Search Documents

By A Noack

Today underground infrastructures, like tunnels and especially wide spread underground mines, are often equipped with ethernet based communication systems. These networks are used for the unified communication of data, voice and video. As these networks stretch along the major tunnels and in increasing scale also into the production areas, a high degree of coverage can be reached. For wireless coverage, standard IEEE 802.11 WLAN access points are being used. In order to provide a maximum availability and reliability, the active components are equipped with battery backup power supplies and the network infrastructure is set up in a redundant way using ring or meshed topologies. This provides a much higher availability compared to traditional phone systems or dedicated data links using a conventional star topology.Distributed computing intelligence that is installed on active network nodes throughout the whole network, additionally supported by a central server system, creates the basis for new mine safety functions introduced in this paper for both coal and non-coal mining. These new safety functions cover the detection of potential emergencies, using the status of the network as a æsensorÆ, as well as dynamically guiding people to safe exits or rescue shelters in case of an emergency. Furthermore, these functions are of important benefit for improving the efficiency of search and rescue operations following a major incident or accident underground.

Sep 26, 2011

By O Arafat, K M. Bartholomew

A voracious consumer of energy and grinding media, the modern ball milling circuit has a huge direct cost impact on a mineral processing operation. Through optimisation, grinding also has the potential to unlock great improvements in recovery and throughput, but how can the complex interactions between mills, classifiers, tonnage, ore-type and downstream recovery be measured, understood and managed in a systematic manner?Functional performance analysis provides the tools and insights needed to measure, understand and improve the two key process efficiencies in ball milling circuits: classification system efficiency (CSE) and mill grinding efficiency.CSE measures the composite performance of the classification system as a whole. In short, the purpose of the classification system is to ensure that grinding mill energy is used to grind coarse particles while minimising overgrinding. CSE is simple to measure in the plant and it provides immediate feedback to the plant metallurgist, mill superintendent and management about the performance of the classification system and the amount of wasted energy in the grinding plant.Mill grinding efficiency measures the capacity of the grinding mill to convert feed-sized material into product-sized material on a tonnes per kilowatt hour basis. It is normalised based upon the ore resistance to breakage, so it provides feedback about the ‘health’ of the milling process under varying operating conditions and ore types. Mill grinding efficiency is measured at the same time as CSE through circuit sampling.Functional performance analysis combines CSE and mill grinding efficiency to provide a measureable, manageable optimisation objective. It also provides a link to tonnage, ore type and recovery. As a result, systematic optimisation of a grinding circuit is a measureable and manageable process to meet business objectives.CITATION:Bartholomew, K M, McIvor, R E and Arafat, O, 2014. Functional performance of ball milling circuits – a plant metallurgist’s tool for process characterisation and optimisation, in Proceedings 12th AusIMM Mill Operators’ Conference 2014 , pp 227–232 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 1, 2014

By L B. Sukla, V N. Misra

Microbial desulfurisation of coal has significant advantages over physicochemical desulfurisation processes since the former process selectively removes the inorganic sulfur compounds and heavy metals without significant carbon loss. The purpose of this study was to improve the desulfurisation yield of a coal sample from northeastern coalfields, Assam, India using microbial technique. The coal sample contained 2.13 per cent of total sulfur and 2.59 per cent of ash. Stirred tank reactors of 40 L capacity were operated in batch mode. Initially, the reactor was fed with 40 L of slurry containing ten per cent (w/v) coal, ten per cent (v/v) inoculum of mixed culture of mesophilic acidophiles, native to coal itself and the requisite amounts of constituents for 9K medium without added ferrous sulfate. The percolate of the reactor was then used to seed the medium for the next experiment. The purpose was to obtain a better adapted and more active biomass which would give a better desulfurisation yield for coal. Further studies were conducted in the bioreactor, fed with 40 L of slurry containing ten per cent (w/v) pulp density of coal, ten per cent inoculum (derived from previous studies) and the medium, supplemented with ferrous sulfate. Results showed an increased total desulfurisation yield of 43 per cent in the latter treatment in comparison to the previous one, where the desulfurisation yield was only 23 per cent. The findings also demonstrated the convenience of using inocula derived from coal, where 50 - 60 per cent of pyritic sulfur was removed, while chemical desulfurisation is of little significance with the majority of coal types. The ash content was also reduced to 1.74 per cent as the low pH of the process caused dissolution of a number of common minerals present in the coal.

