnelling, limits must be placed on the parameters used in the classifications system. The paper discusses these limits and the derivation of the parameters.The use of numerical methods in Sydney sandstone is discussed. Continuum methods have their uses, but discontinuum methods are preferred. The use of UDEC has been validated against a previous project, the New Southern Railway. Recommendations are given for UDEC models.

Jan 1, 1999

The first step in the mining and processing of nearly any mineral ore is comminution. Since the oil embargo of 1979, the mining companies have been striving to reduce energy consumption and costs. The first serious step was the introduction of in-pit crushing in the early 1980s. With in-pit crushing accepted as a standard design mode, the energy saving emphasis turned to comminution practices. A great deal of attention has been focused on blasting and grinding. The one step that has not been addressed is the primary crusher. This paper will address the opportunities for comminution improvement through optimisation of the primary crusher.

Jan 1, 2004

By Reifenstein A

ACIRL's petrographers apply microscopic techniques to coal exploration, production, preparation and processing problems and research investigations as well as provide a commercial service for quality control of export coal shipments. This paper describes a number of case studies of applications of petrography to coal industry problems and coal research, including

Jan 1, 1989

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

By S Ramsay, D Povey

This paper presents recent case study data collected by field portable x-ray fluorescence spectrum analysers (FPXRF) as part of grade control activities at three separate (nickel, copper and copper/gold) mining operations. FPXRF has been under utilised for grade control in recent years, largely because the success of early versions of FPXRF was limited to a few metals (eg tin). Efforts to utilise these early versions for other metals was largely unsuccessful and created a perception that FPXRF could not be utilised more broadly within the mining sector and specifically the area of grade control. The structural setting of the analytical function within mining operations has also contributed to the under utilisation of more recent FPXRF instrumentation. The concept of FPXRF as a grade control tool straddles the boundaries of the geology and laboratory departments. As such, this option is often not considered as part of an assessment of grade control procedures for new and existing mining operations. This paper assesses data collected by Australian and New Caledonian miners using FPXRF technology as part of the grade control function and concludes that FPXRF can provide operational and cost benefits to certain mining operations.

Jan 1, 2003

By Reimer TH

The model described in this paper has been developed for and in close collaboration with the Bong Mining Company Ltd, Liberia/West Africa. When working an irregular deposit a de- tailed short term production schedule becomes necessary in order to ensure an equal and homo- genous concentrator feed. If the irregularity of the ore body exceeds a certain degree, blen- ding facilities have to be provided between the mine and the concentrator, but even then sche- duling of the mine production is inevitable to meet the given requirements of the blending bed and to keep these conditions steady for at least some of the successive periods. To assist the planning department in set- ting up optimal production schedules a computer model has been developed using a linear pro- gramming approach. The deposit is divided into equally shaped blocks containing defined quali- ties and quantities of ore and/or waste; from which one has to select those quantities of ore which will meet the requirements of the blen- ding bed. The objective function of the model

Jan 1, 1977

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 Kennedy B. J

The 1100 Orebody is the main copper production area of Isa Mine with an output of 390 000 tonnes per four week period and a work force of approximately 260 men per shift. Currently a total of 56 nippers work a three shift, five day week roster to-service crews spread over a strike length of 1000 m and a vertical height of 220 in. A variety of rail and diesel equipment provides shaftto cribroom and cribroomto sublevel work place transport of men and materials. Overall eficiency and safety has been improved with a selected group performing supply, storage, clean-up and "bus runs" throughout the orebody - activities which are further co-ordinated by an FM radio system linking units with a control clerk.

Jan 1, 1977

By P O. Andersson

Mining of sill pillars is more difficult than the ordinary mining. The sill pillar mining is performed under more difficult conditions and the mining of the sill pillar itself produces more problems; failure of the rock due to high stresses, difficulties in controlling the fill above, overall stability of the stope and special requirements on the technique for backfilling. Altogether this makes sill pillar mining technically difficult and often not profitable. A project was therefore initiated with the aim to increase the mineable ore reserve by making sill pillars mineable, both technically and economically. The project aimed at developing technique for already existing sill pillars as well as planned sill pillars. For the existing sill pillars a technique would have to be developed for mining beneath unstabilised fill. For sill pillars that would be created in the future, the most suitable mining method and methods of supporting or stabilising the fill in the stope above was to be chosen within the project.

Jan 1, 1998

Accounting for borehole damage in analytical modelling of explosively generated stress waves is important for predicting the finer details of the stress wave patterns observed in the field. The classical Sharpe's [19421 concept of an effective borehole larger than the initial borehole diameter has been widely accepted to explain material damage around a borehole. A new analytical model based on dynamic compaction is advanced to predict far-field stress wave patterns. This model supports field data corresponding to reduced frequency of oscillations and increased damping. The present model recovers the earlier result when compaction around the borehole representing borehole damage is ignored.

Jan 1, 1990

By Upfold RW, Nguyen VU

The extraction and utilisation of metals and materials is the basis of modern civilisation, and will remain so for many decades, Traditional metals are facing some challenges and research is needed in specific areas, to improve metal extraction processes, to develop processes for newer metals and minerals, and to develop new applications, The shortage of metallurgists now becoming apparent in Australia is a further significant problem that needs urgent attention, and much more publicity is required for the Mineral Industry, as well as for the utilisation Industries,

Jan 1, 1986

By Sturgul J. R

ZC Mines investigated a proposal to replace the present underground train haulage system with rear dump trucks. The number of rear dump trucks required to achieve target output and the required mix of trains and trucks during the changeover was of importance to the designers, and a GPSS computer simulation model of the operation was constructed using GPSS/PC, a recent form of the language for the personal computer. Three models were 'constructed to simulate initial and final configurations of underground haulage systems to transport ore from ore passes to the crusher and then to the skip for transport to the surface. The initial model simulated train operation on two levels and rear dump truck operation on a third level. The second model simulated rear dump truck operation on two levels with ore being loaded through the crusher to the skip as in the previous case. The third model replaced the rear dump trucks on the lower level with a train to establish the relative merits of the two methods of transport. The simulations identified equipment numbers, required operating hours and critical points in the operation which can then be addressed by the mine designers.

Jan 1, 1988

The application of new and currently practised mining techniques in new areas and at greater depths necessitates considerable and immediate research effort. This effort is aimed at identifying the factors which make a particular method suitable and economically viable in a given geological, structural and operational environment. These factors, together with greatly enhanced knowledge of a deposit at the exploration and planning stage, allow selection of the most appropriate and efficient mining method in a new area such that coal resource recovery is maximised in a cost effective manner. Current research and future requirements for research into mining methods and associated equipment and mine services are reviewed.

Jan 1, 1981