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Tyre costs constitute 20-40 per cent of the operating cost of large haulage trucks, and tyre pressure maintenance is an important factor in minimizing costs.In the past, control over the hot (built-up) pressures of earthmover tyres has been inaccurate and inconsistent because it has not been possible, in a practical way, to measure the tyre's contained air temperature.A method for measuring this contained air temperature has now been devised using a bi-metallic probe thermometer inserted through the valve stem. Using these measurements in conjunction with a pressuretemperaturechart drawn up using the general gas equation, very accurate control over hot tyre pressures is now possible.

Jan 1, 1979

By K H. Esbensen, K Engström

The conclusion from the debate over the last decade in the mining sector is that, for grade control, reverse circulation (RC) drill sampling gives more reliable results due to less sampling problems than blasthole samples. However, by conducting the latter with well-controlled procedures there still exist fair possibilities to counteract the major blasthole sampling problems and achieve fit-for-purpose representativeness, especially if based on minimal loss of fines. In the present PhD study, extensive replicate experiments and variographic characterisations are conducted to evaluate the performance of manual blasthole (BH) sampling and sectorial segment sampling. The experiments were performed in Luossavaara-Kiirunavaara AB (LKAB)’s Leveäniemi open pit mine in the north of Sweden. The experimental area is an apatite-magnetite iron ore deposit of the Kiruna type, with the demand to exhibit a maximum of local heterogeneity to allow the experiment the largest possible conclusion powers. Gathering and splitting the complete BH drill cutting cones (fines cone, coarse cone) served as an authoritative reference on which to assess the representativity of the two BH sampling methods.Results show that manual BH drill sampling is able to produce samples with an acceptable accuracy and precision if performed properly and with insight. Based on variographic comparison, segment sampling shows similar precision for chemical grades as the manual sampling, while the particle size distributions were more deviating for segment sampling than for manual sampling at the high and low size ranges. Possible reasons for these partly surprising results are discussed.For further investigation of the performance of BH versus RC drill sampling, a second experiment has been planned on a parallel profile. This will result in an unprecedented opportunity for a full variographic comparison between RC and BH sampling, aimed at designing specific, fit-for-purpose sampling procedures as a function of ore quality, cut-off grades and important contaminant levels.CITATION:Engström, K and Esbensen, K H, 2017. Blasthole sampling (replicate and variographic experiments) in LKAB open pit iron ore mines – fit-for-purpose representativity?, Australia, in Proceedings Eighth World Conference on Sampling and Blending , pp 85–96 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2017

By N Madani, N Battalgazy

Geostatistical simulation has been widely used in mineral resource classification of metalliferous deposits based on international standards such as JORC code which is one of the most extensively used around the world for reporting the mineral resources and ore reserves alongside with objectives of the companies (Sadeghi, Madani and Carranza, 2015). However, the modeling process becomes challenging whenever the relationship between the variables of interest is complicated and cumbersome to model. This characteristic sometimes manifests itself in complex spatial and global cross-correlation measures, deeply depending on the formation and genesis of the deposit. The objective then is to generate the models that not only reproduces these significant characteristics, but also, it leads to a better understanding of a mineral resource estimation and successive decision-makings. In this respect, there are different approaches taking into account the spatial correlation structures, for which can be classified as independent simulation, co-simulation, and factor-based methodologies. In this paper, three techniques: Turning Bands Independent Simulation (TBSIM), Turning Bands Co-Simulation (TBCOSIM) and Projection Pursuit Multivariate Transform (PPMT); from those aforementioned approaches are selected to model two cross-correlated variables (Iron and Aluminum Oxide) belonging to an Iron ore deposit located in Brazil, in order to examine which methodology better reproduces the corresponding complexity in terms of local correlation measure. CITATION: Battalgazy, N and Madani, N, 2018. Mineral resource assessment in complex ore deposits based on international standards, in Proceedings Complex Orebodies Conference 2018, pp 79–81 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

The increased focus on best practice environmental management has led to mining and mineral processing companies developing a variety of procedures to ensure that the environmental impacts of their operations are minimised, and that company managements are fully aware of these impacts and the policies and procedures established to ensure this process. Parallel to this, international standards for the development and implementation of environmental management systems are being promoted as necessary for companies to demonstrate their due diligence. Good environmental management systems should be built upon the systems already established within companies, and should ensure that the process of continual improvement is integral to their operation. An outline of the basic components of environmental management systems is provided, along with examples of the way various mining companies have implemented such systems. The benefits of best practice environmental management to mining companies are also considered.

