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By Dorricott M. G

Rock bolt installation is generally carried out in two steps. First the hole is drilled and the drill steel is extracted, then the bolt is inserted into the hole and tightened or grouted. With single pass bolting (SPB), however, these two steps can be carried out at the same time. This kind of bolting system has at least three advantages, (1) the time used for the bolt installation could be reduced, (2) the condition of safety for the operators could be improved, and (3) the degree of automation of the rock bolting practice could be increased. The study presented in this paper is concerned with the development of the SPB system. The current state of the system is discussed, and further improvement of the technique is explored.

Jan 1, 1992

The energy input requirement to produce the molten slag associated with iron production to the modern Australian blast furnace, is estimated to be 2.OMJ/kg. In converting blast furnace slag to products of higher commercial value, advantage should be taken of this energy content by transporting molten slag from the furnace for beneficiation and processing in the molten state at an "off furnace site". The refined slag melt may then be converted into a variety of products for use in the building and construction industries, e.g. slag cement, slag sand and slag aggregates, insulation wool and various slag ceramic products. Some results of studies into slag melt beneficiation and conversion processes involving both molten and cold granular slag raw material, are presented.

Jan 1, 1979

The granitoid rocks in Burma can be subdivided into three main belts viz. (1) Eastern Granitoid Belt, (2) W-Sn related, Central Granitoid Belt and (3) Porphyry Cu (Au)-related, Western Granitoid Belt. The W-Sn related, central belt Granitoids were interpreted to have generated during the continent-arc collision and the Porphyry Cu(Au)-related, western grantioid belt was emplaced in a magmatic-volcanic arc above an east-dipping subduction zone. INTRODUCTION Major tectonic domains of Burma Burma region can be subdivided into N-S trending (6) major tectonic domains from west to east (1) Arakan Coastal Strip as ensimatic Foredeep (2) Indo-Burman Ranges as Outer Arc or Fore Arc (3) Western Inner-Burman Tertiary Basin as Inter-Arc Basin (4) Central Volcanic Belt (Central Volcanic Line) as Inner Magmatic-volcanic Arc (5) Eastern Inner-Burman Tertiary Basin as Back-Arc Basin and (6) Shan-Tennasserim Massif as ensialic, Sino-Burman Ranges (Bender, 1983). The Sagaing (transform) Fault and Shan Boundary Fault form as a tectonically significant boundary between Eastern-Burman Basin (Back-Arc Basin) and continental,

Jan 1, 1987

A new classification of subduction related (epithermal- / mesother-mal) gold mineralisation styles based on the tectonic framework they occur in, has been found helpful in practice. It offers a ratio-nalisation of exploration efforts during all stages of work.Methodology on the ground during first pass- and follow up explo-ration which has been found effective for the various mineralisa-tion styles is being briefly outlined.

Jan 1, 1990

Two continuous computer controlled, remote air analysis (RAA) systems operate at The Zinc Corporation, Limited (ZC) to give early warning in case of an underground fire at ZC or New Broken Hill Consolidated Limited (NBHC) mines. Air drawn from underground sampling points via a tube bundle system is analysed for carbon monoxide and carbon dioxide. An alarm is sounded if the concentrations of these gases exceed bench mark figures.

Jan 1, 1983

By Coronel PT

Like companies in other sectors of industry, mining companies are experiencing significant problems with low labour productivity, high labour turnover, and accidents. Increasingly, companies are recognising that good training is a vital factor in dealing with these problems. One such company is Aberfoyle Tin Limited. Early in 1979 the company engaged P.A. Consulting Services Pty. Ltd. (P.A.) to upgrade and formalize its miner training procedures. P.A. developed a programme using their Process Analysis Method of Training (P.A.M.T.) and trained a company trainer in its use. As a result of its application and the establishment of a formal training school, the rate of production of trained miners has been greatly increased. Despite some problems caused by lack of resources at the mine, the trainees graduating under the new scheme have been shown to be of comparable standard to those produced by the previously used "on the job" training method.

