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By R Hindstr÷m

The demand for iron ore has increased dramatically in the last years and is forecast to remain on a stable high production level for years to come. ItÆs expected that the world economy is facing a stable continuous growth of iron ore to two billion tonnes and more over the next decades (Beddows, 2007). Furthermore it is expected that the existing and known high-grade ore resources will decline, and the iron ore industry will be forced to implement more and more advanced beneficiation plants. As a consequence of the more complex beneficiation requirements, there will be a need for modern solutions for iron ore dewatering that are reliable mechanically as well as cost effective and with high capacity per unit at the same time. Conventional vacuum filtration methods have been the most prevalent in fine iron ore dewatering. Product quality needs, lower ore grades, complex mineralogy and energy costs have resulted in iron ore producers seeking better solutions for dewatering, in particular pelletising feed. New advanced filtration methods have been introduced to the market. This paper describes how these modern methods are answering the needs of the industry. Performance of advanced dewatering technologies (pressure filtration and ceramic capillary action filtration) for iron ore applications has been studied, and the findings are based on both industrial and pilot scale experiences on different materials. For example, the results show that the cake moisture content of iron ore pelletising feed can be optimised more effectively by using modern filtration technologies. By selecting the most suitable and adjustable equipment, the effects of variations of feed material on downstream processes can be minimised and the possibilities of processing more difficult raw materials to high-quality pellets are better. The Larox Corporation develops, designs and manufactures industrial filters and is a leading technology company in its field. Larox is a full service solution provider in filtration for separating solids from liquids. As such, this paper compares the new developments in this market area with the prevailing known vacuum filtration technology, but focuses on a comparison between capillary action filters and rotary vacuum disc filters (RVDF). The trade name CeramecG is used to differentiate the Larox filter from the generic term.

Jan 1, 2007

THE Company's smelting equipment consists of three blast furnaces, supplied with blast from two sets of vertical piston blowers, each capable of delivering 8000 cub. ft. of air per minute at a pressure of 60 oz. per sq. in. Each blower is belt-driven by a 1:30 h.p. motor. The maximum speed of the blowing engine is 35 r.p.m.No. 1, the largest of the three blast furnaces, has a crucible area of 49.5 sq. ft., and measures 11 ft. 6 in. x 5 ft. at the tuyeres.From tapping floor to feed floor measures 35 ft. 9 in., and holds, when full, 100 tons of charge. Blast enters through thirteen 3-m. tuyeres at 60-oz. pressure. Working normally, this furnace is capable of treating :300 tons of charge, exclusive of returned slag and coke, per 24: hours, with an output of 100 tons of lead. Tapped slag flows into a C.l. forehearth mounted on wheels, where any lead and matte is caught, and the slag overflows into a 3-ton cast-iron pot, in which it is drawn away by an electric locomotive and poured over the dump.

Jan 1, 1918

By Mann T

The use of dolomite as a refractory began in England about 1870 when the basic Bessemer process for the removal of phosphorus from steel was developed by Thomas and Gilchrist.Knowledge of dolomite as a refractory in this country goes back to the early part of this century, at the time when the Hoskins Brothers took over the Lithgow Iron and Steel Works from W. Sandford. The practice then was toimport burned dolomite in casks from England. It is reported that much of the material was powdered when received, but was still serviceable. The earliest. used sources of local stone were in the Bathurst and Mudgee areas of New South Wales, and these dolomites were first used raw. Later, dolomite was burned in cupolas at Havilah near Mudgee, coke being obtained from the South Coast of New South Wales. This plant supplied burned dolomite to the Lithgow steel plant, later to the Australil1n Iron and Steel plant at Port Kembla, and also to the electric steel furnaces at Newcastle, Sydney and Melbourne until the plant was closed down in 1946.The Broken Hill Proprietary Company first obtained its dolomite from George's Plains near Bathurst (this was, really a magnesium limestone) and later from Mount Knowles, a deposit near Mudgee, which was eventually taken over by the CO:plpany in 1918. In 1936 Australian.Iron and Steel acquired from the Southern Portland Cement Company a deposit at Mount Fairy in the Federal...

Jan 1, 1951

The paper discusses the characteristics of Be-zymianny activity during the last 2500 years. Three periods of increased activity have been identified which are the eruptive cycles lasting for 100-400 yrs. The periods of high activity fall on the fol-lowing time intervals: 2400-1700 yrs ago, 1350-1000 yrs ago and from 1955 ixp to the present time. The 1955-1956 catastrophic eruption after a long period of repose (about 900-1000 yrs) opened a new cycle of activity of the volcano which is continuing to-day. Several decades are distinguished in activity which differ in character and intensity of eruptions.

