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By A R. Hollis, M Heddon

The safe life cycle of a Tailings Storage Facility (TSF) is founded on the fundamentals of proper design, construction, operation and closure. Leinster Nickel Operations (Leinster) utilises four active TSF cells that are cycled between filling (deposition), desiccation, and construction to meet a targeted rate of rise. This results in ongoing and consistent raising of the TSF walls. Critical to maintaining the safe life cycle through this consistent wall raising is precision construction and high frequency quality assurance to ensure compliance to design requirements and TSF walls free from defects. Leinster has recently deployed Intelligent Machine Control technology for TSF construction. Advances in Intelligent Machine Control have decreased variability in construction; ensuring variations are within the tolerances of design. The Intelligent Machine Controls are programed to ensure construction conforms to design tolerances of +/-30mm. This level of accuracy provides assurance of borrow area set out, compacted layers are as per design, compaction monitoring is within the zone placed, scarification between layers to prevent lamination is maintained, and batter angles are set to the correct grade. This level of control provides certainty that construction meets the design intent. In conjunction with Intelligent Machine Control, periodic drone surveys are conducted to verify construction against design. Advancement in survey equipment and techniques allow higher frequency, high accuracy survey to be completed on demand by site based personnel. This provides quality assurance through all stages of the construction phases, as well as the final constructed wall, ensuring compliance to design. Combining Intelligent Machine Control with higher frequency quality assurance provides an increased level of certainty that the TSF construction is defect free and within quality specifications. These recent technological advancements in Construction and Quality Assurance ensure cell raises are constructed to the design intent with greater levels of accuracy and precision than ever before.

Jul 1, 2021

By Hawes GW

Until 1980 copper, lead and zinc sulphide slurries have been success- fully dewatered for rail and sea transport for many years at the Rose- bery site of North Broken Hill Holdings Ltd. utilizing conventional vacuum disc filtration systems. An upgrading and mill expansion program completed in 1981, which also permitted the introduction of ore streams changes, had resulted in difficulties dewatering copper and lead sulphide slurries to comply with transportable moisture limits. Following an extensive investigation which included both laboratory and pilot plant testing a program was commenced to replace the 2 vacuum disc filtration systems with 2 pressure filtration systems for use on copper and lead slurry dewatering and also to retain other existing vacuum disc filters as standby. An analysis of mill operations performance resulted in slurry storage tanks with a capacity equivalent to 20 hours of normal production being incorporated into the project. The pressure filters are mounted above the concentrate stock- piles. A sealed sloping floor incorporating launders is used to prevent any accidental contamination of the concentrate from pipe leakages, spillage, or from water hoses used for clean up purposes around the area. The project was completed in 1985 and operating performance has been better than that predicted from testwork. Equipment availability at 95076 together with the slurry storage capacity provided results in minimal requirement for the standby vacuum filtration system. Some typical operating results are given.

Jan 1, 1988

The introduction of gravimetric sampling of respirable dust in the mining industry ne- cessitated the standardisation of techniques. The paper reviews the legislation con- trolling respirable dust monitoring for risk assessment purposes, it discusses the actions taken to introduce gravimetric sampling in collieries and it summarises the proposed guidelines. In conclusion, some of the results of dust surveys conducted in accordance with the proposed strategy are discussed.

Jan 1, 1988

By F Faraj, M Pal, M Haest, M Bradshaw, H Lang, K Hume

MineSense Technologies Ltd. is revolutionising grade control at mining operations by installing ShovelSense® sensors on buckets that measure the grade of every load before it is dumped in the truck. This allows the mine to exploit grade variations at a resolution that was not available before, reducing the amount of ore loss to the waste stream and removing waste from material destined for processing. These changes dramatically improve the profitability and sustainability of mining operations. ShovelSense relies on X-ray fluorescence analysis of the rocks as they flow in the bucket and is integrated with fleet management to direct the trucks to the right destination. Lab simulations of ShovelSense measurements on porphyry copper ores show correlations between predictions and lab measurements at 0.98 r-squared with a coefficient of variation of 10 per cent. Visualisation of copper grade predictions in three dimensions shows a reasonable match with the dig plan, but with local changes in the ore-waste contact due to more accurate contact identification, related to blast movement and other mining factors. Correct delineation of these contacts ensures ore trucks are not sent to the waste dump and waste trucks are diverted from the crusher, creating enormous value for the operation and the environment.