Jan 1, 1980

By Avraamides J, Ritchie I. M

Gold Tellurides are important sources of gold at Kalgoorlie, Western Australia, Cripple Creek, Colorado and Vatukoula, Fiji. Unlike free gold, the tellurides of gold are rather refractory and the usual treatment practice has been to oxidize the tellurides, either chemically or by roasting prior to cyanidation of the liberated free gold. There is a large measure of disagree- ment as to the actual cause of the refractory nature of gold tellurides. In order to investigate the leaching chemistry of gold telluride, a study was undertaken on the thermodynamics and kinetics of its dissolution using electrochemical methods. From this study suitable direct leaching condi- tions are suggested. In acidic chloride solutions gold telluride can be leached using iron(III) as the oxidant. At lower acid concentrations the reaction is controlled by the formation of a passivating film of H2TeO3. In alkaline solutions containing cyanide the rate of gold telluride dissolution increases with increasing pH and strength of oxidant. However, this can result in excessive consumption of cyanide in the presence of stronger oxidants.

Jan 1, 1991

By W Schauenburg

The increasing problems associated with the disposal of waste and the potential for use of by-products as underground filling material is a subject which is relevant not only to the coal-mining industry. The progressive scarcity of surface disposal facilities for by-products and waste has now become a problem in all sectors - not only for the mining industry. The considerable capacity offered by underground cavities which exists in various mining branches present an extremely promising potential in this context. The backfill process for coal mining developed by DMT in co-operation with Ruhrkohle AG make use of the cavities which are offered by the extraction of coal. It consists of several stages: The fine-grained by-products, such as sludge, filter cakes, fine refuse, ash and flue-gas cleaning residues are processed on the basis of specified formulations in metering, blending and pump facilities on the surface to produce pumpable pastes with precisely defined flow characteristics. On Walsum Colliery of Ruhrkohle AG up to 200 m3/h stowing paste is conveyed into the mine in pipes with diameter of 200 mm (8"). The delivery pressure of the pump operating on surface in conjunction with the hydrostatic pressure of the shaft pipe - amounting in total to as much as 25 MPa - makes it possible to convey the stowing material for a distance 12000 m underground up to the workings without any need for additional booster pumps. Via a pipe installed in the face, the paste is pressurised into the cavities in the specially fragmented rock in the mined-out zone well behind the support. Consistent use of stowage of caved-in goafs makes it possible to reduce surface settlement above the workings. Fires in the stowed rock are either smothered or completely prevented thanks to the exceptional air-tightness in the caved goaf and the cooling effects of the slurry stowage. The reduced danger of fire, the preventation of air-leakage and the positive effects on gas emission from the coal improve safety in the workings.

Jan 1, 1998

By C A. Fleming, C J. Ferron, P T. OÆ

A new process is described which allows for direct recovery of base and precious metals (Au and PGMÆs) from sulphide concentrates or other feedstocks. The process was developed initially for application to ores or concentrates that are too low-grade for economic treatment by the conventional smelting and matte leaching process (for PGMÆs). It is now believed that the process may be widely applicable to a variety of materials including PGM concentrates containing high amounts of chromium or magnesium. Operating conditions have been identified under which gold, the PGMÆs and the base metals dissolve simultaneously in a pressure leaching autoclave. The product of this leaching process can then be treated by one of several flowsheets, of which the preferred will likely involve solid/liquid separation, followed by precipitation (or adsorption on activated carbon) of gold and the PGMÆs, followed by copper solvent extraction/electrowinning. Depending on the concentrations of nickel and cobalt, the copper raffinate would either be partially recycled to the autoclave to allow Ni/Co concentrations to build up, or it would proceed directly to a Ni/Co refinery. This paper deals with the pressure leaching process and the recovery of gold and the PGMÆs from the pressure leach product.

