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THERE is available a considerable amount of literature concerning the practice, and, to a smaller extent, the theory of ventilation as it applies to coal mines. Publications considering the subject of ventilation of metal mines from a practical viewpoint are much less numerous, whilst the treatment of the theoretical aspect of the question (except in so far as is common to coal mining) appears to have been almost neglected. This may be due to one of two causes (a) That in many metal mines (especially those which have not attained a great depth), on account of the greater number of connections with the surface, as compared with coal mines, natural ventilation has sufficed.(b) That in metal mines where the foregoing is not the case the solution of the ventilation problem from theoretical considerations has been regarded as involving so many complications that any attempt at the determination of a set of concrete ventilation figures applying to and throughout the mine would be futile. Whilst it is freely admitted that the difficulties inherent in the application of theory to the ventilation of metal mines are numerous, it must also be admitted that few attempts have been made to overcome them. The ultimate aim, of course, would be the collection of sufficient data to enable the probable behaviour of the air-currents throughout the whole of the workings of any mine to be accurately predicted under any particular set of circumstances. Failing the attainment of this goal of perfection, it would at least appear that much valuable information might be obtained. In ventilation, as in...

Jan 1, 1921

By Selby J

South Australia's economic development has relied heavily on the mineral industry. In the late 1840s the rich copper deposits at Kapunda and Burra saved the Colony's economy when South Australia became a world copper producer. Copper lodes developed at Moonta-Wallaroo during the 1860s brought further prosperity when mining activities at Kapunda and Burra were in decline. In addition to those large mines there were many smaller workings scattered through the Flinders and Mount Lofty Ranges producing copper, gold, silver, lead and zinc. Most of the mines of this period were worked by Cornish immigrants who brought their own technology and mining methods with them. These people have left a cultural legacy unique in Aus- tralia. In this Jubilee 150 year (1986) the Department of Mines and Energy, working in conjunction with the Department of Environment and Planning, is helping to preserve and interpret selected historic mining sites, most of which have been neglected since their closure. This work is designed to draw people's interest to mining history by providing interpreted sites for them to visit and to demon- strate the importance of the mining industry in South Australia's cultural and economic develop- Ment.

Jan 1, 1987

Human creativity springs from the natural desire of mankind to know and its capability to learn. Explorers and discoverers possess these features in a high degree. They are driven by an unrelenting curiosity to go beyond the boundaries of the known, to explore into the nature of things, to reveal connections between ideas, facts, conceptions, to view things from new angles, to change perceptions. A well-known fact about the construction industry - and underground construction in particular - is that all projects are unique. The degree of complexity due to the intertwining of the variety of project-related parameters is higher than in many other industries, thus forcing contractors as well as suppliers to be truly adaptable and flexible. The enormous advantages of shotcrete as a construction and rock support process and the improvement of materials, equipment and application know-how have made it a very important and necessary tool for modern underground construction works. The development of modem wet shotcreting in particular has enlarged the field of underground construction work. Projects that were impossible to be realised, have now become practicable. Subsurface structures can be placed where they are needed, without regards as to rock and soil conditions.

Jan 1, 1995

By Bradley AJ

Hamersley Iron Pty. Limited mines and pro cesses iron ore from two orebodies at Tom Price and Paraburdoo, situated in the North West of Western Australia. Conventional open pit mining methods are used at both sites in that material is drilled and blasted in benches, loaded by shovels and hauled to the Primary Crushers or dumped on waste or low grade material stockpiles. The present drilling fleet, consisting of eight high capacity Bucyrus Erie Rotary drills has evolved from an initial fleet of a large number of small percussion rigs. There are significant physical differences between the ore types encountered at both mines which nec- essitate the drilling of smaller diameter blast holes at Paraburdoo than those at Tom Price. The drilling practice at each site is dis- cussed, with examples of performance achieve- ments under varying drilling conditions.