Mar 22, 2022

THE reduction of iron from the ferric to the ferrous state prior to its titration by permanganate or dichromate may give erroneous results in the presence of other reducible metals such as titanium. Stannous chloride and metallic zinc both reduce tetravalent titanium to a lower form, and so increase the consumption of the oxidizing standard: solution. Sulphuretted hydrogen and sulphurous acid do not reduce titanium, but are slow in action and troublesome to manipulate.Sulphuretted hydrogen is considered to be the best reducing agent for iron in the presence of titanium.* In the method to be described the advantages of the H 2S reduction are retained without the disadvantages of using the gas. The reduction is carried out by the action of a metallic sulphide having a solubility product of such a value that the sulphide iom, are utilized as fast as they are formed, and but little free sulphuretted hydrogen is given off.Cadmium sulphide was the first to be tried, but its solubility product (3.6 x 10 - 2~)t was apparently too low. The reduction was satisfactory, but the excess was very difficult to remove. Zinc sulphide (S.P. = 1.2 x 10 - 23) was found to be quite satisfactoryin both respects. The zinc sulphide is preferably used in the form of an emulsion prepared from pure zinc sulphate as follows: About 100 grm. of ZnS047H20 is dissolved in 2 litres of water. H2S is passed until no further precipitate is obtained, the acid formed being barely neutralized from time to time by the addition of ammonia. The precipitation of the sulphide in a slightly acid solution gives a finer emulsion than that prepared in an alkaline solution, and any iron present remains dissolved. The precipitate is allowed to settle and the clear liquid decanted. The precipitate is then shaken up with more water, acidified with a little sulphuric acid, allowed to...

Jan 1, 1922

Many of the discrepancies that appear when comparing the results of reducing machinery are due to the nature of the materials reduced and the conditions under which they have been treated. It is therefore necessary that manufacturers should employ standard materials in their tests that sufficiently approximate the substances to be ultimately treated if the information is to be of any value to the purchaser. Another advantage to be gained by employing universal standard materials is that by their means one is enabled to compare the relative values of different types of machines. At present much of the data meted out to the public is insufficient to enable them to judge fairly. Of course the best test would be to send some of the stone tor which the machine is required, to be treated by the various crushers in the market that are likely to be suitable for the purpose, but this is not always possible. It would not take long to become accustomed to judge of the value of a machine for a specific purpose if it was guaranteed to work a certain quantity of some standard rock, even if that standard were not identical with the material to be treated.There are many points to be considered before selecting a machine, such as the size of the rough stone it will take, the size to which it will reduce it the proportions of various grades made when crushing to pass through a given mesh the form of the delivered particles the time taken to treat a+ certain quantity the horse-power required to drive the machine, both when loaded and unloaded whether constructed to crush wet or dry the wear and tear of the machine its total weight and weight of the heaviest part the cost of machine what attention it required whether the wearing parts are readily replaced, and several other points common to all machinery. 'When considering these varying quantities, we can tell at a glance certain machines that are suitable for a particular sort of work, and can then compare those belonging to the same class, thus avoiding errors made purposely or through ignotance by persons interested in different machines, who frequently compare machines originally constructed for.