Jan 1, 1990

By Hughes DC

Coal development in New South Wales can involve a complex series of government approvals, a requirement that results from the coincidence of many development sites with environmentally sensitive areas. The concept of network analysis is applied to the pre- development regulatory procedures leading up to the grant of a coal lease. The network facilitates a quantitative and qualitative analysis of activity schedules relating to pre- requisite statutory approvals. The sequencing of activities (with clear start and finish nodes, identification of sensitivities and time estimates for completion of each phase of the network) provides government and industry with an effective planning tool.

Jan 1, 1983

By Fry P. R

Dragline operations have played a major and successful role in coal mining around the world for more than 30 years. Because of this long history, many of the operating draglines are reaching an age where maintenance and downtime costs are prohibitive, and decisions need to be made to either replace or refurbish them.In the current economic climate, refurbishment is a popular choice and this usually involves major structural repairs above and below the roller circle, together with replacement of the roller circle components. Often, the dragline tub is also replaced by a completely new one.

Jan 1, 1992

By Yongjin S

Datong coal Mine suffers from delays and sudden caving of its massive competent conglomerate roof. Detailed geological studies of the nature of pebbles and matrix of the conglomerate and its sparse bedding, joint and fracture structure, gave rise to investigation of water injection to destroy its strength and to control caving. Comparative investigations, including porisity, permeability, compressive strengths and water injection of conglomerate and sandstone led to empirical expressions relating various properties and to guidance for effective injection and caving practice. This new safe roof control practice should be even more improved with further research, including Modelling.

Jan 1, 1992

By Aziz NI, Beafi EY

In designing for a highly productive new mine during the present declining coal market, a very detailed ò planning is necessary. Attitudes of both management and coal operators may have to be changed, with more initial participation by the unions, governmental agencies, and the coal owners. A considerable number of Australian mines are remote from labour source and this trend is likely to increase particularly in the state of Queensland. Consequently such 'mines must be developed on the basis of the future technological and social changes in order to minimise both the capital and operating costs.

Jan 1, 1988

The unique characteristics of the Target orebody and modernistic approach to mining present significant challenges and a concomitant high potential for new opportunities. The break-away from the traditional labour intensive mining methods improves both safety and productivity significantly. The intention of the paper is to illustrate the application of well known mining methods to the particular requirements of a complex orebody at depth. The evolutionary process followed to establish the final mining method design provides insight behind the finished product, and the modern approach to the planning and service principles equips the reader with a suite of mining engineering ideas.

Jan 1, 2000

By Canterford JH, Ritcey GM

With the development of new technology and materials of construction, chloride-based hydrometallurgical routes have gained accept- ance as a viable alternative to sulphate-based routes. A number of commercial and pilot plants built and operated over the last decade have provided invaluable experience and con- fidence in their use. Chloride hydrometal- lurgy, with or without pyrometallurgical pre- treatment, is particularly attractive for pro- cessing complex Cu/Pb/Zn/Ag concentrates, nickel mattes and chalcopyrite concentrates. This review outlines recent developments, dis- cusses advantages, as well as indicating some of the problems still to be solved.

Jan 1, 1984

Underground mechanized excavation in New Zealand has become more commonplace in civil and mining applications during the last three years. At one stage up to seven Dosco Road- header machines were being used on different projects around the country. The Huntly West Mine Drifts inclined at one in four were by far the most severe grade conditions that the machines were subjected to; however, other operations posed their own particular problems for the machines. Two major interrelated factors became evident as soon as the machines commenced at Huntly. These were traction problems on the grade and control of water, particularly on the invert.

Jan 1, 1978

By Ellicott C, Webb N

In November 1996 the NSW Minister for Mineral Resources, Hon Bob Martin MP, commissioned ACiL Economics and Policy Pty Ltd to conduct a wide ranging review of safety within the New South Wales mining industry.The review was a response to a disturbing number of fatalities which had occurred in the industry during the Minister's term of office together with a number of alarming near misses where serious failures in mining systems had occurred. Shortly after the review was commissioned, four mine workers died at Gretley Colliery near Newcastle. An inquiry is currently being conducted into the incident.

