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SINCE 1900, five underground fires of consequence have beenrecorded in the Broken Hill mines. These occurred at the Junction(1906), Proprietary (1906 and 1916), Block 14 (1906), and Centralmines (1923). All have been extinguished, but at an enormouscost; e.g., in the eleven months following on the 1923 Central mine fire the sum of £187,123 was expended in fire-fighting operations.To this series may be added others, as the South (1925) and British mine (1918) fires, which were extinguished before serious damage had resulted. All, however, have occurred within a period of 28 years, and in a district where spontaneous combustion, a prolific source of fire in the U.S.A., has been practically nonexistent. Therefore, definite fire risks exist in the underground workings of the Broken Hill mines, and, as a consequence, an active fire prevention policy is a necessity...

Jan 1, 1929

By Shrivastava P

The iron orebodies of the Pilbara region are formed by supergene enrichment of banded iron formation and rarely do such processes produce orebodies with uniform grade distrib- utions. The orebodies being mined or developed have to be worked to grade/quality constraints imposed by contractual agreement rather than natural characteristics. Hence it is imperative to use a non-biased ore reserve calculation method. The geostatistical study of a typical iron orebody is presented. Emphasised are the geological characteristics of the orebody manifested as a variable grade distribution of iron and impurities; the determination of variogram model; subsequent uses of the model for computation of ore reserves and kriged lock estimates; computation of dispersion variance and conditional simulation of orebody.

Jan 1, 1977

The major greenhouse gas emissions from coal combustion are leading certain people to argue for uranium mining and nuclear power to meet these challenges. Although there is considerable rhetoric around promoting nuclear power as 'green' due to its relatively lower greenhouse intensity, a careful study of the data is required to properly underst and the sustainability of uranium mining and nuclear power and whether it can or should have a role in future energy supply scenarios. This paper presents detailed research and analysis on uranium mining, focusing on known economic resources, production, solid waste and water management, pollution issues as well as energy and greenhouse aspects. A particular focus will be on Australia and its operating and prospective uranium mines. Overall, the paper raises fundamental issues concerning the long-term sustainability of uranium mining and nuclear power and documents the greenhouse intensity of uranium production and the nuclear fuel chain.

Jun 1, 2010

By Cousens DR, Benhamou M, French DH

Techniques appropriate to petrographic image analysis are being developed using digitized backscatter electron images of well characterized mineral assemblages obtained from a Cameca scanning electron microprobe. Emphasis is on developing descriptors for size, shape and association of mineral grains as these all convey important information concerning the nature of rocks and the processes that have operated upon them. Processes, for example, that could indicate the proximity of mineralization. For convenience, the work is being carried out on the PDP11/73 host computer of the electron micropt be, although it is recongnized that such a multi-user environment is not appropriate for practical image analysis. The eventual aim is to develop a low-cost microcomputer-based package for quantitative description of mineral textures and rock fabrics as an objective aid to the petrographic analysis of ores and host rocks.

Jan 1, 1989

The physical phenomena which influence gas flow in the bosh and hearth of a blast furnace are discussed including the hold-up of slag as a mechanism which can result in a flooding condition. An equation is defined which describes the limitation to wind volume arising from the flooding condition. Implications of the various factors influencing bosh and hearth gas flow on furnace operation are discussed. Coke quality is shown to be the most important factor in the aerodynamics of these zones and coke requirements are defined for the Port Kembla No. 5 BF which has an inner volume of 2670 m3.

