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The concentrated efforts now being directed towards the development and application of monitoring and control techniques have now resulted in their widespread use in UK mines together with evidence of benefits resulting from their application. There is little doubt that the longwall method of producing deep mined coal will continue but will be made more reliable and efficient with the aid of control technology. The major fields of research and development work are concerned with planning and design of mines and mining equipment; management and engineering information; and automation of coalface, tunnelling and transport systems. The principal achievements now in widespread use are: the standard computer system MINOS, widely applied to mine transport, coalfaces and mine environment; extensive use of machine condition monitoring leading to condition-based maintenance; underground automation of conveyor systems and guidance systems for ranging drum shearers and boom-type roadheaders are being widely introduced.

Jan 1, 1985

By C Gormley, G Lane, J Kwak, A Hopkins

Complex processing plants present a myriad of safety issues to the design engineer. The extent to which the design engineer manages to lay the foundations for a safe plant ultimately sets the stage for life long safety performance. Industry traditionally measures engineering safety performance by indicators such as Lost Time Injuries, Restricted Work Case Injuries, Overall Incident Frequency Rates, etc. While these measures are useful indicators of performance for the construction, commissioning and operations phase of a project, they do not necessarily drive the most appropriate behaviours for Safe Plant Design. Achieving an inherently safe design requires a diligent focus on low frequency, high consequence events. First and foremost the engineering team needs to have a design culture and methodology which leads to a plant which is as close as possible to being inherently safe. Such a culture might come from an organisation that has æmindfulnessÆ about safety, and which is nurturing a culture where warning signs are recognised and addressed. This paper explores the development of mindfulness and warning signs in design.

Jan 1, 2004

The Australian mining industry can expect to be working internationally competitive high quality coal mines during the twenty-first century. Cost efficient mining methods such as high productivity longwall units with heavy reliance on remote control will be standard and worked by well paid and intensively trained operators. Major changes in mine ventilation engineering can be expected in the use of computers and mine telemetry, the understanding of the mine environment and the frequency of mine disasters, the utilization of mine air contaminants for profitable purposes and the provision of a pleasant and comfortable work environment. New approaches to mine ventilation such as air recirculation will have been considered. There will be an increased need for highly trained ventilation engineers. With the present pace of technological change, quite revolutionary new approaches to mining and ventilation can be expected by the end of the twenty-first century.

Jan 1, 1988

By Scholl EW, Ricken W

The simultaneous presence of fuel, oxygen, and of an ignition source is necessary for an explosion to arise. If one of these conditions is missing an explosion cannot take place. A continuous reduction of oxygen, often applied as a protective measure in surface plants, is not to be considered for underground mining because of possible danger to persons. Therefore, measures for avoiding explosions can only be concerned with lowering methane and coal-dust concentrations to an undangerous level and avoiding ignition sources. As these measures alone are not sufficient, additional ones have to be taken to keep the effect of an explosion as low as possible. Measures for controlling and monitoring methane are essential. Although the formation of dangerous coal dust concentration cannot be avoided it can be reduced. Dust-binding by means of hygroscopic pastes and dusting with limestone dust are effective measures to pre vent explosions.

Jan 1, 1981

In Europe there are many regions, where coal or lignite is mined with surface methods. In most of these regions coal/ lignite is mined below groundwater table and mining opera- tions require pumping big volumes of water. Drawdown of groundwater table has influence on surface water and ground- water on adjacent areas. Mine drainage requires purification and its discharge changes flow in existing streams. Some of mine water is used by mining companies themselves, some is used by other industries, some for communal purposes and some for irrigation. However, majority of mine water is dis- charged to rivers without use. The above issues are discus- sed on the background of general, technical and water charac- teristics of such regions in B European countries. Conclu- sions and prospects for future complete the paper.