Jan 1, 1995

Recycling and Recovering Fine Particles from Auto Shredding Residue (ASR/SR) to Conserve Raw Materials and Protect Environment

Sep 13, 2010

By A Roseman, T Gruber

Traditional methods for installing gaskets for segmented bored tunnels have relied upon different bonding procedures with adhesives that carry a series of disadvantages to segment producers. Fixation of the gaskets into the concrete segment as part of the casting procedure has been developed over the last 20 years and has emerged as an economical solution to produce high-quality tunnel segments for various technical tunnel applications. This paper investigates the advantages of using anchored gaskets, the different tunnel systems that employ anchor gaskets and reviews the first anchor gasket project; the Lee Tunnel and analyses how segment production efficiencies are gained.CITATION:Gruber, T and Roseman, A, 2014. Use of anchored gaskets in segmented bored tunnels, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 253–256 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By J C. Volkwein, A D. A Hansen, E Sarver, C Barrett

Ensuring that diesel particulate matter (DPM) levels in underground metal and non-metal mines are maintained below statutory limits is an essential requirement of mine ventilation systems. However, despite the cost of providing ventilation, air ventilation rates are usually based upon models, assumptions, or measurements integrated over long durations rather than actual need. Real-time measurement of DPM, interpreted in terms of mine activity schedules, can offer better ventilation management to keep DPM within regulated levels while controlling costs. This work presents data from three demonstration sites with in-mine applications of an environmental particulate sensor that measured black carbon (BC) as a surrogate for DPM.Aethalometers are a class of environmental monitors that measure the light absorbance of aerosol particles at several optical wavelengths. A model AE33 Aethalometer was operated in three separate mines for periods of two weeks, three months, and seven-plus months, and the data was reported in real time as a concentration of BC. Concentration of aromatic organic compounds, which can indicate other forms of combustion, was also reported. The data was used to:- measure the relative efficiency of a new scale-model DPM air scrubber- determine if ventilation could be reduced in a shotcrete loading facility without compromising air quality- evaluate diurnal and weekly DPM levels in a large-entry stone mine. Instrument data were displayed locally and stored for later downloading in all cases. In one mine, the instrument was connected to a local controller, and in another it was connected to the mine’s underground network so that DPM data was presented in real time to a display in the mine ventilation engineering office on the surface.The results showed that the air scrubber removes from 82 per cent to 95 per cent of the DPM; that DPM produced during shotcrete loading is only a minor part of overall DPM levels; and that wide variations in DPM levels exist in the limestone operation. The DPM monitor operated continuously for extended periods in these underground environments. The only maintenance required was the routine replacement of filter tape, typically on a two-week schedule. A sample diluter, which is currently being tested, could extend the intervals between filter changes. The real-time data output of the Aethalometer is appropriate for direct integration into ventilation-on-demand control systems.CITATION:Volkwein, J C, Barrett, C, Sarver, E and Hansen, A D A, 2017. Application of an environmental ‘black carbon’ particulate sensor for continuous measurement of DPM in three underground mines, in Proceedings Australian Mine Vent Conference 2017, pp 143–150 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

The application of cheap robust microprocessor based units to achieve monitoring and control in an underground mining environment is described. The functional layout of the programmable controller and the methods of multiplexing and processing information from local and remote sources are examined as are features for refrigeration plant control.High noise immunity communication to a remote micro computer uses existing telephone lines and enables display and print of essential data. The development of this system then leads to applications in monitoring compressed air, ore transport and underground fires.In conclusion, the problems of data presentation to different levels of management and the future philosophy of a central multi-reporting system are discussed.