Jan 1, 1998

By Ellis WK, Greenwood-Smith R

A nuclear technique for the analysis of copper in bulk materials has been developed and successfully field tested at Mount Isa Mines Limited. The technique utilises the gamma-ray resonance scattering process. A bulk analyser based on this technique gives a rapid and accurate measurement of the percentage by weight of copper or nickel aver- aged over a large mass of sample, typically 20 kg. The only sample preparation required for accurate analysis is crushing to -2.5 cm. At Mount Isa over 100 mineral samples covering a wide range of rock types and copper contents were analysed. Bulk analyser assays and chemical laboratory assays agreed closely for underground pillar-extraction and geolog- ical chip samples, conveyor belt samples, and finely ground samples from the ore concentrator. For the concentrator samples, the root mean square deviation between bulk analyser and chem- ical laboratory assays was 0.06 wt.% copper. The chemical assay errors for these samples were about 0.06 wt.%

Jan 1, 1975

The locality from where these specimens come is distant about 12 miles due south from the township of Bingara New South Wales, and is known locally as Carney's Reef, Barrack's Creek, Top Bingara. The formation traverses the western side of a serpentine spur from the main range, which runs through the country from the other side of Tamworth to Inverell, in the New England District. It has a due north and south trend, with an easterly underlay slightly out of the vertical. The formation has been opened up at different points for a distance of over two miles, and each place showing gold in the stone, and no place more than three to four chlins apart, the whole distance along the line of Reef being leased. The formation varies in thickness, the smallest being about 1 foot and the widest about 10 feet. The following is a list of properties, and description of work done on them at present. First south, and about one and a half miles from Hanion Brothers' old BalIarat claim due north, Court and patty hold a tenacre lease. The formation outcrops near the south boundary, and gold is obtainable in the stone. In the centre of the lease a costeen pit has cut the capping, which shows gold, and about two chains from the north boundary another one cuts the capping, also showing gold. The reef averages, where exposed on this property, 3 feet wide.

The basic make-up of the majority of currently produced bulk explosives has changed little in the last 20 years. These explosives would be described as mature in a life cycle analysis. Therefore these explosive products and the practical rules for their use are well understood and well established. In recent years there has been interest in low density explosives, predominantly due to ammonium nitrate shortages and the associated increase in the cost of explosives. In the use of low density explosives some of the practical rules for the more commonly used bulk explosives do not apply. Therefore a shift in the thinking among users is required. At a number of mines low density explosives have been trialled or are being used, utilising the practical rules that apply to bulk explosive products. This has led to poor blast results in many situations. These poor blast results have often then led to a reduction in the use of low density explosives at the mine. This reduction does not acknowledge the advantages that can be gained from this product in the area of reduced cost of mining. This paper looks at low density explosives and discusses how and why these products work. Included in the paper are some practical ideas and examples of how low density explosives can be effectively used at the mine site.

Jan 1, 2007

In most States of Australia it is a legislative requirement for underground mines to have a separate means of egress from the normal means of ingress to permit the safe evacuation of workers to the surface in event of an emergency. Such egress may be in the form of a ladderway equipped shaft/underlie or trafficable incline/decline. Additionally, there is a general requirement to have one or more airways, separate to the main shaft or other principal entrance of an underground mine, extending to the lowest level to permit ventilation to all parts of the mine. Fulfilling these requirement is difficult in the development phase of a mine when access underground is achievable by only a shaft or decline in the process by being sunk. What is frequently practiced in Australia is for production to then commence, sometimes in association with continuing development, in the same configuration without the establishment of this separate method of egress to the surface nor additional airway/s with reliance on refuge chambers to cater for back up in any emergency. Not only, could this jeopardise the health and safety of workers in case of an underground emergency it could be construed as a statutory breach of legislation. While recognising that refuge chambers are often used throughout underground operations nowadays their equipping and the criteria for their location needs to be bought into focus. This presentation discusses how such legislative requirement can be met alongside the use and appropriateness of refuge chambers.

Jan 1, 1998

By H Utama, R Heryadi

The demand for environmentally friendly commercial explosives has increased globally due to concerns regarding environmentally friendly mining activities. Ammonium nitrate fuel oil (ANFO) and bulk emulsion explosives (BEE) are two kinds of civil explosives primarily used in coal and mineral mining in Indonesia. Indonesia is one of the leading countries in coal and mineral mining production and export, with abundant resources; therefore, the consumption of civil explosives such as ANFO and BEE is enormous. The selection and evaluation of commercial explosives are mostly done on the commercial and technical side, and no assessment is made based on environmental aspects. This preliminary study evaluates the economic value and environmental burden of greenhouse gas emissions produced by ANFO and BEE and determines which type of explosives is more environmentally friendly. The combination of environmental and economic indicators, eco-efficiency (E/E), was selected to investigate BEE’s economic and environmental performance compared to ANFO. The life cycle of greenhouse gas emissions of BEE and AN was determined using previously available studies and simple calculations. The cost of the product or explosives was used to represent the economic value. The E/E results showed that environmental and economic sustainability could be enhanced using BEE.