Jan 1, 1988

By Valenti M

A by-product of the lead smelting operations at BHAS is a copper-lead matte typically containing 35% copper, 38% lead and 12% sulphur. A hydrometallurgical treatment process has been developed for the treatment of this matte to recover copper as cathode and results in a lead-sulphur residue which is recycled to the lead smelter. A commercial plant with a nominal capacity of 4000 tpa utilising this process was commissioned during 1984. This plant has been shown to be capable of producing copper cathode at rates approaching 4000 tpa over short periods of time.

Jan 1, 1989

Leadership challenges for mine management over the next decade will be primarily about doing more with less labour. This will require a greater focus on people leadership and management, reducing uncertainty by evening out employment peaks and troughs, understanding and addressing our demographic destiny and its implications whilst identifying and holding onto our mission critical employees, managing creativity and accepting diversity whilst providing flexibility in employment for work-life balance. Greater emphasis will also be required on the non-technical social skills of complex interactions with community and education providers and finally a greater emphasis on forecasting and planning for the provision of future skills needs. Skills needs will become an ever increasing priority in risk management as retention starts with attraction and remember: SATISFACTION = REALITY                                EXPECTATIONS These are the challenges and opportunities for leadership and mine management of the 21st century to assist in better meeting and maintaining our human resources needs and thus contributing to the sustainability of the sector in Australasia.

Jan 1, 2006

By S A. Johnson, J Cassidy, J L. Mauk

Geophysical anomalies at Puhipuhi reflect both diverse lithologies and different degrees of hydrothermal alteration. Most significant is a strong negative gravity anomaly (up to 50 g.u.), encompassing but extending beyond areas of known alteration, which is modelled as a deep zone (up to 3 km) of reduced density in the host greywacke basement. This zone, interpreted as being due to alteration (at least in part), closely correlates with the extent of overlying basalt flows. The gravity data indicate that the most intense alteration occurs below the basalts and correlates with the location of previously inferred hydrothermal upflow zones. These observations suggest that the basalt may have acted as a cap rock to a mineralising geothermal system. Aeromagnetic data identify highly variable but typically low magnetisations in the basalts which suggests that alteration may have been contemporaneous with volcanism. These geophysical data at Puhipuhi confirm the locations of centres of known alteration and suggest potential exploration targets below the basalt cap where there is no surface manifestation of alteration. Further implications of these results are discussed in Locke et al. (1999).

Jan 1, 1999

I am sure that you are- all familiar with Airborne Magneto-meter Surveying so I shall-spend only a brief moment describing the instrument and techniques and the remainder of the allotted time-on-modern-application-of the instrument.The Airborne Magnetometer used by Aero Service in AUstralia-was designated by Gulf Research and implements the saturable-core flux-gate--principle. The first magnetometers developed'weremagnetic-balances and depended on the counter-torque principle but these required a stable platform and hence are not applicable to airborne surveying. Other methods include the induction methods, the Hall Effect methods, magneto-striction methods., Deflectioh. of,free.electrons, the proton-precession methods.Some: of these are applicable to airborne surveying. As a matter of-fact the nuclear precession magnetometer is the one generally used in the Satellites because it has been miniaturized most successfully.The Gulf Magnetometer is the one most generally used in mineral and petroleum exploration because its sensitivity is sufficient for the problem and-data and instrument techniques have been worked out and standardized.

Jan 1, 1962

The processes most likely to be adopted for beneficiating ores or concentrator streams containing a large proportion of particles finer than 10 um are froth flotation, selective flocculation, wet magnetic separation and selective leaching. Flotation will be made more efficient for very fine particles if ways can be found to selectively flocculate the valuable mineral beforehand (floc-flotation), to produce smaller bubbles and to reduce entrainment of ultrafine gangue. Schemes for selective flocculation have proved difficult to implement because of the delicate balance between surface forces (electrostatic, dispersion, hydrophobic) and hydrodynamic forces, that determines flocculation, and the changes which occur to particle surfaces through hydrolysis, oxidation-reduction and cross-contamination between minerals in aqueous suspensions. The search for a better understanding of selective adsorption of flotation collectors and flocculants continues and will be particularly important for the practical success of selective flocculation and selective magnetic coating.