Jan 1, 2004

Safe, efficient production is a common objective for all large open pit mines. Despite comprehensive policies, procedures and regulations aimed at protecting workers, several people die each year in mining equipment-related collisions. The limited sightlines of heavy equipment operators coupled with difficult operating conditions are major contributing factors to the majority of mining equipment collisions. Off road haul trucks are the most common type of machinery involved in surface accidents. These vehicles represent the primary target for improving safety performance by mine operators. Although several commercial products have been introduced to address these issues, none have achieved significant market acceptance. The current collision avoidance solutions lack integration with onboard fleet management and equipment health systems. To achieve acceptance in industry, any collision avoidance system must offer high reliability, minimal false alarms, and value for money. With these criteria in mind, this paper will examine the pros and cons of the various technological approaches to collision avoidance in an open pit mining environment. The unique global positioning systems (GPS) and camera-based proximity detection solution on offer from Modular Mining Systems will be described. This solution uses intelligent filters to minimise false alarms. Tight integration with fleet management provides context information to enhance warnings and enable back-office near-miss analysis. Available today, this combination creates a practical solution to improve the situational awareness of heavy equipment operators, at a compelling price point. Future directions for maximising heavy equipment operator situational awareness will also be examined.

May 1, 2010

By D Flint, K Vague

The Work Health and Safety Act 2020 (WA) (WHS Act; DMIRS, 2020) and associated Work Health and Safety (Mines) Regulations 2022 (WA) (WHS Regulations; DMIRS, 2022), supporting guidance materials and other laws, such as the Sex Discrimination Act 1984 (Cth) (SD Act), have imposed new duties on every person or business conducting an undertaking (PCBU) in Western Australia, including those operating in the mining industry. These laws and associated guidance materials combine to require owners, operators and contractors to discharge positive duties and better report and manage psychosocial hazards in the workplace. For mine operators, there is a positive duty to not only identify and eliminate hazards relating to psychological harm, sexual harassment and gendered violence at work, but to also report incidents to the safety regulator that could result in serious harm, even while internal and police investigations are ongoing. Traditional mines safety teams are navigating the evolving frontier of psychological and gendered safety as the duties relating to psychosocial safety and sexual harassment at work continue to expand. This paper will review the legal obligations on PCBUs to conduct internal investigations into critical psychosocial incidents and gendered violence on mines, whilst balancing the demands and sensitivities of investigations by the safety regulator and police. There are emerging approaches to safety investigations that can aid PCBUs in managing their investigations of psychosocial incidents and gendered violence, including trauma-informed investigation techniques, collaboration with psychological experts and the use of limited legal privilege. Well managed and sensitive investigations can foster trust amongst workers, result in improved incident reporting by workers and lead to enhanced safety outcomes for the resources industry whilst preserving the legal positions of involved PCBUs. Specifically traversing the new duty to consult, cooperate and coordinate, this practical session will arm mine managers, safety professionals and human resources professionals, from mine operators and mining contractors alike, with tools and processes to bring to safety investigations, particularly on residential mine sites.

Apr 16, 2024

During the past eight years a vigorous drilling campaign resulted in large increases in the reserves of both copper and silver-lead-zinc ores.As a result the Company initiated an increased production programme.Some major capital works have been completed, others are in progress and more are needed to achieve the proposed daily throughput of 14,400 tons. The increased ore potential justified a copper refinery which has been constructed at Townsville. The increased production rate achieved to date, combined with improved techniques and greater mechanization, is assisting the Company to combat the general inflationary trends caused by increased costs for labour and materials.INTRODUCTION"Today we are armed with better weapons in our fight for lowered costs and greater efficiency, but we must not flag in our efforts to improve." Such was the resolution expressed by Mr. K. B. Gross, then General Manager of the Company, in his review lecture delivered to the First Ordinary Meeting of The Australasian Institute of Mining and Metallurgy at Mount Isa on 18th August, 1952. This present review of the period 1952 to 1960 records our efforts to fulfil this resolution. At the th:ne of Mr. Gross's statement,copper production was commencing in earnest. Although the importance of Mount Isa's copper orebodies was well recognized, the major discoveries which led to Mount Isa's emergence as Australia's premier copper mining and smelting operation were not known. These ore discoveries and their subsequent development are the major factors which warrant a further review of the Company's progress.The increased magnitude of the Company's operations is illustrated on graphs of Tons of Ore Treated (Fig. 1), Metals in Products (Fig. 2), Water Consumption (Fig. 3)...