By D A. Collins

The floatability methodology developed by the AMIRA P9 project through research contributions by the Julius Kruttschnitt Minerals Research Centre (JKMRC, Brisbane, Australia), University of Cape Town (UCT, Cape Town, South Africa) and McGill University (Montreal, Canada) has been successfully commercialised through JKTech. The methodology involves detailed flotation plant campaigns which require large quantities of data to fit models that can be used in JKSimFloat (a steady state simulator for the flotation process). The methodology to date, although widely accepted as the best flotation optimisation technology available, is limited to existing circuit optimisation and requires full plant or pilot plant data to calibrate new models. The floatability of new ore types cannot be characterised using this method unless a pilot campaign is undertaken. After reviewing a large database of existing industrial floatability data, a new methodology is proposed that involves a laboratory based flotation test procedure and review of the floatability database to characterise the floatability of new ores. The full methodology is labelled the floatability index test procedure (JKFIT). This paper outlines the JKFIT procedure and the results of applying this methodology to pilot plant data from a copper ore. JKFIT was applied to two different feed sizes (namely a P80 of 180 microns and 212 microns) of this copper ore. The results of applying JKFIT to this case showed that the metallurgical response (in terms of grade and recovery) from the full pilot plant survey data could be predicted well. Further validation of this methodology was conducted on a separate copper ore. The results from this validation also showed that the JKFIT test was able to be used to predict the full plant performance. The JKFIT test has the potential to become the 'drop weight' test of flotation which will improve the confidence in plant design flow sheet layouts, allow full orebody characterisation and prediction of key grades and recoveries before the ore enters the plant, and will provide an improved methodology for chemistry impact analysis on different ores.

Jan 1, 2008

The complete life cycle of a production facility has many phases requiring many different skills and many different personalities. It is not unlike the life cycle of a person and many parallels can be drawn from it. I leave some of these analogous situations to your fertile minds. The author, having worked in operations, plant design, plant commissioning, marketing and many other interesting situations through the industry has drawn from this experience and examples given by many associates in the industry.The phases seen are as follows: Concept Studies û someone has a bright idea of how to make a dollar. Scope Studies û what possible processes/options that could make a dollar. Prefeasibility Study û the æviableÆ scope options are studied to develop feasible options. Feasibility study û defines the concepts that should be designed to make a viable project thus enabling financing and project commitment to be made. Detailed Design û an intermediate step that consolidates the inputs to give a robust plant that can be constructed.Construction û people can see what they thought was going to occur and start to understand the plant. Commissioning û the hand-over of æownershipÆ from the conceiverÆs to the operators. Operations û the ætoyÆ has become reality and money must be made. De-commissioning û the plant has seen out the useful life of the ore deposit, it now goes through a further process required by society.Across these phases of plant design run several countervailing management requirements that can influence the outcome of the plant design. Some of the management rigours that have to be applied to the various phases are as follows: costing basis of the various phases; operational and maintenance reviews; sustainable development; risk assessment; reliability reviews; equipment availability; commissioning time; and environmental review.This paper endeavours to awaken people to the phases that projects require for a successful outcome and the management rigour that has to be applied throughout the phases to ensure the correct intellectual horsepower is applied at the right time to ensure the best outcome.Many of you would be parents and realise this is not unlike the development of children, teenagers, adults, retirees and ongoing.

Jan 1, 2002

A non-contacting under-belt capacitance and gamma-ray backscatter technique has been developed for the on-line measurement of moisture in coal. In this technique, moisture was correlated with radio frequency susceptance and conductance determined using an under-belt capacitance sensor in which a fringing electric field Interrogates a layer of coal on the conveyor belt directly above the sensor. To compensate for variations in the density and thickness of the coal layer, an under-belt gamma-ray backscatter gauge was used to measure an equivalent volume of coal.A plant trial of the technique was conducted at Stockton Borehole Colliery, SW Australia, where the gauges were installed on the coking coal product conveyor. Product moistures, in the range 7 - 14%, were determined with r.m.s errors of 0.50 and 0.25 wt% using on-belt and static off-belt gauges, respectively. The difference in the on-belt and off-belt gauge measurement accuracy was attributed to sampling errors in the calibration of the onbelt gauge.