Jan 1, 1986

By P Alspach, R Buxton, C Morgan, C Ross

Mining companies worldwide have an increasing interest in restoring indigenous ecosystems following mining. Low levels of plant nutrients and organic matter, pH extremes, heavy metals, physically challenging media, and difficult climatic conditions all hinder revegetation of steep rockdump slopes. Our techniques use colonising pioneer plants to accelerate natural soil development and plant succession processes on minesites that are difficult to revegetate with locally sourced plants by traditional techniques. Suitable treatments and pioneer species must first be identified for each rocktype. Field trials at the Stockton Coal Mine in Buller have shown that successful acceleration of moss and pioneer plant establishment is possible. Best plots showed a mean of 15 per cent moss cover and 3.3 per cent vascular cover after 12 months compared with 0.1 per cent and nil respectively for controls. Techniques have been extended to field-scale trials, using hydroseeders and dryblowers. These techniques show potential for practical land rehabilitation, whilst conserving local biodiversity.

Jan 1, 2003

During the 1960s chalcocite ore was mined from the Black Rock open cut. A large amount of this uneconomic material was not treated by the No 3 Concentrator at the time and as a consequence a surface stockpile was created which contained 750 000 tonnes of material at an average of 1.5 per cent copper.Laboratory trials indicated that due to oxidation, an average of 25 per cent of the copper was water soluble and the remaining copper was leachable using a sulphate/ferriclbacterial leach. On the basis of these trials it was decided to investigate the feasibility of producing copper via a leach SX-EW process. The investigation proved the process was feasible, so began the design, construction and commissioning of a 10 tpd (cathode copper) Copper Leach SX-EW Pilot Plant. CMPS Pty Limited in a joint venture with John Holland Engineering Pty Limited were awarded the turnkey contract for the design, construction and commissioning of the Pilot Plant.

Jan 1, 1993

Mount Isa mine is the largest underground mine in Australia and is located 2,000 kilometres north-west of Brisbane. This mine has been in continuous operation since 1931 and in 1986/87 the silver/lead/zinc stream achieved the peak annual mining rate of 4.7 million tonnes. At present about fifteen different steeply dipping stratiform orebodies are being mined to maintain an annual production rate of around 3.0 million tonnes. Out of these, only two orebodies (2 & 5) are amenable to sub level open stoping (SLOS) type bulk mining methods. This year only 150,000 tonnes are scheduled from pillars and remnant areas but in future, more sources will be required to meet the budget production targets.

Jan 1, 1990

Capital expenditure on sampling and blending is often very difficult to justify. The costs are easy to estimate but the benefits likely to be obtained by constructing good sampling and blending facilities are generally difficult to estimate. For instance, improving blending of the ore feed to a smelter would improve throughput, yield and controllability ... but by how much? Similarly, better sampling would allow processing conditions to be dynamically adjusted and would improve extraction ... but by how much? Predicting benefits often requires the use of simulation models which carefully distinguish between true grades, predicted grades and observed grades. The parameters of these simulation models must often be estimated from rather inadequate information. These difficulties are illustrated using three scenarios.

Jan 1, 2005

By E G. Thomas

"This paper details the many improvements possible in narrow vein mining from the use of treated mining/milling waste as mine fill. Such fill can be: treated mill tailing, cemented or uncemented; development muck, treated or untreated, cemented or uncemented; andsome combination of these materials, or surface sands/gravels. Treatments involved may be both physical (optimisation of particle size gradings) and chemical (neutralision of potentially harmful milling chemicals).Potential benefits include a reduction in: back stress; vein closure; alternate ground support requirements; mining dilution; potential for surface subsidence; and extent of surface disposal of mining/milling waste, resulting in reduced environmental impact. Considering the usually small production tonnages involved, preparation and placement of a highly applicable fill material can be economically accommodated.Emphasis is placed on steeply dipping orebodies being mined overhand, although practice in the much less steeply dipping RSA gold/platinum-type orebody is also considered.CITATION:Thomas, E G, 2012. Mine fill in thin vein mining, in Proceedings Narrow Vein Mining 2012 , pp 215-218 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 26, 2012