Jan 1, 1961

By C M. Rebagliati, J G. Payne, K Roberts

The Pebble deposit, located in south-west Alaska, is one of the largest Copper- Gold-Molybdenum (Cu-Au-Mo) porphyry systems in the world, with a current resource of >8 billion tonnes which contain 73.7 billion pounds of copper, 87.1 million ounces of gold and 4.16 billion pounds of molybdenum. The Pebble deposit formed at ~90 Ma, during emplacement of subduction-related hornblende granodiorite porphyry intrusions emplaced into Jurassic-Cretaceous sedimentary, volcanic and subvolcanic intrusive rocks of the Kahiltna Terrane. The Pebble West and Pebble East Zones represent two thermal and fluid centres in a single large magmatic-hydrothermal system. The West Zone extends from surface to about 500 m depth, has thin zones of oxide and supergene mineralisation overlying hypogene chalcopyrite mineralisation, and is amenable to open pit extraction. The East Zone extends to at least 1700 m depth, is higher grade, occurs beneath an eastward-thickening cover of younger sedimentary and volcanic rocks, lacks oxide and supergene mineralisation, and is being evaluated for underground block-cave mining. Most Cu-Au-Mo was introduced with early K-silicate alteration and related quartz-sulfide veins. In the East Zone, a structurally-controlled overprint by advanced argillic alteration significantly increased Au and, to a lesser extent, Cu grades. Exploration potential at Pebble and its surrounding district remains high. Several other porphyry, skarn and epithermal deposits have been discovered in the district, but only limited exploration has been conducted. The eastern, higher grade part of the Pebble deposit remains open in several directions, with significant potential for resource expansion by ongoing, aggressive drill exploration. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

By C B. Valentin

It is acknowledged that the analysis of iron ores using X-ray fluorescence (XRF) for major and minor elements is best carried out on fusion discs. This method of sample preparation eliminates mineral and particle size effects which can lead to biased results when using pressed powder pellets. However, the fusion disc method is costly as it requires a high capital investment in platinumware, requires experienced operators and uses expensive fluxes. Also, the dilution effect complicates the analysis of trace elements. For many applications, such as exploration and mining control, the method of XRF analysis of iron ores by pressed powder pellet probably provides data of adequate quality. Kumba Iron Ore, an iron ore producer in South Africa, recognises this and carries out most analyses of iron ore by pressed powder pellet and uses the automated fusion method mainly for certification of in-house calibration standards and quality control (QC) samples that are used for validation of pressed powder pellet method purposes. Automated fusion is also used for analysing the composite export shipping samples. All the other exploration, production, despatching and plant operation samples are done by the pressed powder pellet method. Automation of sample preparation procedures should improve the quality of data for pressed powder pellets. To compare the precision of the three methods of sample preparation and XRF analysis, 20 aliquots of a QC standard were prepared and analysed by each procedure/preparation method. The results and statistical data on the most important elements, Fe, K2O and P, are as shown later in Table 2.Clearly the precision is best for the auto prepared fusion discs, as expected, and worst for the manually prepared pressed powder pellets. However, the data generated from the auto prepared pressed powder pellets compare remarkably well against those from the auto prepared fusion discs.