Jan 1, 1975

Over the past seven years, a combination of New Zealand-, Australian- and German-led research voyages using the research vessels Tangaroa, Southern Surveyor, and Sonne respectively, have revolutionised our understanding of the Kermadec-Tonga arc-backarc systems. This convergent margin is the most seismically-active subduction zone system on Earth with convergence rates steadily increasing northwards from the Hikurangi Trench to ~250 mm/year at northern Tonga. In combination with the intra-oceanic setting, factors potentially producing magmatic, tectonic, and hydrothermal variability in this system include an increase in potentially subductable sediment northwards along-strike, intersection of the Louisville Ridge (hot-spot chain) and Osbourn Trough (paleo-spreading centre) with the arc at ~25¦S, and the possibility of Samoan (hot-spot) plume ingression in the northern Lau Basin. The bulk of the magmatism is submarine; whereas only a few emergent (some transient) volcanic islands exist, about 80 submarine volcanic centres of significant size (>1000 m above surrounding sea floor) are present between White Island in the south to north of Tafahi in Tonga. About 35 per cent of these centres are hydrothermally active. Important petrogenetic features of the volcanic rocks along this arc system are the abundance of rhyolite (some quartz-amphibole-bearing), and the outcrop of primitive olivine-clinopyroxene-phyric basalts in satellite cones of the major edifices. Many of the edifices consist of complex caldera systems. Eruptions from and degradation of these edifices were probably tsunamigenic. Many of the hydrothermal systems developed within the edifices are likely destroyed during the sector collapses which are the characteristic edifice degradation mode. There are three backarc spreading systems along this margin: the Havre Trough, Valu Fa-Eastern Lau Spreading Centre, and the nascent Fonualei Rifts. The latter are particularly notable in having captured the entire suprasubduction zone magmatic flux for a distance of about 150 km, shutting down the adjacent volcanic front arc volcanoes.

Jan 1, 2005

An understanding of the importance of the different components that comprise a rock bolt unit is necessary to ensure the proper use of rock bolts as a means of roof support. The various anchors, bolts and plates in use in Australia have been designed and adapted for Australian con- ditions. As mining conditions change, so will the types of bolts in use. This is apparent in the development of chemical anchors and other recent innovations.

Jan 1, 1971

Leichhardt Colliery is developed for underground mining of coal seams at depths exceeding 280 m. Investigations of the area were conducted in phases, each designed to delineate seam characteristics more accurately and to indicate with increasing precision the nature of local geological features and the ranges of those coal properties susceptible to variation. The investigational campaign is described phase by phase summarizing evaluation of the area at the conclusion of each phase. Predictions of geological conditions likely to influence engineering planning are contrasted with actual conditions observed during trial mining.

Jan 1, 1974

By L Whitbourn, K Yang, P C, E Ramanaidou

The potential of hyperspectral mineral mapping within a mine environment is demonstrated. Central to this capability has been the development of portable or vehicle-mounted, hyperspectral mine face-mapping systems. Data from these systems were used to detect subtle mineralogical variations and map their distribution across rock faces in a fashion that previously was not possible. In one study, the data usability was enhanced by ædrapingÆ the mineralogical determinations over a three-dimensional æmodelÆ of the rock-face. The eventual melding of the spectral mine face-mapping and three-dimensional spatial technologies will result in a new generation of mineralogical and structural information becoming available to mine geologists, engineers and metallurgists. Specific uses for spectrally-derived, mineral mapping data sets could include:ore grade mapping systems based on either direct detection of ore minerals themselves (eg iron and nickel oxides), or mineralogies that may be used as surrogates for ore-grade information (via various alteration minerals) after a suitable orientation survey; detecting mineralogies that have a deleterious effect on milling, metallurgical processing or have occupational health implications (talc, swelling clays, carbonates, asbestos, etc); selective mining and blending by collecting, processing and displaying such mineralogical images in near real-time to monitor ore grade and quality, and allow the separation of ore from waste during loading operations at the mine face; a mineral detection and mapping capability to assist in structural and geotechnical mine planning applications; and an enhanced geological detection and mapping capability for ore mineral species or alteration mineralogies that may be used to vector further mineralisation, update the existing mine ore model, or provide input to assist in the control of autonomous mining equipment. Within the Woodlawn open pit, Fe- and Mg-chlorites and phengitic- micas associated with sulfide mineralisation were detected and mapped. Subsequent studies using a second generation face-mapping system demonstrated the direct detection of ore-grade materials for iron-ore and nickel laterite mining activities. Satisfactory and meaningful results were extracted from data that were collected under a variety of challenging conditions. However, these non-ideal climatic and operational conditions would be expected under most operational situations in a mine environment. Development of a system using artificial illumination, permitting night-time (and eventually underground) operation and elimination of atmospheric absorption effects is underway.

