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Prediction of large-scale underground opening stability in quite complex mining circumstances is being undertaken on a routine basis at The Zinc Corporation, Limited, (ZC) and New Broken Hill Consolidated Limited (NBHC) Broken Hill, Australia. A three- dimensional numerical modelling technique has been developed that gives good correspondence with the observed behaviour in many stopes. New insights into the rock mechanics of under- ground mining are flowing from this work. The modelling practice can be taught to engineers in a reasonable time-frame. In-house computing facilities including graphics workstations are needed. The RMS software is designed to be user-friendly and very robust.

Jan 1, 1983

By D S. Stewart, K W. Keskimaki

In 1999, the Henderson Mine commissioned the Henderson 2000 project - a new truck haulage level, a new underground crusher and a 24 kilometre conveyor system to replace a 23-year old rail haulage system. Henderson has been able to continuously improve in almost all aspects of its rubber-tired mining. The rail haulage system represented one of the last barriers to continuous improvement to the overall plant performance. Many of the lessons learned in other areas of the mine were utilised to design the truck level. This paper chronicles the benchmarking, equipment selection and design of the level. Areas covered will include haulage trucks, level layout, ore chute design, traffic control, road design and crusher layout.

Jan 1, 2000

By Jimbo I, Ogawa O

A series of experiments was carried out to investigate the solubilities of copper, arsenic, antimony and bismuth in silica-saturated iron silicate slags under controlled oxygen partial pressures at 1200 and 1250¦C. Molten copper containing each of the above elements was kept in contact with a slag in a silica crucible for 24 or 48 hours to attain equilibrium. No me- chanical entrapment of metal into the slag was observed. The appearance of the magnetite phase in the slag was avoided by holding oxygen potentials at substantially lower values than that evaluated from available data on iron silicate slags. Solubilities of copper, arsenic, antimony and bismuth in slags were plotted against oxy- gen potentials and both oxidic and atomic types of dissolution were found, except in the case of arsenic, from the dependencies of the solubili- ties on the oxygen potential and from positive intercepts of regression lines when extra- polated to zero oxygen potential. The dissolu- tion of arsenic seemed mostly oxidic. Distri- bution coefficients of arseò,ic, antimony and bismuth between copper and slag are also Discussed.

Jan 1, 1980

By J du Plessis, W Marx

The FutureMine Collaborative Research Initiative has been successfully completed after three years of activity. The main objective of this initiative was to provide applications of research previously undertaken in the DeepMine initiative in terms of realistic solutions to problems facing gold mining operations as they reach for depths beyond 3500 m below surface. The FutureMine initiative was subdivided into four broad streams of technological expertise: rock engineering and seismicity; mining engineering and orebody management; software and communications and ventilation, cooling and refrigeration. This paper presents a summary of research output in this last area of expertise. Broadly, research in mine ventilation, cooling and refrigeration was directed in areas related to the recirculation of air, cyclical use of ventilation and cooling systems, air scrubbing technology, optimisation of chilled water reticulation, obtaining direct cooling at the workface, improving underground refrigeration systems through dry air-cooling and water heat rejection systems and a number of software simulation programs to be used in specific applications and as a tool assisting real-time monitoring of underground environmental conditions.This paper describes in broad terms the outcomes from this section of the research program and proposes ways in which some of these technologies may be combined synergistically in novel systems aimed at maintaining acceptable environmental conditions while reducing the impact on the profitability of operations.

Jan 1, 2005

By Fengyan D

Removing the interference of latter events, the data of geophysical (such as gravity and aeromagnetic) anomalies may indicate whether the mobile belt exist and whether the adjacent terrains of the mobile belt originally belong to one single unit. The petrotectonic assemblage can provide informations about the tectonic setting where it was generated from. The structural style can exhibit the kinetic and kinematic processes. The form of ancient isogeotherm may reflect the ancient geothermal regime which is related to the tectonic mechanism. In general, the early Precambrian terrains suffered polymetamorphism and multiple structural deformation. The researches must be carried out for the distribution of paleogeotharm and m.tamo'phic facies and zones on the basis of recovering the early structural style with structural analysis method; then a relatively correct conclusion may be geined on the ancient geothermal regime. This method can be known as "Ancient Thermotectonic Analysis". Through the sythetical research, a real knowlege about the tectonic setting of early Precambrian mobile belt can be obtained.