Jan 1, 2007

By Littlewood E

We offer these notes as a practical contribution. All the arguments we advance have been tested by practical experience.In its preparation we realised that our subject was one of such importance and covered so wide a field that, dealt with by one of us alone, it might easily have been too much for him, so we have endeavoured, by mutual criticism and advice and a pooling of ideas, to bring forward a few points that may be of advantage to members. If any of the paper is of benefit to mining on the "Golden Mile," or elsewhere, we shall feel amply repaid for our efforts.It is obvious to all that the longer the machine is working productively per shift the greater the return, to all concerned; the machine-man himself and the company. Furthermore, if a man commences a shift with a definite objective in view; for instance, to bore and fire a specific cut, which he recognizes will give him a good financial return, then that man will exercise all his capabilities to attain that objective.In this paper we hope to demonstrate the value to the machine-man of the knowledge of the capabilities of each hole he bores, so that he will be enabled to utilize his drilling time to the greatest advantage. Also, we hope to show that such drilling time can be advantageously extended.After the war, with the influx of new men to the industry, some education on the finer points of machine work may be desirable, and any instruction in this branch must stress the realization of the value of each hole.We realise that most of those present have a sound workable knowledge of machine-mining, and we are not trying to teach anyone the fundamentals of machine work, but we would like to bring to their attentIon some of the finer points which we believe are very important.The machine-man has control of gear of a capital value of over £150, and the use or misuse of that material has a direct bearing on working costs. Therefore it is imperative that the capital outlay is gainfully employed.A "bogger" in charge of a 5/- shovel engaged unproductively is bad enough. How much worse for £150 worth of gear to be not fully productive.Figs. 1 and 2 demonstrate angles of break, and the full realization of the importance of this angle is essential to our paper. Although these Sketches are two-dimensional, we hope they will be sufficient to demonstrate our meaning. We will pass over them as briefly as possible.Fig. 1 shows three holes asked to perform an identical task.(a) 7-ft. hole bored 2 ft. into solid ground-will not come out.(b) 4-ft. hole bored 1 ft. from solid ground-will come out easily.(c) 5-ft. hole bored to solid ground-the best that can be expected under general conditions encountered.The angle of break is a right-angle, normal to direction of hole.

Jan 1, 1944

The Australian Constitution specifies certain powers of the Commonwealth Government to be used in its capacity as the national government. Certain of these broad powers result in the Com- monwealth having a facility to play an important part in the development of the mining industry. The State Governments, however, by virtue of their wide powers to regulate matters within the boundaries of a particular State, are more directly involved in the day to day administration and standards of activities of mining operations. In this respect the Common- wealth has something of a dual role because of its "State-like" responsibilities for the mainland Terri- tories. The components of the role that the Common- wealth Government discharges in relation to the mining industry are qualified to varying extents at particular times by the political persuasion of the Government. In absolute terms the components are as follows. 1. Economic management. The Commonwealth's fiscal and monetary policies have an important effect on industry as well as on State finances. In particular, the taxation regime employed by the Commonwealth Government is of direct importance to economic decision-makers in the mining industry. 2. International matters. International trade and commodity matters are, more and more, becoming an everyday part of the conduct of a nation's foreign affairs. 3. Exports. The Commonwealth Government, via the constitutional powers over overseas trade, have exercised varying degrees of control over mineral exports to achieve particular objectives. 4. Foreign capital and investment. Australia in general, and the mining industry in particular, is and will continue to be a net importer of capital. There appears to be bipartisan political agreement in Australia that foreign investment policy must be enunciated to ensure that investors. are in no doubt that Australia welcomes beneficial investment and technology from overseas. 5. Environment and Aborigines. Governments, both Commonwealth and State, have in recent years become more involved in these areas in response to their interpretations of community aspirations. 6. Energy. Access to assured supplies of energy is now viewed, by Governments worldwide, as a desirable asset to ensure the well-being of a nation's people and industries.

