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By Bohrn W, Milionis K, Tessmer G, Reidetschlager J

The share of electric arc furnace based steel production is increasing - New technologies for the production of virgin raw materials for EAF production are under development and on the market - VAI has a strong position in the field of scrap substitution technologies with their COREX«-, COREX«-DR and FINMET«-technology. In late-1998 the steel plant SALDANHA was started up successfully. This integrated compact mill is using the COREX«-technology as hot metal and a combined DR-plant as DRI production unit. Also in 1999 the BHB FINMET« plant Port Headland went on Stream.

Jan 1, 1999

n One of the most interesting and economically important developments which has .`taken place- in the Kalgoorlie Field over the past twenty .years is the proved penetration of ore into - caicò schist. which:has been established on the North Kalgurli Mine. 'This is quite extensive, both. laterally and ' in -depth, and has occasioned-,'" ccasioned ' " some madification.of geological thought In the search for additional ore sources:. .Ore has been mined in calc schist almost since the' first major: gold::discoveries-were made,. and the principal 'features of the various types of depos:itl are well covered in the literature ' of the field. ' However, occurrences in caic schist have not-been characterised by the same degree of continuity or frequency as the innumerable lode formations in- the more -favourable quartz dolerite, ' and there has been a tendencyAo regard,them as isolated and discontinuous ore bearing structures, occurring only under very special-- conditions. It is not intended-:to describe the whole' range of caic schist ore occurrences in this paper, but only major controlling structures, whose penetration therein has been definitely established, and in which an appreciable .amount.of,_ore.has, been and is still being. found.. . It is considered that -similar stiiictiires: may present a' major objective for future exploratory work in other parts of the field'.

Jan 1, 1964

Legislation for control of ventilation in New South Wales coal mines is contained in the Coal Mines Regulation Act, 1912, as amended. The standards set down in that Act were based on the needs of the industry at the turn of the century. Changes and additions to the original standards have been made to cater for mechaniz- ation of the industry and the introduction of modern developments such as the use of diesel equipment. Technological progress has been recognized by the requirement for monitoring of machines and return airways. The passing of the Coal Mines Regulation Act 1982 has ensured that there will be a revision and modernization of the regulations affecting day to day operations of the industry.

Jan 1, 1983

By N Belluz, L Johnson, N Wiwoho, P Manning

The Kucing Liar skarn deposit is located in the Ertsberg mining district, which also contains other skarn deposits and the Grasberg porphyry copper û gold deposit. The Ertsberg district is located in the province of Irian Jaya, IndonesiaÆs easternmost province. Mining development began in the Ertsberg district in 1972 with the mining of the Ertsberg deposit. Daily production in the district now averages about 230 000 tonnes of ore, with the bulk of the ore coming from the Grasberg open pit and the balance from underground mining of skarn deposits. During 1998, 45 218 additional metres of drilling were conducted to delineate and understand the Kucing Liar orebody. The deposit was first intersected in drill holes in 1994 and then was intersected in underground workings located about 1000 metres from the discovery drill hole in 1995. Initially, the two intersections were thought to be different orebodies but are now realised to be different parts of the same orebody. The Kucing Liar deposit consists of magnetite û copper û gold replacement and skarn mineralisation in favorable Tertiary and Cretaceous units. The deposit is approximately 2000 metres in length and averages about 200 to 250 metres in thickness. The width varies from 400 to 600 metres. Drilling in 1998 was directed towards delineating the deposit on its NW and SE ends and to determine its down dip extension. Reserves for the deposit at the end of 1998 stand at 320 million tonnes at 1.4 per cent copper, 1.4 g/t gold, and 5.3 g/t silver. Many important questions remain to be answered concerning the relationship of the Kucing Liar orebody to the major faults in the district and to the Grasberg intrusive complex which contains the Grasberg orebody. Continued exciting developments are anticipated as work to understand the deposit by drilling and geologic study continues.