Jan 1, 1990

By Qisu W

The ground vibration produced by the bench blasts of a single hole and a row of two or three holes is recorded in an iron mine. Using the seismic signal generated by a single-hole shot as the source function, we have developed a computer program of a simulating ground vibration by bench blast. The reasonable delay time of blast in the iron mine has been discussed tentatively with the Fourmap invented by Anderson, D.A. The seismograms measured from the single-row blasts of two or three holes have shown the method of simulating vibration is feasible on the whole. For large scale production blasts, a combination of the vibration simulation and the high-speed photograph is used to choose the delay Time.

Jan 1, 1990

Valuers will often intuitively express the probability that property value will exceed a certain amount . . . 'I think the chances that the value will exceed $50 million are excellent. The chances that they will exceed $80 million are poor'. This paper shows how it is possible to combine the uncertainties of the value of several key items to provide an estimate of the probability of a certain overall value being achieved. The valuation of a large copper/gold deposit was naturally influenced by uncertainties in the base assumptions of costs and metal prices. Potential acquisition of the property through share purchase raised the issue of what was a reasonable intrinsic value for the shares. Market considerations could be used to appropriately adjust the intrinsic value. After a range of possible metal prices and operating costs were determined, estimates were made of their probable distributions. By combining these probabilities in a random selection, a range of property values was calculated. Each value had its respective probability of occurrence. This allowed a most likely value of shares to be calculated. This paper demonstrates how the valuer's intuition is complemented by numerical analysis.

Jan 1, 1994

By Swift D. G

For some time the Electricity Trust of South Australia (ETSA) has been investigating the application of new mining methods and equipment to minimise the cost impact of the steadily increasing depth of mining brought about by the 20¦ dip of the coal seams at the Leigh Creek Coalfield. Exhaustive examination of all suitable mining systems showed that highly mechanised systems involving belt conveyors displayed no eco- nomic or operational advantages over shovel and truck methods. However, the configuration of the Leigh Creek coalfield allows for two quite different approaches to mining by shovel and truck. The current strip mining method involves removing overburden from the highwall in 60 m to 200 m wide strips to progressively expose the coal down dip, and requires all waste to be hauled to the surface. The alternative ter- race haulback method involves opening a boxcut to full depth at one end of the coalfield, then mining the full section along strike and placing the spoil in the mined out area. On a strictly economic basis, the latter is clearly advantageous, but the former has significant less tangible advantages. In deciding between the two methods ETSA is faced with the need to examine the applicability of each method under a wide range of possible future demands on the coalfield, and to assess the importance of many intangible factors.

Jan 1, 1989

By Morris P. H

A trial embankment was constructed using coarse coal mine reject on a deposit of crusted coal mine tailings at New Hope Colliery, located in the Bundamba District of the West Moreton Coalfields in South East Queensland, Australia. The purpose of the trial embankment was to assess the load carrying capacity and settlement behaviour of the crusted tailings, including an assessment of strength gain in the tailings under the influence of the fill. Prior to construction of the trial embankment, a site investigation of the tailings deposit was carried out. This comprised vane shear strength testing, together with disturbed sampling and undisturbed block sampling for the purposes of laboratory testing. Following the site investigation, settlement plates and standpipes were installed at various depths and locations within the tailings in the vicinity of the proposed embankment. The instrumentation enabled the magnitudes and distributions of settlement and pore pressure within the tailings to be determined during and following construction of the embankment. The embankment was constructed using coarse reject in three equal lifts to a height of 3.0 m. The tailings sustained a maximum settlement under the weight of the fill of 290 mm, representing about 4.2 ii of the average initial thickness of the tailings and a loss of embankment height of about 9.7 %. By the end of the monitoring period the strength of the softer tailings underlying therust had roughly doubled under the influence of tha cmbarikment

Jan 1, 1990

By Peirong C, Pei N, Shouxi H, Hongzhong X

Indosinian (T) orogeny amalgamated the Mongolia-Xingan fold zone, the North China continent, the Yangtzi platform and the SE China fold zone into a unified continent. The early to middle Yanshanian (J-K,) orogeny created a Cordilleran type active continental margin in East Asia, reactivated the consolidated East China continent, and generated a large amount of granitoids, calc-alkaline volcanics and W, Sn, Mo, Cu, Au, and U ore deposits. The late Yanshanian (K2) orogeny began a transition to the western Pacific type continental margin. A tensional environment led to the development of peralkaline magmatism and the formation of continental basins with red beds. The Himalayan (Tr-Q) orogeny was characterised by a backarc spreading and rifting regime. The dominant magmatism was continental basaltic.