Jan 1, 1985

By Grano S. R, Ralston J

It is the perennial problem most metallurgists face when examining data collected from laboratory float tests and plant surveys - there are more numbers than we know what to do with! The objective of this paper is to analyse and interpret a set

Jan 1, 1994

By A C. Edwards

The Mesozoides of North-Eastern Asia represent a collage of exotic terranes which were accreted to the margins of the Siberian continent. In the Late Precambrian and Phanerozoic, the passive margin of the Siberian continent (the current north-east) broke up into a number of discrete fragments as a result of rifting events in the Riphean, Early and Middle Paleozoic. Rift related mineralisation includes stratiform and stratabound copper and base metal mineralisation in the structures of the Omulevka, Okhotsk and Prikolyma basement terranes, as well as along the edge of the Siberian continent in the Paleozoic sediments of the Verkhoyansk passive margin. During the Late Mesozoic the terranes were reassembled in a series of accretionary events. At the end of the Jurassic, the velocity of the Kula plate increased, and the opening of the Canadian Basin in the Arctic commenced, changing the vectors along which the Siberian and North American plates moved. Island arcs terranes were pushed back onto the Omolon super-terrane which was in turn pushed onto the Siberian Craton in a series of massive collisional events that resulted in the restructuring of the whole region. Numerous granitoids characterised by collisional and island arc chemistries with Au and accompanying Sn, and W mineralisation were emplaced. Mesothermal gold-quartz mineralisation was emplaced in a series of narrow belts that adjoin major crustal sutures and that spatially overlap belts of granitoids and zones of subgreenschist metamorphism. Each of these gold-quartz vein belts corresponds with a specific collisional phase. In the middle Cretaceous, the Okhotsk-Chukotka volcanic belt developed along the paleo-Pacific margin of the Siberian continent. Epithermal Au-Ag developed in the volcanics and shallow mesothermal Au-Ag-quartz and Au-Sb mineralisation developed in the Mesozoides. Porphyry and skarn style mineralisation developed in both the island arcs and in the continental Okhotsk-Chukotka Volcanic Belt.

Jan 1, 1999

This paper is written as a supplement to that of Edwards, Baker and Knight on "The Geology of the Wonthaggi Coalfield" 1, the West Area pit being in an early developmental stage at the time of their paper. The thin seams to the west of Dudley Basin 2 had beenknown for many years but it was not until 1935 that it became necessary to work them. The West Area Pit came into production as Dudley Area Pit approached exhaustion in 1937. From available information it was estimated that early work would be in a 36in. bottom seam. The present top seam was not included in the reserves, but it was to be extracted where it proved thick enough for economical working.THE SEAMSEdwards, Baker and :Knight (1944) had insufficient information to correlate positively the West Area seams with those in the Dudley Basin. Their opinion was, however, that they were a westerly extension of the Bottom Seam. Since then the driving of the present north-east heading towards No. 4 Bench McBride Tunnel has established that the West Area seams are those worked as Bottom Seam in the Dudley Basin. West Area Top Seam is a seam that occurred above the Bottom Seam in the Dudley Basin. Only sporadic attempts have been made to work it in Central Area, because 30in. was considered an economic minimum height until recent times. This seam should not be confused with Top Seam, Dudley Basin, which lies some 300ft. above the bottom seam measures and except in isolated areas over deeper workings has been eroded away in West Area.

Jan 1, 1953

The El Pe±on gold-silver deposit comprises four epithermal, low-sulfidation veins, which contain 2.9 million oz Au and 48 million oz Ag. Provisional data on alteration mineralogy, fluid inclusions, and vein textures constrain the chemistry and hydrology of the hydrothermal system responsible for ore mineralisation at El Pe±on. Alteration minerals include quartz, adularia, albite, illite, smectite, calcite, chlorite, and pyrite. Alteration minerals suggest the existence of near neutral pH, low salinity hydrothermal fluids, which circulated over an area greater than 18 km2. Complex mineral zonation patterns result from variations in host rock permeability and composition, overprinting alteration possibly produced by thermal waters from surficial and peripheral parts of the hydrothermal system, and supergene weathering in the hyperarid environment. Upflow zones were focused along N-S and NE trending structures, producing crustiform quartz-adularia+carbonate veins. Fluid inclusion data indicate vein deposition from low salinity (

Jan 1, 2002

By D Brett

The Paper presents the authors thoughts on how the mining industry should be improving the education of site personnel so they can provide a greater level of effective control of tailings dam safety including empowerment to develop their own documentation, monitoring and surveillance systems and to better liaise with specialist external technical staff or consultants.