Jan 1, 1978

The paper gives details of the reasons why attention was directed towards the modification of flotation cells. The cell volume and impeller speeds were reduced, and it is estimated that the power consumption for lead and zinc flotation will be reduced by about 2·8 kWh per ton of ore treated, and that substantial savings will be made in maintenance costs. The metallurgical efficien.cy of the operation has been maintained and attention is now being directed towards the improvement of grades of concentrates and recoveries of metals.INTRODUCTIONIt was on 1st August, 1934, that the first Denver No. 21 flotation cells were operated in the treatment plant of The Zinc Corporation Limited, in a pilot Nant which had been installed to determine the economics of all-flotation as against the then existing gravity and flotation practice.The ore being mined at that time came from the lead lode which consists of a granular mixture of galena, marmatite, chalcopyrite, tetrahedrite, pyrrhotite, pyrite and lollingite with a gangue association of calcite, quartz, bustamite, rhodonite, manganhedenbergite, garnet, fluorite, manganocalcite and apatite. The silver content of the ore occurs in three minerals-tetrahedrite, dyscrasite and pyrargyrite, the last two mentioned occurring in microscopic association only.A parallel lode, known as the zinc lode, was well developed at that time. The common lead lode gangue minerals-calcite, rhodonite, bustamite-were rare in the underground exposures of the zinc lode. No metallurgical work was done on this ore during the pilot plant operations although since then both lead and zinc lode ore have been treated.Early in 1936 plans were made for the complete re-organization of the mine operations, and in view of the metal-

Jan 1, 1956

Welcome to Mount Isa- my home city and without doubtthe base for what promises to be the most exciting mineral development yet seen in Australia.Mr. Chairman, it also gives me great pride to representthis area in the Queensland State Parliament as well as being the Minister for Minerals and Energy in the Queensland Government.Mount Isa is now part of the Australian mining industry folklore.It is all what a good mine is all about. It is. all what a good community is all about.

Jan 1, 1993

By C Li, S Wang, L Qiao

Jinchuan nickel mine is the largest nickel mine in China. Cut-and-fill mining method with high density cementing materials is used in the mine. The original mining design divided the mining operation into two steps. The first step stopped the mining rooms and the second step stopped the pillars. Because the two-step method made big trouble for finally mining pillars and strongly limited the mining speed and production, it was successfully changed to a continuous cut-and-fill method without pillars. However, the mining operation in the mine has been down to 800 m and the mining condition is getting worse and more complicated. Through systemetical field investigations and 3D FEM analysis, it is proved that the mining method without pillars is feasible for mining deeper orebodies in Jinchuan nickel mine.

Jan 1, 2000

By D Xiong, G Xu, L Yao, F Wang, Y Duan

The goal of this project has been to digitise and use drill parameter data from rotary drilling (measurement while drilling; MWD) for a more effective planning of the blasting process in surface mines. A more accurate and reliable digital drilling and automatic hardness identification technology was developed, which includes both a hardware and software system. In the aspect of hardware, we designed a positioning, navigation and hardness perception terminal system which consists of a global positioning system original equipment manufacturer board, programmable logic controller and sensors of measuring major parameters, and a wireless data transmission system which combines digital blasting platform and wireless transmission facilities. In the aspect of software, we developed the navigation software of locating blastholes using LabVIEW and C++, and the blasthole design software using AutoCAD ActiveX (C#) technologies. This new technology is applied at Jiangxi Dexing Copper Mine, and initially realising the digitisation of drilling and hardness identification in blasting zone.CITATION:Duan, Y, Xiong, D, Yao, L, Wang, F and Xu, G, 2015. Advanced technology for setting out of blastholes and measurement while drilling, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 593–598 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By J J. Cilliers

The aim of this paper is to give an overview of the FrothSim flotation simulator and to demonstrate its ability to predict the performance of real flotation circuits. Example simulations are presented in which the feed rate to the circuit is varied, followed by simulations in which a cleaner section and recycle loop are added to the rougher bank.The simulator is able to predict both the recovery and the grade produced by the cells at all locations in a circuit and the simulator is shown to produce plausible grade recovery curves. It also demonstrated that the performance of banks of cells improve as the feed rate to the bank increased (improved grade for a given recovery), but that more cells are required to give the same overall recovery.

Jan 1, 2005

By K M. Watling, F M, G K. Parker

Surface enhanced Raman scattering (SERS) spectroscopy at surfaces under electrochemical control has been applied to elucidate the adsorption of thiol collectors. SERS spectroelectrochemical studies at coinage metal electrodes have been carried out on ethyl xanthate and three iso-xanthates, O-isopropyl-N-ethylthionocarbamate, 2-mercaptobenzothiazole, diisobutyl- dithiophosphinate and butylethoxycarbonylthioura. For each collector, adsorption occurs via charge transfer to form a metal-sulfur bond and, in situations for which the reversible potential of the formation of the bulk phase is known, at underpotentials.