Jan 1, 1995

By Polthier K

A short discussion of the salient aspects of a dispersed flow model in relation to the gas flow in blast furnaces is given. The use of the theory in assessing vessel performance is mentioned. Tracer results of a blast furnace (688 m3) from three furnace levels and different radial positions are analysed and results presented as D/ud values. The significance of the shapes of experimental tracer curves are included and comparison is made with results obtained on other furnaces.

Jan 1, 1975

By Fullagar P. K

In resource definition and mine development, major capital expenditures are committed on the basis of sparse information and even in production surprises such as bad ground are not uncommon. Drill holes constitute the principal source of information about the orebody and its environment and optimisation of drilling implies maximising the yield of useful information per dollar expended. Geophysical borehole logging provides new flexibility for optimising the drilling budget. Economic benefits can flow from geophysical logging at all stages of the mining cycle. The most commonly cited benefit is substitution of diamond delineation drilling with cheaper percussion or reverse circulation drilling in cases where geophysical logs can substitute for core. This approach can deliver an attractive direct saving in drilling costs (and time) if drill meterage is unchanged, or a potentially greater indirect benefit from better ore control if more holes are drilled within the original drilling budget. More ore contact intercepts per dollar can translate into lower dilution and enhanced ore recovery, thereby increasing revenue as well as reducing mining costs. Substitution of diamond drilling with percussion drilling is not always feasible. However, geophysical logging of diamond holes is often highly advantageous in its own right, both for geotechnical characterisation as well as ore delineation. Operational advantages of logging include data objectivity, speed of interpretation and reduced core handling and analysis costs. Geophysical logging assists mining engineers by providing a continuous measure of in situ rock strength, even over intervals with poor core recovery. The additional expense of geophysical logging in blast holes can be justified in terms of more accurate ore boundary delineation and rock strength evaluation. Precise ore boundary delineation permits refinement of charge placement, to minimise dilution and maximise recovery. Detailed knowledge of rock strength can enable optimisation of blast design. Rock strength can be evaluated in real-time via analysis of drill performance data recorded with measurement-while-drilling (MWD) technology. To successfully apply geophysical logging in mines, its technical, operational and economic viability must all be established. This entails verification of the existence of appropriate physical property contrasts, investigation of the best way to integrate the geophysical results with the mining method and an objective assessment of the value of the resulting mine performance benefit. Geophysical logging is already well established in many mining operations. The greatest impediments to its wider utilisation at mines are: lack of appreciation of geophysics by most mine geologists, engineers and managers; limited interpretational aids; and the necessity to re-enter completed drill holes. In this paper we endeavour to address these issues by informing mine geologists about potential applications of geophysics, by illustrating automated interpretation of geophysical logs and by highlighting the importance of emerging MWD and logging- while-drilling (LWD) technology.

Jan 1, 1997

The economically significant seams in the Bowen Basin fall into four age groups, two in the Lower Permian and two in the Upper Permian. Coal deposition in the Galilee Basin did not commence until late in the Lower Per- mi-an and persisted into the Upper Permian. The Lower Permian and early Upper Permian coalfields of the Reids Dome Beds, the Collinsville Coal Measures and the Fair Hill-German Creek Formation are restricted to the west flank of the Bowen Basin. The uppermost Permian Rangal-Elphinstone-Baralaba Coal Measures have widespread distribution across the northern half and on both flanks of the Basin. Coal Measures in the subsidiary basins at BlairAtho/ and Ca/en were probably deposited at the same time as the Collinsville Coal Measures. The structure of the north west flank of the Bowen and the east flank of the Galilee Basin is essentially simple, but in the remainder of the basin doming and faulting complicate the structure. Also, bordering a large sec- tion of the east flank, is the Dawson Tectonic Zone, where the beds are tightly folded and faulting is intense. Cok- ing of seams is common in the northern sector of the Basin associated with igneous intrusion. With the exception of the Duaringa Basin on the east flank of the Bowen Basin, Tertiary sediments and basalt flows are more common at the western basin margin. Thick deposits of Tertiary sediments also occur in the south of the Galilee Basin. Con- sequently, coal subcrop, especially in the older, more westerly situated, coal measures is often at depths in excess of 100 m. East of this, the depth of weathering can be as shallow as 13 m and most of the coal subcrop is acces- sible to mining by open cut techniques. Coals deposited in the early Upper Permian are commonly more vitrain rich than those above and below. In the Bowen Basin, coal rank decreases from the north west to the south east, that is, from the semi-anthracites associated with the Dawson Tectonic Zone to the sub-bituminous coals of the southern Galilee Basin.