Jul 1, 2021

THOUGH the literature on the chamber process is considerable, it mostly refers to European conditions. Owing to the demand for acid for flotation and leaching at the mine, it may be necessary to work the process under other conditions. Consequently, some results obtained during the chlorination days at Mount Morgan, within the Tropic of Capricorn, may be useful for reference when working in a similar climate. Though the chambers must be protected against tropical storms, thorough ventilation should be provided, with plenty of space between the chambers, which are almost invariably crowded together. Not only does the space assist in the cooling of the chambers, but it is very desirable during repairs, when lead andtimber have to be hoisted up. The connecting flues between the chambers, which are fairly efficient mixers and condensers, should be round, supported from above, and with the least possible timber about them. Their position and arrangement deserve careful attention. Lattice work will be sufficient protection for the sides of the chambers, and the roof should be high and well ventilated. The Mount Morgan plant, crowded and not well situated, consisted of seven chambers (four over 50 ft. in length), one Glover tower 7 ft. 2 in sq. x 20 ft. high, one Gay Lussac 9 ft. sq. x 30 ft. higb, also one 5 ft. diam. x 25 ft. high. There was one pipe column 4: ft. sq. x 14 ft. 6 in. high. The chambers were run as one unit, and were much lower than those usually constructed in Europe-less than 15 ft. high. Provided that suitable timber can be obtained, 20 ft. is quite low enough. It should be quite satisfactory to use round poles for the studs, and so admit more air space between studs andlead.

Jan 1, 1920

CrusherMapperTM - A New Tool for Crusher Condition Monitoring The efficiency of mineral processing plants is entirely dependent on the availability of the plant equipment critical path. This typically concerns comminution circuits consisting of primary crushers and primary grinding mills. Crusher and mill availability are determined by the frequency and duration of maintenance shutdowns, which are primarily driven by the need for replacement of sacrificial liners. The change of crusher and mill liner shape over respective life cycles also strongly affects plant efficiency. It is therefore highly desirable to accurately monitor the condition of mills and crushers in order to optimise plant efficiency through maximised availability and targeted liner shape. Traditional comminution liner and other production parameter condition monitoring has been attempted through ineffective methods which prevent satisfactory management of crusher and mill maintenance and reduce operational control. This situation has recently dramatically improved for grinding mills through the development and commercial deployment of MillMapperÖ, a technology based on three-dimensional laser scanning data and dedicated software (Franke, Lichti and Stewart, 2006; Franke and Lichti, 2007; 2008; Franke, 2008; Franke, Redman, Johnson and Michalek, 2009). At the time of writing in late 2009, MillMapperÖ is in successful use at a rate of approximately 170 surveys and associated reports per annum at processing plants in Australasia, South America, North America and Africa. This paper presents the introduction of CrusherMapperÖ, the MillMapperÖ equivalent for crushers. CrusherMapperÖ also utilises high density, high accuracy laser scanning data, and features dedicated algorithms for three-dimensional monitoring of wear on crusher concaves and mantles. This facilitates the detection of wear hot spots or zones or localised liner failures, and accurate forecasting of reline tonnages and dates. It also for the first time provides the means to establish optimised concave and mantle shapes in order to achieve production targets. In contrast to any other currently utilised condition monitoring method, CrusherMapperÖ data collection can occur remotely and does not require any shutdown or crusher isolation. This method therefore does not interrupt crusher production while at the same time eliminating any confined space risk normally associated with taking measurements inside the crusher cavity.

Sep 13, 2010

By S Mitra, D O’Dea, N Barrett, S, T Honey, M M. Hoque

The steel industry is currently exploring hydrogen-enriched blast furnace operations as a means to reduce the greenhouse gas emissions. However, there is a need to investigate the gas permeability behaviour of mixed burdens comprising of lump and sinter as the current knowledge regarding their behaviour is limited, particularly with regards to hydrogen enrichment. In the present study, a series of interrupted softening and melting (S&M) under load tests were carried out in a hydrogen rich gas environment (~15 per cent) in the temperature range from 1000 to 1300°C by placing different types of ferrous ore layer including Newman Blend Lump (NBLL), sinter and sinter-NBLL mixed burden in between two coke layers. X-ray computed tomography (CT) was then used to scan the interrupted test samples. Scanned images were first analysed using an image processing workflow implemented in ImageJ and the material simulator GeoDict (v2022) to segment different phases such as coke, ferrous and void based on their grey scale values. A quantitative analysis was then performed on the segmented images to estimate the phase volume fraction as well as bed permeability. Bed void fraction thus obtained agreed well with the bed contraction data obtained from the S&M test. It was further noted that both ferrous layer void fraction and bed permeability decreased linearly with increasing temperature for all ore samples. The mixed burden voidage changed in a similar fashion to the sinter, demonstrating a high temperature interaction between the two materials