Jan 1, 2005

Silica and limestone fluxing levels in copper smelting slags were studied. Copper concentrates with flux additions were smelted to matte (55.5 per cent Cu) and slag in a pilot scale submerged combustion furnace.Results indicated that oxidic and sulphidic copper levels in slags were minimised with a slag Si02 level of 36 per cent and a SiO2/CaO ratio of 5.5. Total copper losses in slags were 0.6 per cent under these conditions.To produce the desired slag chemistry, additions of bulk silica and limestone to copper concentrates of fluctuating grades were predicted numerically. The method employed the solution of two simultaneous equations, each respectively for silica and limestone calculations.The predicted flux additions were applied in a further series of tests and the resultant stages were found to be satisfactory. The method is applicable to smelting 'operations which employ two flux bins, with weigh feeders, so that slag chemistry may be controlled with the flux/concentrate feed mix.

Jan 1, 1985

In order to fully understand why Amax Coal puts such extreme emphasis on the drilling and blasting programs at each of our mines, we must review the past. This paper will discuss the drilling and blasting techniques we used in the 1970s and their evolution to current practices. As time progressed, major changes influenced the surface mining of coal through new more restrictive governmental controls and local communities organising into groups with two goals in mind, one to shut down the mines and the second to try and get rich by making false and unjust damage suits against the mines. In virtually all of our midwest surface operations we have at one time or presently are facing litigation that has reached into the millions of dollars. Amax Coal has worked in co-operation with the United States Bureau of Mines in the areas of blast vibration, shot design, highwall safety, blast casting studies and many more. Today we are continuing to work with Dr David Siskind and his expert staff seeking answers to old and new problems addressing the blasting of overburden and parting seams.

Jan 1, 1995

By S DeKruijff

The Mount Isa Mines Copper Mine in Mount Isa started producing copper in 1966. The Copper Mine gradually increased production rates to nearly six million tonnes per year. Over the last three years the mine has been in a gradual ramp down due to the reduction of primary ore sources and head grade. The majority of ore sources are predominantly in pillar retreat sequences bounded by multiple fill masses. There also a substantial lower grade resource delineated to the south of the main orebody. These remaining ore sources present significant engineering challenges to obtain a safe and cost-effective extraction. Stope designs have become increasingly complex and require additional engineering and operations input and analysis. This paper describes the major planning and operational challenges and issues associated with the stope design and extraction of an orebody in the later stages of mine life.

Jan 1, 2000

By D Brereton, C J. Moran

Intensive resource extraction, in the form of multiple mining operations, presents significant assessment and management challenges for resource developers, governments, community and the environment. Cumulative impacts, ie the successive, incremental and combined impacts (both positive and negative) of an activity on society, the economy and the environment, can place significant pressure on social, economic and environmental capital and render conventional mine-by-mine approaches to management ineffective. Cumulative impacts can be what are most important to environments, communities and economies surrounded by multiple mining operations because cumulative impacts are what they experience. There is much to gain from increased consideration of cumulative impacts. Unmitigated impacts have the potential to delay or even prevent expansion of mining in existing and prospective areas. On the other hand proactive management of cumulative impacts can benefit regional environments and communities and contribute to the industryÆs social license to operate. Resources are often not the limiting factor to better cumulative impact management. More effective coordination of existing resources may go a long way toward mitigation and enhancement, and better planning and assessment may help avoid impacts and exploit opportunities for efficiency gains through reduced duplication. In this paper we draw from working examples to present five practical assessment and management strategies applicable to resource companies to enhance positive, and avoid and mitigate negative, cumulative impacts. The strategies are presented based on their capacity for achieving outcomes, ease of implementation and cost effectiveness and are drawn from a multi-year study on the assessment and management of cumulative impacts in the Hunter Valley, New South Wales and a follow-up study to improve cumulative impact assessment and management practice in the Australian coal mining industry, both reported elsewhere.  

Jan 1, 2009