Jan 1, 1975

By E Ben-Dor, D Bakun-Mazor, Y Ben-Ari

Determining the mechanical properties of rocks is important for various civil engineering fields, including the mining of raw materials for aggregates used in the construction and paving industries. Traditionally, the mechanical properties of rocks are obtained through in situ and laboratory tests during geotechnical surveys. However, these time-consuming surveys involve many resources. In contrast, hyperspectral remote sensing methods make it possible to identify the mineralogical composition and crystallographic structure of the rock; properties that control the mechanical properties of the rocks. In this work, we characterise the mechanical properties of carbonate rocks by using a hyperspectral sensor in laboratory conditions. We collected about 150 cylindrical samples of carbonate rock, with a wide range of strength values from several rock outcrops in Israel. We used a point spectrometer in the range of 0.4–2.5 μm and a spectral image sensor in the range of 3.0–12.0 μm, scanning the samples to obtain the signature of their light reflections and spectral emissivity. We then measured the samples’ density, porosity, water absorption, and uniaxial compressive strength (UCS). We used sophisticated data mining to find statistical relationships between the hyperspectral signatures of the samples and their mechanical properties. We used this data to identify the most dominant wavelengths for predicting mechanical properties. We found that the density, porosity, and water absorption of carbonate rocks could be confidently predicted based on spectroscopy data, while the UCS of the rock could also be predicted, but less significantly. The results of the study pave the way for the development of measuring tools for the mechanical properties of rock, based on non-destructive tests of quarrying materials.

Nov 29, 2022

The (SA Mine at Cobar produces a mix of copper and copper lead and zinc ores fran long hole open stopes. Primary jaw crusher product is fed to two parallel primary autogenous mills followed by a secondary ball mill. Each mill operates in closed circuit with cyclones. Grinding equipment and the main operating variables are described. Copper lead and zinc flotation concentrates are produced sequentially. The control systems and operating strategies are described.

Jan 1, 1983

The treatment of steels with acid solutions for the removal of oxide products represents possibly the largest outlet for chemicals in steel processing. Organic pickling inhibitors are required to prevent base metal attack by these acids otherwis

Jan 1, 1980

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

Coal water mixture (CWM) is a mix of finely ground coal with water and a small amount of chemicals. It is a new way of transporting and handling coal. CWM can be transported, stored and burned like fuel oil in steam generating boilers. It also has some environmental advantages over both oil and bulk coal. A group comprising Ube Industries Limited, Nissho Iwai Corporation (both from Japan) and Coal & Allied Industries Limited has been working in Japan and Australia since 1987 on a joint feasibility study into the production, transport and marketing of CWM from Australia to Japan. The group has been studying the development of a large-scale CWM plant on Kooragang Island at the mouth of the Hunter River at Newcastle, NSW. The project concepts and engineering plans for the CWM plant are well advanced and other studies related to the project are continuing.

Jan 1, 1995

By Pollard D, Meadows N

The presence of impurities which are electropositive to zinc in acid zinc electrolyte causes changes to deposit morphology and reduced current efficiency. Glue may be added to control some impurity effects, but assaying for animal glue concentration is difficult and seldom done. Measurement of the activation overpotential for zinc deposition by cyclic voltammetry is used in some plants to monitor electrolyte quality and control glue additions.The deposit morphology and current efficiency of zinc deposition from commercial electrolyte were investigated for various glue additions in the presence of increased levels of antimony. Cyclic voltammetry was investigated as a method of optimising glue additions in the presence of antimony.Scanning electron rnicroscopy showed deposits characteristic of the impurity element present and the glue addition rate. Cyclic voltarnmetry measurements showed some correlation between current efficiency and activation polarisation potential. The importance of using tankhouse electrolytes where results are to be related to tankhouse operation was noted.

Jan 1, 1988

The rapid growth of world civilisation will have a significant impact on the way humans live in the future. As the global population increases and more countries demand a higher standard of living, the world must provide more food and greater energy and mineral resources to sustain this growth. The difficulty of doing this is compounded by three broad trends: the conversion of agricultural land to development uses; the increasing urbanisation of the world's population; and growing concern for the maintenance and improvement of the environment, especially regarding global warming and the impact of population growth. Underground space utilisation offers opportunities for helping address these trends.

Jan 1, 1993