Jan 1, 1978

The intent of this address is to look forward into the 21st Century and present certain thoughts as to how underground coal mining might be conducted. The views in this talk are based principally on the author's experience with mining practices in the United States. It may be difficult to accept, but the 21st Century is a mere 12 years away. What new techniques will be available? To develop an understanding of the way in which technology has been and could be changing, a two- stage analysis is made of mining technology for U.S. Coal. The first phase covers the period 1975 to the present, while the second includes 1960 to 1975. This historical perspective includes a view of underground production by mining methods, considerations of labour productivity, and a review of accident and fatality rates. Several topics are important features of this historical analysis. Among the most significant are: (1) the introduction of Ion-wall mining technology into U.S. underground coal mines, (2) the use of computers to assist in mine planning and design activities, (3) major efforts to improve health and safety performance, with emphasis on underground dust control, and (4) improvements in mining equipment with an eye towards increased reliability and up-time performance. Based on that historical perspective, projections are made in three increments. The first being immediately at the turn of the century, the second being a dozen or so years beyond that, and the third being at the quarter point of the 21st Century.

Jan 1, 1988

The recent trend of installing flotation cells with volumes as large as 200 m3 in concentrators is driven mainly by economic considerations such as lower capital, operating and maintenance costs. Despite the economic advantages, the metallurgical benefits from these large cells have not yet been fully realised by the industry. This is mainly due to the lack of understanding of cell operation, viz cell mixing and hydrodynamics, gas dispersion and froth transportation behaviour in large cells. There is still no rational basis for selecting optimum cell operating conditions and down-the-bank operating profiles. The relationship between cell operating conditions and metallurgy is not well established. This has resulted in poor utilisation of cell capacity in many operations. The present trend of installation of fewer cells in a bank requires each cell to be operated very efficiently. Optimisation of cell operation provides an opportunity for significant metallurgical improvements in a flotation circuit with minimal capital expenditure. Extensive work on optimising of cell performance has been carried out at various Teck Cominco operations in Canada, Peru and USA. Three different levels were involved in this work. The first level was aimed at identification of cell operating conditions for optimum mixing and hydrodynamics, gas dispersion, entrainment and froth flow behaviour in individual cells. The objective of the second level was to identify the optimum bank operating profile for cells down the bank in a circuit. The third level then focused on controlling these cell operating conditions and bank operating profiles for tighter control of concentrate grade and recovery for optimum bank metallurgy. This paper presents some of the major findings at all three levels and demonstrates the importance of each level in optimising the performance of flotation banks installed with large cells.

Jan 1, 2005

By T Martin, M Martin

Mining of sulfide-based ore deposits typically creates a potential for release sulfate and acid to groundwater, and many operating mines are thus predicted to require long-term post-closure treatment of groundwater. Toward the goal of selecting an optimal treatment, this paper compares costs of four demonstrated technologies for long-term treatment of sulfate-contaminated groundwater: in situ biological reduction (ISR), in situ permeable reactive barrier (PRB) composed of compost and zero-valent iron (ZVI), and two ex situ æpump-and-treatÆ technologies ù ex situ biological reduction, and ex situ nanofiltration with lime precipitation. Costs for each technology are estimated for treatment of a model aquifer system containing sulfate-contaminated groundwater, with the goal of treating 1 m3/min of groundwater from 1500 mg/L sulfate to a target level of 500 mg/L. (Metal removal is typically achieved by these technologies, and thus excluded from this analysis.) Costs are estimated for each technology as a function of treatment duration (ten to 60 years) and, for PRB and ISR, required replacement frequency (ten to 60 years). Estimated costs include capital and operation and maintenance, using a seven per cent net discount rate. Results indicate that ex situ technologies (biological reduction and nanofiltration with lime precipitation) are the most expensive. In situ technologies may be much less expensive, with PRBs having by far the lowest potential cost, followed by ISR as the next least expensive. However, actual costs for the in situ technologies are very sensitive to poorly constrained parameters, particularly the ZVI content of the PRB, and the effective life of PRB and ISR systems. This large cost uncertainty supports delaying remedial actions where viable, and suggests that feasibility analyses are generally warranted for specific applications to focus on these sources of uncertainty.