Sep 1, 2024

By X S. Li

The modern mechanical excavation machines have enough power for cutting hard rock. The ‘bottle neck’ which limits the use of machines for hard rock excavation is ‘cutting tool’. To cut hard and abrasive rock, CSIRO has been developing Super Material Abrasive Resistant Tools (SMART*CUT). SMART*CUT technology replaces the tungsten carbide (WC) tip of conventional pick with thermally stable diamond composite (TSDC) and attaches the TSDC tip to steel tool body with CSIRO worldwide patented bonding technology. This paper introduces the key features of SMART*CUT, compares its performance with conventional WC tipped tools, discusses the challenges faced by SMART*CUT and the further developments needed for successful application of SMART*CUT to mining industries.

Nov 22, 2011

By R Yong, A McEwan, D G. Miljak, D Milinkovic, A Curtain, P J. Coghill, R Stefulj, B Lovric, G Roberts

The CSIRO has pioneered the development and use of certain classes of magnetic resonance (MR) for mining applications. The MR technique is a radio frequency-based spectroscopy that provides highly quantitative measurement of selected ore minerals. MR has many inherent advantages for bulk sensing in mining applications, including deep sensing penetration into most bulk ores with the use of non-contact sensors that are robust and tolerant of demanding mine conditions. The highly discriminating nature of the technique also provides the very desirable attribute of robust and simple calibration, that can often be performed prior to sensor installation. Rapid sensing (within seconds) at very low grade (few hundred ppm Cu) has been demonstrated, as well as sensing at high tonnage rate. Besides sorting applications, MR may also be applied to preconcentration applications involving very large volume sensing including: (i) haul truck sensing using portal arrangements, where truck destination assignment may be dynamically determined based on the truck grade, (ii) in-pit gantries used for loading trucks that may similarly be equipped with sensors for truck assignment and (iii) deep mine bench sensing, recently progressed through a CRC ORE project, where local bench grade is determined at the few-metre lateral scale and at depth prior to blasting, to aid selective blasting and ore extraction. MR sensor prototypes have been developed for each of these applications and have been tested in laboratory or limited field conditions. To inform the value proposition for truck or bench sensing, initial analysis of truck assignment improvement based on an analysis of in-situ mine bench grade has been performed for a porphyry style deposit. The prototype sensors, preliminary results and future technology development and objectives will be described.

Nov 10, 2020

By R Smart

This paper examines the longer-term predictive capacity of the GAMSPATH computer program (developed by the Alberta Research Council) for a waste rock (sample MS) obtained from the Kaltim Prima Coal (KPC) mine, Kalimantan that contained significant framboidal pyrite. The model was refined by comparison with the net acid generation (NAG) and column leach tests to provide a basis for calibration of the model for both short term and longer-term reaction trends. The oxidation of pyrite during the kinetic NAG test using H2O2 provides oxygen directly at the mineral surface, generating a measured oxidation rate for pyrite of 1.16 + 10-6 mol m-2 s-1, whereas the oxygen diffusion limited rate in the leach column air equilibrated reaction was of the order 10-8 mol m-2 s-1 as calculated from the GAMSPATH thermodynamic database. Results indicated that the oxygen derived from hydrogen peroxide had to be included as a reactant (eg a reacting mineral) in the simulation to account for the direct availability of oxygen at the sulfide mineral surfaces. Optical investigations identified the proportion, particle size, and surface area, of framboidal and euhedral pyrite in sample MS. The reactive surface areas of the two morphologies were very different (eg ratio: 5:1). To manage these two different pyrite morphologies the GAMSPATH thermodynamic database was updated to include framboidal pyrite, with similar thermodynamic properties and oxidation rate to euhedral pyrite but with a particle size based on the size of the individual internal framboid microcrysts. This modification, with framboidal pyrite reaction based on the size of its microcrysts produced results that correlated well with the kinetic NAG and column leach test results when the measured (kinetic NAG test rate) and calculated (column test rate) pyrite oxidation rates were employed. This provided some confidence that the model could be extrapolated to indicate longer-term geochemical reaction trends.

Jan 1, 2003