Jan 1, 1989

By Fisher AEJ

On Sunday morning 7th November, 1976, at approximately 2-25 a.m., smoke was discovered issuing from the 1912 m long belt drift at Appin Colliery. A Clouth steel cord rubber belt approximately 940 mm in width had been installed in the drift in 1963 on the basis that no fire resistant steel cord belt was then available to operate on a single lift at the load and on the 160 gradient of the drift. Investigation showed that the belt drift was on fire and the usually downcasting drift was upcasting. Immediate fire fighting and rescue operations were instituted and the drift was sealed off. High expansion foam was pushed into the drift from the surface and the fire was brought under control. Recovery work resulted in the fire being put out and the drift open for walking traffic by, S-P0 am., on Wednesday 10th November, 1976. lie experience gained during the fire fighting and recovery operations led to recommendations in regard to future use of high expansion foam.

Jan 1, 1981

The South Mine, property of Broken Hill South Limited, is situated at Broken Hill, NSW, Australia, towards the southern end of the main lode. The leases (MLs 7 and 8) cover a length of 2400 feet along the lode outcrop and the workings extend, at this date, to a depth of 1940 feet below the collar of the original main shaft and to 825 feet below sea level. Mining operations have been continuous for about 58 years and during this period nearly 12.5 million tons of ore have been mined. The monthly tonnage extracted approximates 30 000 tons in normal times.The ore is a mixed sulphide containing galena and marmatite; the gangue minerals are principally calcite, rhodonite, quartz and garnet. A typical assay for a monthly period is 14.4 per cent Ph, 5.6 ozs Ag, and 11.6 per cent Zn. The whole of the ore is concentrated on the property by combined gravity and flotation methods. The lead and zinc concentrates produced are railed to other centres for the extraction of the contained metals.

Jan 1, 1994

By J Santana, V Ferraz, G Pinto, G Cruzado

Morro Agudo is an underground zinc and lead mine owned by Nexa Resources. The mine uses room and pillar as the main mining method. The recovery of pillars as well as the opening of new excavations using sublevel stoping as mining method has been studied. On some occasions, the need to recover pillars and open a stope by using the sublevel method happens in a region that is already excavated or in deeper areas than those mined so far. These changes represent a major geotechnical challenge due to the complex openings of the mine and interaction between two different mining methods. Historically, geotechnical mapping, kinematic analysis and a 2D numerical model were used to evaluate the new mine openings, and in 2021, 3D numerical model was introduced, which enabled global and local assessment of new excavations impact and the stability of openings after recoveries. The 3D model, made with MAP3D, is used to evaluate each pillar to be recovered, considering the spans of the resulting openings, the ideal sequencing of removal to maintain stability, in addition to the impact and geometry of the pillars left in the chambers. Pillar recoveries done in 2021 and the impact of it on the pillars left were the sources of the back analysis to calibrate parameters inputted on numerical model to assess recovery on new chambers and Phyllite has been considered into the model and it has been a source of instability due to its parallel position to roof of room and pillars and stope hanging walls.

Nov 29, 2022

By R Lloyd

Coal Services (Health and Safety Trust) funded ARRB Transport Research Ltd to investigate fatigue and performance of truck drivers over consecutive shifts. The main questions were to assess: What is the most important contributor to acute fatigue in mining? Is it length of shift (eg eight hours versus 12 hours) or is it time of day (eg circadian effects)? What is the limit of successive day or night shifts before chronic fatigue affects operator performance in open cut mines? The project methodology included utilising ARRB Fatigue Monitoring Devices (forced-choice stimulus reaction) in eight haul trucks, testing 24 subjects over several weeks. Each subject filled in a Fatigue Risk Questionnaire on lifestyle and health. Operators worked a 14-night, one day off, 13-day roster of 12-hour shifts in a fly-in/fly-out operation with excellent opportunities for restorative sleep between shifts. A total of 3500 hours of real-time data was collected, representing the first set of objective, real-time driver performance data for Australian mining. The data showed that for a single night of driving haul trucks, there appears to be no effect on operator fatigue from the amount of time on task (for the 12 hours). In fact performance was worse through the first eight hours than the last four. The circadian influence had a stronger affect than working more than eight hours. Of the 14 nights worked at the site, nights 13, 14, seven and two respectively, were the worst. This presents a conundrum for policy makers who may like to place caps on working hours or rosters in the hope that it will alleviate the fatigue issue. It will not. The major finding within this study is the combined influence of circadian rhythms (human body clock) and individual variability on performance. The lifestyle habits and the health of individuals have a profound effect on operator performance as shown by the strong positive correlation between high fatigue risk scores from the Fatigue Risk Questionnaire and poor performance. An individualistic approach would appear to have the best chance of reducing high potential incidents due to fatigue through successive nightshifts.