Jan 1, 2003

Computer software has been developed to link real-time information generated by underground mine ventilation airflow monitoring sensors into a network simulation program to undertake network simulations and allow interpretation of key system data and operational changes. Results were used in the development of a computerised monitoring and simulation system to provide immediate or real-time data on air behaviour within each branch of an underground mine ventilation network through linking of sensors to the ventilation network simulation software. The outcome of the project is an online system that can report changes in the mine ventilation system, allow causes of changes to be isolated and rectified, improve balancing of available air throughout the mine, allow improved approaches to regulator setting and dispense with much of the labour used for underground ventilation measurement. The work activities in both coal and metalliferous Australian mines have involved examination and modelling of regulators, software modification and considerable mine site testing and optimising activities. There is some discussion on approaches to control of flow through ventilation systems with increased information. New systems will be part of a total mine information management system. They will have to be cost effective and justified by gains in productivity. New systems will need to provide simulation of contaminant production such as diesels, vehicle heat, strata heat, radiation, blast fumes and other gases. More robust real-time ventilation simulation systems will be required. Personnel and vehicle identification and production tracking will be collected to provide integrated ventilation system monitoring and control. This paper examines a study to gain greater understanding of computerised real-time airflow monitoring and control within the mine production system to provide immediate simulated information in each branch of an underground ventilation network and to allow interpretation of key system data and operational changes. A case study implementing a real-time airflow monitoring and control is discussed. Approaches to control of flow through ventilation systems with increased information are discussed. The concept of a system that can be linked to or be part of a total mine information management system is developed. Such a system can form the base for mine automation that allows mines to incrementally and cost effectively implement monitoring and control to further seek gains in productivity.

Jan 1, 2005

By P Rubie, J Russell

This paper looks at the past, present and not too distant future of grinding mill relining.Since the adoption of autogenous grinding (AG) mills and semi-autogenous grinding (SAG) mills as the primary ore reducing devices in the comminution circuit, plant shutdown frequency and duration has largely been driven by the liner maintenance requirements of these mills.The past 30 years have seen the introduction of many technologies to reduce relining times and frequencies. Advanced relining systems have been developed which include single and twin Mill Relining Machines, capable of placing large (up to 8000 kg) liners, high energy recoilless THUNDERBOLT Hammers, and high capacity Feed Chute Transporters. Despite these advances, today many of the hazards associated with mill relining remain and reline times still vary considerably between mine sites. A sophisticated discrete event simulation program, designed to analyse the mill relining process, has revealed the dominant influences on reline times of crew performance and of the need for safe access to larger segments of the mill.A new generation of advanced and semi-automated technologies is currently being tested that will address these remaining challenges. These technologies remove people from the hazardous environment inside the mill and will allow techniques used in modern advanced manufacturing to provide a near-future step change in mill relining safety and performance.CITATION:Rubie, P and Russell, J, 2018. 21st century relining – the path to greater mine site profitability, in Proceedings 14th AusIMM Mill Operators' Conference 2018, pp 621–640 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018

By Kennedy JT

This is a question that will be asked many times and by many individuals during the various evaluation stages of any new project. However, the question itself will often have different connotations to the different groups invariably involved in such an exercise. As examples, consider just three of the several different groups involved in the development of a new mining project - Financiers, Consulting Engineers and the Sponsors of the project (potential borrowers). To the Financiers, a 'bankable project' will be one against which they will be prepared to lend funds (but not necessarily all of the funds requested by the Sponsors). This usually means that in the first instance the technical information presented to the bank has satisfactorily covered all of the requisite areas to the levels of accuracy required. More importantly, the financial evaluation of the projected economic performance of the mine, as a whole, is considered sound and a set of arrangements under which the bank is prepared to advance loan funds have been structured which fully satisfy the bank's credit criteria. To Consulting Engineers preparing a feasibility study (or a part thereof), on behalf of the project Sponsors, the term 'bankable' invariably only refers to the technical completeness and the level of detail contained in the report which they are preparing. Their scope of work will not necessarily have been broad enough to fully satisfy a bank's requirements. It is unusual to see any specific references to overall project viability or profitability in Consulting Engineers' feasibility reports, other than those which are automatically associated with the use of the term 'ore'.