Jan 1, 1999

By P Hartlieb, M Noeger, M Varelija

Rock bolts are important in underground mining as they provide support to the rock mass around the excavation. They are the most common reinforcement method in mining and civil engineering excavations. The length of the bolts, types and spacing between them can be varied, depending on the reinforcement requirements and the use case (Kolapo, Onifade and Praise, 2022). The rock bolt provides safety and stability for the rock mass in the excavation area and they can be mechanically anchored, grouted, or friction anchored. They normally don’t have a measurement option and there is a possibility that it failed without showing visible signs on the surface, especially in grouted rebar bolts where they can still have some residual strength. Therefore, support functionality can be lost without recognising it. To overcome that, sensors can be installed on all three previously mentioned bolt systems. Intelligent bolts with implemented measuring systems have a function of showing changes and indicating if there is some damage on the bolt. So, it can be said that intelligent rock bolts are regular bolts equipped with additional instruments which are helping us detect potential instabilities inside of the rock mass or malfunction of the bolt itself. Changes in rock mass can be tracked, by measuring rock bolt reaction concerning the excavation response. Rock mass damage and instabilities are therefore measured in terms of rock mass deformation. Moreover, other additional information depending on the type of the sensor device could be collected. Based on such measurements, information about rock mass state can be derived. Different rock bolt types work at different reaction principles. Therefore, limitations on sensor application and information that can be extracted must be considered.

Sep 1, 2024

By M P. Schwarz

A major issue presently faced by companies producing and processing iron ore is the need to maximise throughput while minimising capital expenditure. While present high demand means this is of prime importance, the perennial issues of maintenance, operating costs, reliability, quality and environmental sustainability are also critical to profi tability. Attempts to address these issues generally require modifi cations to existing equipment, or trials of new equipment when designing plant for new projects.The risk involved can be substantially minimised by testing equipment improvements using advanced computational models prior to implementation. Examples of application of Computational Fluid Dynamics (CFD) and Discrete Element Method (DEM) modelling to sampling, cyclones, conveyor transfers, classifiers, dust control, banana screens, comminution and smelt-reduction will be given to illustrate the benefi ts of such an approach. *This is an abstract only. No paper was provided for this abstract.*

Jul 11, 2011

By T A. J Hopper, B J. Birt, K K. Trofimczyk

Nuclear magnetic resonance (NMR) has been utilised in the oil and gas industry for over 60 years. The technology was recently identified as having potential value in iron ore, where latent bound moisture may affect ore handling even after dewatering and extraction. The first step in introducing this technology to iron ore involved laboratory tests on drill core samples. These results established the parameters for a downhole borehole magnetic resonance (BMR) tool for iron-rich environments, which was subsequently developed. A major challenge involved shrinking what is a very large tool in the oil industry to a slimhole, lightweight, 1-man deployable mining tool.Of primary concern was the ability to measure the very fast transverse relaxation times (T2s) seen in the lab results on iron ore samples. Iron creates local field gradients that significantly decrease the T2 times. As a result, the BMR tool had to be able to measure T2s in the range of hundreds of microseconds, a level not required in clastic sedimentary formations. The choice of T2 cut-offs in iron ore is critical to successfully separating the free and bound fluids. The industry has typically focused on T2 cut-offs in clastics and carbonates, but not in systems with high iron content. Using core analysis results (poro-perm and NMR) we were able to verify the BMR response. The T2 cut-offs were determined from NMR core analysis and then applied to the logs so as to provide a continuous, calibrated permeability log.Field results that highlight the challenge involved in logging in iron-rich environments are presented, as well as some minimum requirements for a successful BMR log. Examples from boreholes in an active iron ore mine in the Pilbara iron ore province in Western Australia are presented, as well as explanations for how NMR data can be combined with bulk density logs to provide a continuous dry weight density log based on the original density-porosity equation from Alger et al (1963).CITATION:Hopper, T A J, Trofimczyk, K K and Birt, B J, 2017. Development of a slimhole downhole nuclear magnetic resonance tool for iron ore – some applications and limitations, in Proceedings Iron Ore 2017, pp 473–480 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By J Charbucinski

Commonwealth Scientific and Industrial Research Organisation (CSIRO), Exploration and Mining, has developed nuclear spectrometric techniques for borehole logging. The paper reviews the latest developments of this technology for the metalliferous mining industries. The SIROLOG logging system developed by CSIRO Exploration and Mining has been commercialised and is available to the mining industry.

Jan 1, 2000

Uranium minerals were found in Australia as early as 1869, but it was not until the 1940's that a search specifically for uranium was begun. Instrument types and techniques used in early exploration are still used today, but have been developed into more sophisticated and portable types. Recent improvements in exploration have been the introduction of the gamma ray spectrometer, radon sampling and geochemical surveys. The environments of presently defined uranium deposits are predominantly sedimentary. Known deposits in igneous environments are usually small. The size of targets which are likely to provide economic deposits is of the order of 10,000 tons U308, producible at a cost of less than $10 per pound. Such targets are most likely to be in Precambrian sediments or in granitic masses. Recent exploration in Australia has included investigation of Precambrian sediments, Precambrian and Palaeozoic granites, Mesozoic and Tertiary sediments, Precambrian volcanic rocks and brecciated masses of unknown age. The origin and method of emplacement of uranium in these environments is not well known but there are indications that syngenetic sedimentary processes are important, and volcanic rocks may make a major contribution to the supply of uranium.