Inevitably the 'post-boom' era has changed the emphasis of many mining companies away from new project development and expansion to optimisation of existing operations. However, regardless of the project, high quality ore characterisation will remain of the utmost importance. In the case of new project development the need to understand the breakage characteristics will remain as important as it has always been. In optimisation projects, however, where it will be required to get the very best from existing comminution circuits, accurate geometallurgical modelling will take on an increasingly important role. However, these requirements, in both new development and optimisation projects, are likely to be at odds with budgets as these will be tight. Hence obtaining the best value for money will be essential. This paper discusses the elements that need to be satisfied for ore characterisation programs to be successful. Some of the issues covered will be: ore variability and sample selection, test precision, problems with the use of non-standard testing equipment, and the value of databases.

Jan 1, 2009

Geochemical investigations carried out in the Woodcutters area, Rum Jungle district, NT., consisted of a programme of C-horizon soil geochemical sampling followed by rotary-percussion and diamond drilling.Comparison of detailed geochemical sampling with the original broadly-spaced sampling showed that the structures along which the orebodies occur are reflected very closely by the detailed sampling.A series of vertical rotary-percussion drill holes put down adjacent to a gossan revealed a broad layered dispersion of lead and zinc in the deep lateritic weathering profile, while primary dispersion haloes are only very narrow. The layering appears to be related to the weathering profile.

Jan 1, 1978

By Sijing Cai, Chengpu Zhou

The requirement of mineral resources is increasing as the economy is continually increasing in China. The mining practices of various complex sulphide deposits and precious metal deposits, and the treatment of mine tailings and other industrial solid wastes, have greatly improved fill quality in the metal mines. From early-1980s, high density slurry fill, paste fill of total tailings, low density slurry fill with addition of silicate gelling agent, etc has been studied and applied, and some progress has been achieved. Today, mine tailings, slag and power plant ash are widely used as fill materials in mining. A number of cemented fill mines equipped with large capacity trackless mining machines are in production. Recently, The 3rd Chinese National Symposium on Mining with Backfill, 1995 has been held, the progress of fill technology in mines has been exchanged and summarised. In the paper, some aspects of fill technology used in the metal mines of China are briefly introduced and some applications of fill research work are presented.

Jan 1, 1998

IF lead be heated with concentrated sulphuric acid two distinct actions will usually be observed. In the first, bubbles begin to be evolved more or less rapidly from the lead, and in the second, which occurs at a higher temperature than the first, hydrogen and sulphur dioxide are evolved, free sulphur is liberated, and leadsulphate is formed. The second action may be violent and usually continues till the lead is all consumed.Attempts have been made to apply these reactions, by means of a standard procedure, as a "Flash test" for the acid resisting qualities of chemical sheet lead. The purpose of this article is to comment on the best method of performing the test, on the various phenomena which may be observed during the course of it and on the interpretation of the results when obtained.PREVIOUS WORKIn 1919, Barr...

Jan 1, 1930

Comalco's Bell Bay smelter produces some 94 000 t.p.a. of primary aluminium in the form of foundry alloys, extrusion billet and rolling blocks. The extrusion billet and rolling block are produced by a process, in which molten aluminium is poured into an open ended water cooled mould of the required shape. The bottom of the mould is initially closed off by a dummy or starting block. Primary cooling takes place at the mould wall and secondary cooling is achieved by direct water sprays onto the out side shell of the product. Careful preparation of the molten alumin- ium is essential if stringent alloy specific- ation limits are to be met. Optimum casting temperature must be maintained within a narrow range and metal cleanliness is important to ensure a consistent product. Increased demands of recent years for larger product and higher standards of surface quality and dimensional control have been instrumental in forcing improvements in furn- aces, casting machines and in mould and dummy Doq,

Jan 1, 1977