Jan 1, 1990

By Govett G. J S, Currie D. A, Cohen D. R

Analysis of mechanical size fractions of soils around the Paddington deposit (W.A.) and the Charters Towers Goldfields (Queensland) shows a bimodal gold distribution, with enrichment in the coarsest and finest fractions; this is probably a common feature of soils in arid terrains. To establish the true distribution of Au within the soil fractions, the effect of bulk Au content and percent weight variations in size fractions can be reduced by a normali- zing procedure. The greatest extent of lateral dispersion of Au recorded in the -125 ¦m fraction at Paddington and the -63 ¦m in the Charters Towers area as compared to the coarser fractions, and increas- ed levels of sample representivity in the finer fractions, favours their use in exploration. If orientation studies indicate the preferen- tial use of coarse or intermediate fractions, only wet sieving can quantitatively dis- aggregate the clays and remove finer contamina- ting material. The collection of extremely fine fractions such as the -63 ¦m is also accelerated by wet sieving. The additional costs of wet sieving may be offset by better interpretation of results through increased analytical sample representivity, anomaly contrast and continuity.

Jan 1, 1988

Access roads for haulage, construction or maintenance purposes are discussed with particular attention being given to the un- sealed "all weather" form of construction for Off-Highway applications. The service conditions experienced by the surfaces used in these roads is examined. These conditions are discussed in terms of the conventional engineering properties used for natural gravel material selection. Experience gained during the construction of a pipeline access track is used to illustratE material selection guidelines based on geological input and an understanding of good construction practices. TMITDnIll IrTT Ohl In many Australian situations off-highway haulage by wheel or track supported vehicles is carried on unsealed, gravel roads. Although the unsealed gravel road is the back-bone of the rural road network in Australia, in general, traffic loadings are relatively low compared to the off-highway unsealed haulage road. The cost of the haulage/access road construction component is one important factor in project planning which needs careful consideration. It is no longer acceptable that the initial rough exploration track be gradually upgraded so that it will eventually carry construction and maintenance traffic safely and efficiently. Fatal accidents and

Jan 1, 1982

Average annual growth in consumption of primary energy in Australia over the past ten years has been 5.5% compared to a world average of 4.1%. Over the next ten years growth rate is expected to increase to 6% per annum due largely to the rapid development in the mineral processing industry. By the end of the 1970's natural gas is expected to supply more than 9% of Australia's, primary energy market. Coal will supply 40% and petroleum products 47%. Nuclear energy will make its appearance but-will only make a small contribution in the period. Australia has adequate reserves of natural gas and coal to supply its needs in the 1970's and beyond. However the newly developed reserves of crude, while supplying 60-70% of requirements-in the initial years; will need regular and sizable additions if they are to .keep pace with the expanding consumption. For Australia to become self sufficient in the period 1970-1990 it is estimated *that new discoveries-will need to approximate. ten times the volume of recoverable reserves found in Australia to date. .

Jan 1, 1970

This paper attempts to put into perspective the implications of the legal disclosure requirements for promoters and consultants when making statements concerning ore resources and reserves. The need to take account of non-technical as well as technical factors is highlighted.

Jan 1, 1987

The Musselwhite mine, located in northwestern Ontario, Canada, has been an underground narrow-vein gold producer since the spring of 1997. As an exploration project at the feasibility stage, much effort was undertaken to generate a geostatistical resource model that would integrate the orebodyÆs geological features, as well as the controls on mineralisation. Today as an operating mine producing over 200 000 ounces of gold per year, reconciliation studies of the tonnes and grades treated at the mill, with the feasibility model, for longer time periods, and with the grade control models, for shorter time periods, show results that are in good agreement. It was clearly demonstrated with the reconciliation to production, that the key to good reconciliation remains in the proper selection and application of the geological resource estimation method. The application of a grade interpolation technique capable of capturing threedimensionally pertinent geological features, as well as accounting for spatial grade continuity, proved to be successful in the predictability of tonnage and grade at the Musselwhite mine. Along with good mine practices, this approach, which was carried through to the operation, has produced excellent reconciliation results. The ongoing reconciliation studies at Musselwhite allow for a constant revision of the grade estimation strategy. In return, this optimisation process adds value by raising the accuracy level of production expectations. As this is an evolving practice at the mine site, further implementation developments are recommended to integrate these reconciliation procedures on a more regular basis.