Jan 1, 2005

By H Lemos, E Nunes, D Jacobson, R Costa, L Ono, A Alves, H Delboni Jr

Oversize rock breaking and metal tramp removal are key issues for reducing primary crusher downtime, as well as improving the safety associated with its operation. Remote operation of such tasks would thus not only increase productivity, but also reduce the risks related to work in confined spaces, fall risks, and overhead hazards. These issues are particularly relevant in high-capacity operations such as iron ore mining, where large machines are in continuous operation. This article describes the architecture, construction and advanced testing of a novel remotely operated robotic mechanism for assessment and removal of metal tramp from primary crusher chambers. The system essentially includes a robotic-arm equipped with a hydraulic clamp tool for handling oversize material, as well as an oxy-flame module for cutting metal pieces entrapped within the primary crusher cavity. The first industrial unit was delivered to a large iron ore mine in Brazil, where the installation and testing is scheduled within the coming months.

Nov 8, 2021

By Quilliam B, Richmond G

Aberfoyle Ltd. has utilised a variety of flotation technologies in the Hellyer concentrator in North-Western Tasmania. Hellyer ore, with its slow flotation rates and low rate differentials between values and gangue, requires the use of long residence times and low air consumption rates in the flotation circuit. The operation of the flotation circuit, with a nominal residence time of 7 hours, has necessitated the development of a control system to provide continuity through operator shift changes. Cell selections at Hellyer varied from the 54 m3 hybrid Dorf Oliver / Maxwell (DO/MX) cells, to smaller 32 m3 Maxwell cells, conventional Don-Oliver 300 (8.5 m3) and 600 (17 m3) trough cells, and a column cell. The advantages of the large cells included low specific power consumptions and a low capital cost. However, problems with mixing and the maintenance of consistent froth depth have been identified in the hybrid DO/MX cells. Short circuiting in the trough cells was apparent, causing a considerable reduction in metallurgical performance. The column cell performs to expectation, although the application is not ideal.

Jan 1, 1991

The precious metallogenic belt and its geoloqical-tectonic location in eastern China.The precious metallogenic belt of eastern China is located in the western part of the Pacific gold metallogenic belt, and occurs in the upper levels of the continent cut by a deep fault structure tending NNE and NE, and active during the Mesozoic. The precious metallogenic period ranges mainly from Late Jurassic to Early Cretaceous (160 Ma-110 Ma); subordinate mineralisation occurred during the Hercynian period, and was rare in the proterozoic.Seven precious metallogenic belts are recognised from east to west, i.e. from continent to the margin active belts, as follows:1. Au-Ag-Te metallogenic belt of East Shandong Province2. Au-Ag-Pb-Zn metallogenic belt of west Liaoning-Miyun area3. Au-Os-Ir-Cr-Cu Mo metallogenic belt of Chengde Pingquan area4. Au-Ag-Pb-Zn metallogenic belt of Zhang Xuan area5. Au-Ag-Pb-Zn metallogenic belt of Zhejiang province6. Au-Ag-Se metallogenic belt of East Qinling area7. Au-Pd-Cu-Mo metallogenic belt of Wansu area