Jan 1, 2000

While South Africa is well endowed with mineral resources, it is generally accepted that its future will be determined more by the development of its human resources than its mineral wealth. The country has throughout its modern history suffered from an over-supply of unskilled labour and a shortage of skilled and professional manpower. There has furthermore always been an over-reliance on Whites as an internal source of professional manpower, supplemented by immigration wherever possible. Better utilisation of other population groups in professional positions has been hampered by the general lack of education and training among such groups. Although many problems still remain, there are emerging trends which are likely to positively affect the training of professional manpower in the future. The direct and indirect influences that are likely to affect professional training at the macro level include 1. government policy and objectives in respect of manpower education and training, 2. the emergence of technikons as fully- fledged tertiary education institutions, 3. demographic trends in South Africa as they pertain to education, 4. political and statutory developments in the country, 5. industry involvement in tertiary education, and 6. professional registration.

Jan 1, 1986

The needs for improved technology for the mineral industry are widely recognised and a summary list is given. Ways in which technology has been introduced into the industry are discussed, as are the means by which the general process of technology transfer takes place. Some possible sources of improved and new technology are considered, together with the constraints to its introduction into the industry. Responses to recent external influences on the industry are discussed in relation to their effects on technology development.

Jan 1, 1986

One does not need to travel too far back in time to find that the manpower requirements for new projects were focused mainly on: ò plentifulness of supply; ò cheapness of use; and ò fitness for use. These were primarily quantitative considerations and corresponded with the dominant view of labour as a commodity. Qualitative considerations were not very evident with the exception of judgements of industrial militancy. It was not unusual for areas of known militancy to be excluded from the recruitment net (eg Captain's Flat, Broken Hill, Pilbara).

Jan 1, 1991

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

The new field of environmental investiga tions introduces new problems of ethics, res- ponsibility, conflict of interest and technical procedures. Such investigations involve four elements: developer, consultant, approving authority and the public. It is essential that the consultant provide technical competence, speed and efficiency, impartiality and credibi- lity. Despite allegations to the contrary, it is not in the consultant's own best interest to omit, ignore or obscure significant adverse en vironmental impacts.

Jan 1, 1975

By D L. Kennedy

Many aspects of the physical layout of manufacturing plants and storage facilities for explosives are governed by so-called quantity-distances tables. Both the British and the American tables were originally derived from an analysis of the injuries and the building damage documented by an early 20th century compilation of significant accidental explosions. However, progressive changes in explosive process technology and in building techniques have reduced the relevance of much of this historic data set. Extensive scientific research has been conducted over recent decades to characterise the potential injuries and damage from accidental explosions under more modern conditions. This presentation will showcase some of this research.**This is an abstract only. No paper was provided for this abstract**

Nov 8, 2011

DIVERSITY There are plenty of examples to show that diversity has been the fundamental downfall of many organisations, particularly when you consider the international position. What about core business, the return of companies to key competence directions and market focus. The stockmarket for instance defines groups and companies in key groups of core business. The expectation is that companies toe the line and do not diversify across their areas of defined expertise. In essence, the market has given notice that the requirements are to focus and stick to our core business. So what right does the conference have to suggest that diversity is the key to prosperity. Hasn't the organiser read the book, studied the history, listened to the market - obviously not. Have they got it wrong, My feeling and belief is no - the organisers have got it right. However, the matter is not as simple as first perceived. What is Diversity, or Diversification as I would prefer? Is it a product position? Is it a geographic position? Is it an expansion or change in services offered? Does a gold mining company diversify into copper or diamonds or aluminium or nickel? Does a gold miner in Australia diversify into China or Kazakhstan or West Africa? How do the two relate? They don't. A successful company will always possess a 'core competence' not so much a 'core business'. The best example of this is the service company extraordinaire - McDonalds. They don't sell hamburgers or french fries, they sell a service, a convenience, a lifestyle. The core business is hamburgers and if McDonalds were to diversify further into new styles of hamburgers, I suggest to you they would fail. But if McDonalds were to diversify into other products based on their 'core competence', provision of service, then I would suggest to you they would be very successful. The service procedure, service machine, service system, the formula, stava the rnnetant the nrnrlnrte -