Jan 1, 2002

Production of oic at BHP Minerals Pty Ltd's Cannington Mine commenced in May 1997. The initial sloping blocks at the [nine are located in the upper part of the Footwall Lead lode, and the Hangingwall Lead and Glenholme Breccia lodes. This paper discusses the geological investigations, interpretation and modelling that was undertaken for the Footwall Lead lode production block at Cannington Mine, as well as providing a basic geological introduction to the Cannington deposit.

Jan 1, 1997

Asbestos is a commercial term applied to fibrous varieties of several minerals, the properties of which are not generally appreciated by the majority of geologists. A thorough knowledge of these properties and of the uses of asbestos is of fundamental importance in the assessment of the economic value of an occurrence of asbestos. The varieties of asbestos that are used predominantly by the manufact- urers of asbestos products are chrysotile, crocidolite and amosite but chrysotile constitutes 95% of the world's usage. It is the properties of high tensile strength, 'heat resistance and large surface area that make chrysotile asbestos the most acceptable of the mineral fibres. There are no known exploration aids, other than direct visual inspec- tion of outcrops in ultrabasic environments, that could be used in the exploration of chrysotile asbestos. The surface exploration of an occurrence of chrysotile asbestos is relatively routine, though it lends itself to a unique form of bulk sampling by the use of a twelve inch diameter diamond drill core. The laboratory assessment of the prop- erties of the actual fibre requires specialized techniques and tests to assess not only the amount of fibre present but also its length distri- bution, inherent strength, filterability, dust content and other prop- erties. The way a fibre reacts to milling will determine what milling process- es must be implemented to ensure a product that is acceptable to the asbestos product manufacturing industry.

Jan 1, 1971

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

A major problem with many items of underground equipment is that they have either been converted or adapted from surface equipment, or that they have been designed and assembled in comfortable offices and factories with adequate lighting, specialised tools, and ample space. As soon as they are in use underground in cramped spaces maintenance frequently becomes difficult, parts are awkward to change, and a whole range of accidents can happen.Similarly, ingenious operators discover a whole range of uses for which the equipment was not designed, such as using a loader bucket for a work platform, or scaling backs with it.Design modifications of equipment and removal of hazardous components that can trap limbs is expensive when the dangers are discovered in operation, sometimes posthumously, and it is not surprising that workers compensation insurance premiums are high. The cheapest place to ensure that equipment is safe is in the design office, where the operator should be considered first, rather than being added to a purpose built machine as an afterthought.

Jan 1, 1992

This paper describes a steam outburst in a metal mine which occurred in December 1992 in Japan, resulting in two fatalities. The outburst occurred just after blasting in a heading face 600 m below surface (SL-50 m), 1664 m from a mouth of the mine. The scale of the outburst was large and the fragments of the outburst spread up to 34 m from the face, the total volume of the outburst was estimated to be 206 m3. The outburst materials were mostly clay originated from the typical surrounding rock of sulfide ore and basalt. The shape of the larger outburst fragments were slabs with a thickness of 10 to 20 cm. The victims were found in a main ventilation air shaft, 175 m and 380 m from the face, respectively. The mine mainly produces copper, lead and zinc. The face was ventilated by a 560 mm diameter duct with a fan and the strata temperature of the rock was estimated to be in the range of 120 to 140¦C. There is a famous hot spring near the mine. A thorough investigation into the unprecedented accident was made including an on-site inspection and investigation of rock characteristics in laboratories.

Jan 1, 2005