Jan 1, 1970

By D Rubery, C Croker

The Boddington Gold Mine (BGM) is located 120 km south east of Perth, Western Australia. The operation is managed by Worsley Alumina Pty Ltd and mined by contractor Henry Walker Eltin (HWE). The mine has been operating since 1987 with ore extracted from a series of pits along strike. Ore is contained within the basement rock, which is overlain by a cap rock layer and transition zone. Cap rock and basement zones require blasting.As the mine neared completion, a high-grade deposit was discovered within 50 m of an existing Western Power substation and 100 m from the processing mill. The substation provides power to the Boddington area and is a back-up power supply to the city of Perth. Due to the delicate nature of the transformers located at the power station, overhead power lines and the mill, blasting in the area was considered very high risk. As such blasting needed to be controlled for flyrock, airblast and most importantly peak vibration and frequency limits which had the potential to damage the transformers.The mine was due for closure in March 2001. The decision to mine the pit was based on its high grade, ability to be blended with lowering grades from other pits and changing of the processing technique with the expansion. This decision extended the life for a further six months.Due to the high potential risks a detailed risk assessment was conducted by Orica, Worsley and Henry Walker Eltin. The completed assessment and the major design parameters were presented to Western Power for approval. The ability to reduce the blasting risk was focused on limiting of vibration through controlling maximum charge initiated per delay, blast timing and firing direction, and other innovative control measures. OricaÆs SHOTPlan« and Sabrex« computer modelling packages were used to predict the outcome of blasts.The success of this project has opened the doors for other high risk blasting projects, which otherwise may be left unmined.

Jan 1, 2002

The Earth Moving Equipment Safety Round Table (EMESRT) was established by mining companies in 2006 to influence manufacturer's equipment design through a process of engagement. 2010 EMESRT member companies include Anglo American, Barrick, BHP Billiton, Centennial Coal, Collahausi, Newcrest, Newmont, Rio Tinto, Vale and Xstrata.Driven by a persistent need for retrofits to new equipment, such as haul trucks, EMESRT initially engaged with Surface Equipment Manufacturers including Caterpillar, Komatsu, Leibherr, Hitachi, Le Tourneau and Terex. These OEMs responded positively to the EMESRT initiative, welcoming the opportunity for dialogue with an aligned industry regarding human factors issues related to equipment design, rather than needing to respond to the disparate range of demands for design modifications previously received from individual customers. This engagement process is about making global sustained changes within the OEM organisations and within the mining companies. It is a very international exercise. For example, over two weeks in September 2010, a total of 21 different miners from ten different companies travelled from Australia, South Africa, Canada, Brazil, Singapore and the United States to engage with OEM counterparts who assembled from the United States, Japan, France, Sweden, Finland and Germany. EMESRT Surface Group representatives completed a whirlwind tour of the major North American manufacturers of mining equipment. Starting in Dallas (Atlas Copco, LeTourneau), this tour passed through Gainesville (Sandvik), Newport News (Liebherr), Guelph - Ontario (Hitachi) and Milwaukee (P&H Mining/Joy Global; Bucyrus), before winding up in Peoria, Illinois (Komatsu, Caterpillar). Over nine meetings, this group engaged with 129 individuals from nine OEMs. The EMESRT group welcomed miners from four non-member companies to come along for the meetings. These companies are Syncrude Canada Ltd, the Kearl Oil Sands Project - Imperial Oil (ESSO), Suncor Energy Ltd and Teck Resources Ltd.Other mining industry sectors have now expanded the EMESRT scope from surface mining to include exploration and underground mining equipment. In 2009, EMESRT was organised into four Technical Groups, consisting of EMESRT member company representatives, to focus on engagement with OEMs of surface, underground coal and soft rock, underground hard rock, and exploration drilling equipment. An advisory group has been formed to coordinate activities between all workgroups and provide strategic direction and cohesion between all activities. The Minerals Industry Safety and Health Centre (UQ-SMI) facilitates and coordinates all EMESRT activities on behalf of member companies. Building on successes with individual Surface Mining OEMs, EMESRT now aims to help OEMs in their transition to a sustainable design process that will incorporate and address specific design philosophies at the concept phase of design, so that significant improvements can be made up front for little cost within the overall budget. EMESRT members plan to educate all stakeholders, internally, within their own companies, and externally, by addressing industry associations, regulators and other end users about new ways of evaluating equipment design based on EMESRT purchasing specifications. This presentation will outline the EMESRT approach and report on progress in 2010.