Sep 18, 2023

The title of this address was selected before I had an opportunity to consider in detail the matters that I would like to discuss. Accordingly, I chose a very broad subject-so broad indeed that it would be foolhardy for me to attempt to deal with more than a few aspects of it. I do not propose to touch. at all on the developments to date of our mining and metallurgical enterprises, beyond paying a sincere tribute'to the skill and enterprise of those who have established an international reputation for Australian mining and metallurgy. I would rather look ahead and discuss certain factors that will play a decisive part in the future development of our mineral resources. I do this in no dogmatic spirit, and I hope that my remarks may lead to discussions which will stimulate action where it is needed.In recent years my colleagues and I have been forced by circumstances to give consideration to problems in the fields of mining and geology, and in process metallurgy, which lie outside the scope of our own research work. People come to us with metallurgical problems because they know of no more appropriate place to go, and it is distressing to have to inform them that it is nobody's job to offer them advice and assistance. I want to suggest to your Institute that it should press strongly for the provision of properresearch facilities for the mining and metallurgical industries, such as aready exist in most enlightened countries. In such countries, those connected with the development of mineral resources are able to obtain information and advice from Geological Surveys, Mines Departments or Bureaux of Mines, which offer far more comprehensive services than are available in this country.Before discussing specific technical problems of the mining and minerals industries, I shall enunciate certain general principles that I believe should be followed in respect to the technical side of the development of all Australian industries. The problem can, I suggest, be considered in three parts-technical education production, and research. I shall confine my remarks mostly to the research aspect, for it is with this that I am most familiar.For the efficient development of any industry in Australia, it is essential firstly that We should learn what is going on abroad, and secondly that we should simultaneously conduct independent research. In the latter sphere the Governmeht'departments and the private companies' or groups of companies should have complementary functions, the former concentrating on problems common to a number of companies or industries, and the latter on their oWn individual problems. It is essential to the continued existence of Australian industry that both company and govern...

Jan 1, 1944

By P Holtham, K Duffy, L Pyle, W Valery

The mining industry is becoming increasingly focused on pre-concentration due to its potential economic and environmental benefits, particularly for the more complex, low-grade, high throughput operations now being developed. Advances in technology have seen bulk ore sorting (BOS) trialled at several operations. However, BOS should not be seen as a ‘silver bullet’, it can offer significant benefits, but only under the right conditions. Deposits with interspersed mineralogy or disseminated, fine-grained minerals can be difficult for BOS. Large batches of barren or low-grade material are required for BOS to be effective. Hatch has recently completed several studies for clients who believed that bulk sorting was the most suitable pre-concentration technique for their operation, based only on an assumed sorter recovery or on laboratory trials of the chosen sensor. However, minimal consideration had been given to the heterogeneity of the deposit, the achievable separation batch size or sensor repeatability. Evaluation of BOS needs to consider both heterogeneity and sensor suitability. The valuable or gangue mineral must be present in such a way that it can be separated effectively in the large bulk sorting batch sizes, without competing minerals or changing ore characteristics affecting the metal upgrade or recovery. Also, the sensor chosen must be able to detect either the valuable mineral, a proxy for the valuable mineral, or a gangue mineral for rejection with sufficient accuracy and precision (repeatability). This paper presents three recent case studies, emphasizing markers which indicated that bulk sorting was unsuitable for the project whilst highlighting the pre-concentration technologies which were applicable (including particle sorting, and coarse particle gravity separation). The modelling methodology, equipment sizing and forward work plans developed to verify these alternative solutions are also presented, demonstrating the key factors contributing to a thorough scoping assessment.

Aug 24, 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

Standard petrographic profiles for many Permian seams from New South Wales and Queensland have been drawn up. The standard profiles of seams of the same age and from one or more coalfields were used to compile an idealized or type seam sequence for those coals in which more than half the seam profiles were similar to one another. A marked similarity existed between at least 7 of the 10 type seam sequences formed.The configurations of the vitrite-plus-clarite contents of the plies of 95 per cent of the seams could be formed from different arrangements of 3 basic sequences. These were...

Jan 1, 1970