Jan 1, 1996

The mobility of radionuclides released into aquatic, terrestrial and subsurface environments by mining, industrial processes is an area that deserves significant scientific attention. The presence of microorganisms in these environments can influence the transport of radionuclides. Free-living microorganisms constitute mobile suspended particles that may have a radionuclide sorbing capacity higher than that of the environment. Radionuclide transport will then proceed faster with than without microorganisms. In contrast, if the majority of the microorganisms are growing in biofilms on surfaces, transport of radionuclides may be reduced. Microorganisms can directly sorb radionuclides either within the cell structure or on the cell wall. Radionuclides could also be sorbed by minerals precipitated by microorganisms. Microorganisms produce complexing agents that can influence radionuclide mobility. The involvement of microorganisms in biogeochemical processes is related to their ability to include various chemical elements and their combinations into biochemical redox reactions. Microorganisms can alter the extent of radionuclide oxidation that results in their deposition as a result of the formation of insoluble forms. Some studies have shown the bioremediative potential of stimulating reducing bacteria to use some of the soluble radionuclides as electron acceptors and thus precipitate them out of solution. The microbial involvement in providing a barrier for radioactive element migration (uranium, technetium) and the formation of ores (eg uranium) has been justified. The mediated impact of microbial activity on radionuclide migration occurs through its effect on the ambient geochemistry by geochemical speciation changes, pH changes and changes to the ambient redox potential. As the mobility of many radionuclides depends on the pH and redox potential of the environment, these microbially mediated geochemical changes can influence radionuclide migration through changes to both the dominant radionuclide species and mineral phases.

Jan 1, 2004

By Sobek S, Lotzien RM

Although the conventional procedures for designing agitator flotation plants are well-known and reliable, little experience for designing modem pneumatic flotation plants has been gained up to now. A reliable procedure originating from graphic methods for the design of distillation columns is presented. Examples demonstrate on laboratory and semi-technical scale the application of this extremely practical method for designing a fly ash and a magnesite flotation plant.

Jan 1, 1993

Australian wheat belt agriculture is causing a decline of its natural resource base. The major problem, salinity, arises from a small reduction in water consumption by agricultural crops compared to what prevailed under the prior native vegetation. This causes groundwater accumulation which, in the low relief landscapes of the wheat belt, is leading to extensive surface saturation in low landscape positions and dramatic, destructive change in the hydrological behaviour and habitat of streams and rivers. The ability of agriculture to invest in salinity control is severely limited by its long-term decline in its terms of trade. Extensive planting of perennial vegetation has the potential to increase water use and arrest the salinisation process. If these perennials were also commercially attractive, the cost of salinity treatment could be minimised. Given the difficult commercial position of food commodities, it is logical to develop ænon-foodÆ perennial crops, in particular woody crops suitable for industrial products. This paper looks at the example of Sweden, where there has been a generation of investment in developing forest harvest residue recovery, and short cycle woody crops for bioenergy, but with only limited success. In contrast, secondary residues (processing wastes) from forestry industry are readily saleable for low value uses like bioenergy. This suggests that the model woody crop must have a higher value fraction to facilitate delivery and commercial use of its lower value fractions. This model is being emulated in the development of native mallee eucalypts as short cycle woody crops in Western Australia. Some $50 million has been expended on mallee development in the past decade and this has culminated in an engineering demonstration of integrated processing. The putative high value products are activated carbon and eucalyptus oil and the residue (plus waste heat) will be converted to electricity. The potential scale on which crops of this type would be required to achieve salinity control means that many more high value and residue products will have to be developed. Metallurgical charcoal appears to be a promising product option.

Jan 1, 2006

The effect of temperature, time and SO2 concentration in the atmosphate have been studied for a complex Pb-Zn concentrate, which contained four sulphides and some organic material, in order to determine optimum roasting conditions. Under static roasting conditions virtually complete sulphation was achieved after roasting at 650¦C.2 hours in 10% SO2 in air. Both zinc ferrite and zinc silicate were observed to form early in the roasting, but continued exposure to SO2 -containing gases caused decomposition of these as the roasting time increased. Water and acid solubilities of iron, silica, calcium, magnesium and aluminium in the calcine were determined, as a function of roasting time, temperature and atmosphere composition.

Jan 1, 1970