Jan 1, 2006

The extraction of the values from gold bearing clay or clayey ores has always presented difficulties. A description of the successful operation of a mill working on material of this nature is here given in the hope that it will be of interest to mining engineers and metallurgists, particularly as the ore body referred to has been worked out. The methods finally adopted were evolved at the mill after the failure of 3: plant specially designed in England and sent out to New Guinea to cope with the clay by the old principle of calcining to brick followed by crushing and cyanidation. A description is given of the direct cyanidation of run of mine ore in '90 ton vats; which was finally adopted after a great deal of study and experiment. Mention is also made of the method of removing overburden in the open cut and the mining and transport of the ore from the open cut to the mill. The purpose of the paper is to record these matters while the information is still available. . .DESCRIPTION OF THE ORE BODYThe values occurred in a flat-lying lode which had slipped about half a mile down the mountain side and had come to rest in the nearly horizontal position in which it was found and worked. The thickness of the deposit varied from a maximum of about 25 ft. at the northern end to about 10 ft. at the southern end. The ore body was capped with an overburden of decomposed breccia and porphyry of variable thickness the maximum being about 65 ft. The underlying rock, or the footwaIJ of .the flat ore body was breccia locallyknown as blue breccia.

Jan 1, 1951

By Cripps-Clark CJ, Deague TK

In order to study conditions under which SiO(g) may be formed in a blast furnace, equilibrium phase diagrams were constructed for the combustion of high and low ash cokes with oxygen-enriched blast and oil injection under conditions of high and low raceway pressures. Free energy minimisation techniques were used to calculate the composition of gaseous and condensed phases. Where coke ash is assumed, for simplicity, to comprise Si02 only, the coke can be comple- tely gasified, mainly to SiO and CO, under restricted conditions of coke to blast ratio and at temperatures greater than 1600 - 1650¦C, depending on system pressure. The formation of SiO(g) is partially suppressed by the introduction of alumina into the ash, because of the formation of solid and liquid alumino- silicate compounds. The minimum temperature for complete silicon gasification is raised to about 1700¦C. The results of the equilibrium calcula- tions are related-to actual raceway conditions. It is proposed that virtually all silicon in the coke ash is gasified such that, on condensation, it affects hot metal chemistry and slag properties and secondly, that the effects will be greater with higher ash cokes.

Jan 1, 1980

By Muir D. M

Highly saline process water has a number of implications for the CIP process during the leaching, adsorption and recovery of gold. The reduced oxygen solubility in saline water can seriously reduce the rate of gold leaching, while dissolved oxygen meters do not necessarily reveal actual oxygen concentrations in saline water. High levels of magnesium in the ground water necessitate operation at lower pH (-9), with the potential for greater cyanide loss via HCN stripping. In addition increasing salinity renders viscosity modifiers largely ineffective.The adsorption capacity of aurocyanide onto activated carbon is improved with increasing salinity, but misleading results can be obtained in assessment of gold loading kinetics of plant carbon samples already loaded, or partially loaded, in saline water if subsequently tested in fresh water. Elevated chloride levels in the Zadra elution process can cause severe anode corrosion in the elecuowinning cell. The Anglo elution process is tolerant to only slight increases in water salinity, but elution times can be reduced by ethanol addition. Care is required in carbon regeneration, as salts can catalyse carbon decomposition as well as increase kiln corrosion.

Jan 1, 1994

The state-owned Swedish company LKAB is one of the world's largest producers of iron ore. LKAB mines the greater part of its ore underground, and very high efficiency is vital if it is to compete successfully with open pit mines. Consequently, computers and OR are essential parts of the company's operations. This paper gives some examples of success- ful computer and OR applications at LKAB, coupled with some remarks on the costs and benefits of OR.

Jan 1, 1977

By Eri G

Ok ledi Mining Limited underwent a major transition from radio based truck dispatching to computerized dispatching for its equip- ment fleet in October, 1996. Modular Mining's Computerized Dispatch System was selected based on reputation and superior customer support. Modular's dispatch system is a fleet management system that uses computer, data communication and global positioning sys- tem technology to produce automatic, optimized haul truck as- signments. Optimization is achieved by equally distributing trucks to shovels so that truck queuing and shovel idling times are mini- mized. Computer illiterate mine operations personnel had to overcome a rather steep learning curve to use the high technology equipment. fortunately the system was able to be configured to use bitmap

Jan 1, 1997

Nickel WestÆs Kalgoorlie Nickel Smelter operates three Peirce-Smith converters, each processing 110 tonnes of matte per charge. The vessels are lined with chrome-magnesia refractory with a mouth traditionally constructed from steel liner plates, protected with cast refractory. Mouth refractory is damaged by molten material and the action of cleaning solid buildup off the mouth. Once damage has accumulated, the mouth must be frequently maintained with hot refractory gunning or a mouth leak may occur. Such a leak requires a 32 hour repair period. A converter mouth redesign program was undertaken with the aim of reducing the rate of mouth damage during operation, eliminating mouth leaks and shortening mouth replacement times during vessel rebuild periods. An overview of the redesign process and operational performance is contained herein.