Dec 6, 2010

By J L. Mauk

Low sulfidation epithermal deposits are important sources of gold and silver, and are considered the extinct analogues of modern geothermal systems. The aerial extents of alteration halos that surround twenty-two epithermal deposits range from 4 to 315 km2, with many less than 60 km2. Deposits with alteration halos <30 km2 typically have well defined limits, whereas deposits with alteration exceeding 30 km2 are commonly complicated by overlapping alteration centres related to adjacent epithermal deposits or other deposit types (i.e. high sulfidation, porphyry). Irrespective of the physical coverage of vein or alteration halos, both large (>60 km2) and small (<20 km2) deposits can contain large amounts of gold and silver. The size ranges for twenty-one analogous liquid-dominated geothermal fields from around the world have a restricted size range of 5 to 60 km2 and irrespective of physical size, commonly have multiple zones of focused fluid upflow. From an exploration perspective the comparison between epithermal deposits and geothermal fields provide the following four important points. 1) Alteration halos surrounding epithermal deposits as well as those for analogous geothermal systems show a range of sizes, although most are less than 60 km2. Therefore, where alteration exceeds 60 km2 multiple vein systems related to several paleogeothermal systems are predicted. 2) Multiple upflow zones are common in geothermal fields of all sizes (5 to 60 km2) and although difficult to demonstrate in epithermal deposits there is a strong possibility of discovering several discrete adjacent mineralised centres. 3) The orientation of veins parallels the principle orientation of the surrounding alteration and where alteration is wider than the vein strike length, this could suggest the occurrence of adjacent veins. 4) The physical size of both veins and alteration zones is not important in relation to amount of contained gold, as both large and small can contain large amounts of gold. These conclusions provide insight into the physical size limits and hydrologic structure of these paleogeothermal systems and highlight the potential for multiple mineralisation centres within a single alteration halo.

Jan 1, 2004

By White L. R, Boger D. V

The paper describes the surface chemistry and particle physics that control the fundamental flow properties (Theology) of mineral particle slurries. We further address, through a series of case studies, the design data that emerges from experimental studies of the flow properties of complex, high volume fraction mineral slurries. The case studies are drawn from mineral oxide concentrate processes, tailings dewatering operations and from filter cake production and management. The paper emphasises the essential links between design of process slurry handling systems and the control of the flow of such slurries by control of the pulp chemistry.

Jan 1, 1992

By Emerson D. W

The search for economic mineral deposits is becoming more difficult as exploration goes deeper in the established mining camps and spread out to the surrounding covered areas, which may have an `overburden' some hundreds of metres thick. Geophysics is finding an ever increasing role in such exploration. When the target is zinc, the task often becomes even more difficult since sphalerite, the most commonly mined mineral, is non-magnetic, resistive, and relatively light compared to other sulphides. Fortunately, sphalerite commonly occurs in association with other sulphides, which are magnetic and/or conductive and/or heavy, thus most zinc-rich orebodies have at least one contrasting physical property to aid exploration. This paper presents the physical properties of sphalerite and other potentially important zinc minerals. Results of petrophysical measurements of samples from various zinc-rich ores are presented together with examples of geophysical surveys over a number of zinc deposits. The results show that the physical properties are not merely dependent upon the properties of the orebodies' constituent minerals. For example, the small (0.4 Mt) and low-grade (five per cent Zn + three per cent Pb + two per cent other sulphides) Flying Doctor deposit at Broken Hill, New South Wales (NSW) is much more conductive than the large (3+ Mt) and high grade (14 per cent Zn + five per cent Pb) Cadjebut deposit in Western Australia (WA). In the former case, tectonic stresses have

Jan 1, 1993

Study on a Novel Polymer/Bentonite Compound Adsorbent for Removal of Cu(II) from Aqueous Solution