Jan 1, 1990

There are many different challenges when sampling mineral commodities. Sampling is part of many decision-making processes, from control of the number of drops of a reagent to all aspects involved in determining how much to pay for a mineral consignment. However, if all decisions must be supported by correct assumptions, or at least agreed terms, how can this be guaranteed? The main approach is to emphasise the importance of continuous surveying of sampling practices. If they are based on non-recommended protocols, this raises concerns. In addition, safety failures and lack of appropriate behaviour from the technical perspective can lead to disasters, both from the human and business perspectives. Impacts on safety and health are clearly unacceptable. It should be noted that imperfect safety and health practices in sampling operations have a strange correlation with incorrect sampling techniques. The commercial interface can also be affected. Companies have studied extensively the various aspects of measuring quality parameters for mineral commodities to understand the risks for investors and owners, and they take decisions that fundamentally respect the interests of parties in contracts and not result in losses. Every result should be obtained in defensible ways, and neither losses nor profits taken in indefensible ways. Most of such situations are related to bias; a significant systematic difference between a measured value and a reference value for a contractual quality parameter. Bias is always undesirable, because it always implies an incorrect advantage for one party and without doubt an undesired disadvantage for the other party. These situations are solved financially through a third-party arbitrator becoming involved in delicate situations, such as a commercial claim, but the outcome is always tangibly or intangibly bad for one of the parties. Another possibility is a permanent or temporary loss of precision. Poor precision, due its nature, generates reasonably balanced losses and profits, but it may hide out-of-control situations, generate instability and induce financial losses due to actions taken towards clearing commercial disputes involving interlaboratory programs, sample exchanges and duplicated sampling and sample preparation procedures, in the end wasting time and resources and creating a permanent source of commercial tension. While bias situations demand immediate adjustments for correctness, poor precision has to be understood as something that cannot be just calibrated out and is a situation that demands investment of time and effort. Precision optimisation has to take into account best practice for obtaining the required precision as well as cost/benefit analysis studies. Purchasers, engineers, salesmen and all personnel need to recognise that sampling is a major area to understand when taking decisions. The aim is to spread concepts that can really help, such as simple in-house actions to improve productivity and completion of surveys on commercial sampling operations, in order to ensure correct results are obtained and assertively take corrective actions, thereby establishing a healthy relationship with investors, suppliers and purchasers and in the process optimising the business.

Jan 1, 2008

By P Marianelli, J Theiler, B Beamish, A Spillman

The presence of reactive pyrite in waste rock contributes to the hazard of spontaneous combustion in emplacement facilities as it acts as an initiator of self-heating at low ambient temperatures. Organic carbon also present in the waste rocks acts as a fuel at elevated temperatures above 120°C and can lead to thermal runaway resulting in eventual ignition. A new laboratory test method (adiabatic incubation testing) is now available that can identify the presence of reactive pyrite and quantify the self-heating behaviour of the waste rock. McArthur River Mine has a waste rock profile that contains pyritic shale units, which have created spontaneous combustion events in the past. A systematic sampling and testing program is underway to characterise the spontaneous combustion hazard likelihood of the McArthur River Mine waste rocks to provide a sound database for future mine planning of the waste removal and emplacement. This paper presents some initial outcomes of this program and shows the leading practice in spontaneous combustion hazard assessment and management that has been adopted at McArthur River.CITATION:Beamish, B, Marianelli, P, Theiler, J and Spillman, A, 2018. Spontaneous combustion hazard assessment of McArthur River Mine waste rock, in Proceedings Mine Waste and Tailings Stewardship Conference 2018, pp 422–426 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 23, 2018

By Rolfe PR, Ellis BA, Clements RJ

Associated Minerals Consolidated Limited (AMC) is constructing a 112,500 tonne/yr synthetic rutile plant at Narngulu, near Geraldton in Western Australia. Design of the plant is based on the technology developed by AMC and utilised in its two existing plants at Capel in Western Australia. Ilmenite Feedstock for the plant will be sourced from AMC's mine at Eneabba and coal obtained from the Collie deposits. The plant is scheduled to come on stream in the second quarter of calendar 1987. The rationale of the decision to construct the Narngulu plant is examined against the background of the world market for high-Ti02 content feedstocks. Also provided is a detailed description of the plant and an examination of the technology used in process Design.

Jan 1, 1986

By A G. Guinea

If you were reading this article in a newspaper or similar in the 1800s, you would know that the world was firmly in the grip of the Industrial Revolution. You might have been one of the families that decided that an agriculturally based existence was no longer for you, and that the promise of a factory job was more appealing and more secure. And it was. Financially at least. Not so much from a workplace safety perspective.

May 5, 2022