Jan 1, 2005

This paper discusses design concepts in planning a large modern bulk terminal. The need is emphasised for a studied master plan, in-built materials handling flexibility and staged development. An integrated approach is advocated, combining functional purpose designed foundations and structures to serve their mechanical, electrical and environmental functions. Dry bulk and slurry handling are also compared in perspective.

Jan 1, 1983

The ownership, policies, organisation, structure, market, financial considerations and communications of a large resource project vary significantly through its discovery, feasibility, development and production phases. The extent of these changes, from discovery in 1957 through to 1979, is examined for the Mt. Newman iron ore project in the Pilbara region of Western Australia and some of the factors that influenced it are detailed. This shows that only some of the influences are under the control of the mine owner/operator, despite their significant impact on the returns for the massive capital invested. The effect of the general business climate on the various phases is also examined.

Jan 1, 1980

By Longworth C. R

This paper descrioes a case history of a coal mine which developed un'tahle roof conditions due to mass sliding of the overburden strata on a claystone band within the coal seam. The sliding is believed to have been initiated by stress relief associated with the removal of overburden alongside the entry portal of the underground workings. Once in motion, the roof block was kept moving by bulking due to roof collapse in the normal underground goafing operations. Control measures in the form of an earth and rockfill buttress against the entry portal and a sequential mining plan to create goaf areas alongside the entry portal have been initiated to attempt to limit movement. The operation has been continually monitored and a gradually decreasing pattern of movement is being re, orded.

Jan 1, 1981

Good morning. I am very pleased to be invited to present the Opening Address to this inaugural New Zealand Minerals & Mining Conference. It is indeed a pleasure to see so many representatives of this industry, which is so important to New Zealand's economy, present here today.   I extend a warm welcome to all delegates, particularly those from outside New Zealand. To those of you who have travelled from offshore, please closely observe our industry, and do not hesitate to ask Crown Minerals staff here for any further information you may want. I trust you will soon come to the same conclusion that my two following speakers have; that New Zealand is a good investment destination, and further that many of you will decide to invest in New Zealand's minerals and mining industry.   In New Zealand the minerals industry - minerals, coal and petroleum - together constitute an approximate $2.5 billion per year business. In broad terms this is about 3% of our Gross Domestic Product.

Jan 1, 1997

By Jackson S

An investigation into different aspects of importance in the understanding of explosibility of hybrid mixtures of coal dust, air and gases potentially found within mine workings through a comprehensive laboratory program of explosibility tests was conducted. Plotting of test results revealed that conditions of potential explosibility could be described using two dimensional flammability limit surfaces- for coal dust/oxygen; methane/oxygen; and coal dust/methane mixtures. From these plots, the three dimensional flammability envelopes defining the explosibility of the coal dust/methane/oxygen mixtures can be defined and illustrated for a coal sample. The surfaces of the three dimensional envelope describe limits which separate inert mixtures of coal dust and methane at varying oxygen levels from those concentrations which are ignitable under defined conditions. It is considered appropriate to generalise that the geometric shapes of these limit regions are applicable to all type classifications of coal dust. There are practical applications of these results to the underground environment.The action of free radical initiators in the propagation of a methane gas explosion was examined for its applicability to the flammability of coal dust/gas/air mixtures. The oxides of nitrogen or NO x radicals have influence upon the lean limits of flammability of hybrid mixtures and this is illustrated by use of three dimensional coordinate geometry. Gases can be introduced to the underground environment through the exhaust gases of diesel equipment. It is concluded that radical species can substantially increase the flammability of gas and dust flames and as a consequence raise risk of mine atmosphere explosibility.

Jan 1, 1998