Sep 13, 2010

By Raymond G. F

Geostatistics - a tool used by geologists and mine planning engineers to estimate grades and rapidly evaluate alternative mining strategies has reached an advanced stage of development for the silver-lead-zinc orebodies at Isa and Hilton Mines. Geostatistics has been used for over a decade in the massive copper orebodies but the stratiform lead-zinc orebodies are much more complex and provided a completely different set of challenges. Recent increases in computer processing speed and power provided by the Integrated Mine Planning System (IMPS) has aided the development of the geostatistics package. Also the formation of a project team and the subsequent in-house development which has drawn together the expertise of geologists, engineers and system analysts has contributed significantly to the success of the project.The most important feature of any approach to modelling the lead-zinc orebodies is that the kriging search must consider estimate and sample points according to their positions relative to bedding surfaces. By transforming co-ordinates as perpendicular offsets from a plane representing the local strike and dip, it is possible to elongate the ellipsoidal influence to parallel bedding. By interactively modelling surfaces using CAD facilities and then specifying these surfaces as 'hard' or 'soft' boundaries, the geologist has complete control over the kriging process.

Jan 1, 1993

By A G. L Pratt, M S. Kemp

BHP has used many innovative techniques when recruiting its workforce for the Cannington Project. Looking for a balance of experience and enthusiasm it was necessary to develop pre-selection tests to reduce the initial number of applicants to a manageable number for first interviews in Townsville. Success at this stage led to an applicant, and their spouse, to go through a second interview at the mine site. The full process from application to job offer took up to six months, but the results were felt to be worth the effort. The approach taken has resulted in a highly motivated and flexible workforce. This paper outlines the philosophies behind CanningtonÆs recruitment process, highlights some of the issues associated with the approach, and offers some measures of the outcomes.

Jan 1, 1998

By A G. Guinea

Every person in an organisation has what could be called ‘a different take’ on what it means to be a safety leader. The directors will tell you they are ultimately responsible for everyone’s safety and that they can be imprisoned as a consequence of a workplace fatality. Managers, take more of a focused approach and would explain that they are totally responsible for the safety of their teams. And then there are front-line leaders. Those that not only have the responsibility (like directors and managers) but they also have the accountability, and the ability, to influence how safely their teams work. But it is not just physical safety that leaders should be concerned with.

May 5, 2022

In submitting the accompanying sketch and description, the writer mentions that he has found this "gadget" a useful assay office adjunct.He believes that some millmen and assayers have been confronted, from time to time, with large samples of mill pulp for assay purposes and that although the commonly used method of coning and quartering dry sample is simple and effective, provided the samples are of reasonable proportion, the operator is frequently confronted with samples of pulp, sometimes up to 50 gallons. The writer stresses the advantage of being able to handle these samples. This fact inspired the design of the "gadget,"which was developed at the Kalgoorlie State Battery and has been found to give very reliable results. It has considerably eased the work of the assay office.Description. - A cone of suitable dimensions according to requirements (this one is about six gallons' capacity) is mounted on a light angle-iron frame and has a small hand-operated agitator paddle let into it far mixing purposes. The agitator and head frame are removable to facilitate cleaning. Four outlet pipes at the bottom at right angles to each other are controlled with one common plug, externally operated for discharging the pulp.Each operation of the machine delivers four equal parts; one or more of these can be used for further division as conditions require. Samples can thus be reduced to suitable assay room size in a few minutes.The dotted lines, enclosing the shaded portion, represent the four-bladed paddle.Each paddle is slotted with three parallel slots. Unshaded portions represent slots.

Jan 1, 1939

By I Lamb

Past experience of ground settlement and groundwater monitoring for tunnelling projects in Melbourne has provided an appreciation of the value and importance to owners of establishing a broad baseline monitoring program of the ground surface movements and groundwater movements well in advance of the commencement of any excavation and tunnelling activities. For the Northern Sewerage Project (NSP) tunnels in the northern suburbs of Melbourne, a baseline monitoring network of ground settlement points and groundwater wells was established in early 2006, 18 months prior to the commencement of project construction, and has continued throughout the tunnelling and project construction activities. This baseline monitoring network provides insights into the superposition and interpretation of both tunnelling and non-tunnelling effects, such as seasonal effects, which result in ground settlement.In the case of the NSP the baseline monitoring and construction phase excavations coincided with several years of drought. The reduced rainfall developed overall downward settlement trends project wide that could easily be mistaken at the local site level to be construction effects if the baseline monitoring was not available to show otherwise. There are lessons to be learned from the NSP experience for tunnel projects where there are variable surface soil types and where project-specific settlement criteria are to be established for the protection of property prior to construction.This paper presents examples of the baseline monitoring, how the tunnelling-specific settlement was identified and determined, and what this means in terms of how settlement criteria should be established and set for project consenting and in the construction contract documents.

Mar 8, 2011