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By B Hartmann

In 2003, Independence Group NL purchased the Long Shaft Nickel Mine complex (Long) in Kambalda, Western Australia. Lightning Nickel, the nickel operating arm of Independence Group, faced considerable challenges operating the mine, with the most significant challenge being able to prove that the remnant ore at Long and the associated orebodies could be mined safely and efficiently. Given the seismic history at Long, the magnitude of these challenges could not be underestimated. In an effort to achieve 100 per cent extraction of the flatter orebodies, traditional methods such as room and pillar were dismissed. A method consisting of transverse sills, butting into each other was proposed. To stop fill material from the first sill rilling into the adjoining sill, it was proposed to backfill the sills with pumped cement fill. The capital cost of the fill plant was estimated to be in excess of $1.5 million and the cost for cement alone was $1.0 million per annum. Shotcrete was already an extremely useful tool in dealing with the widely variable stress environment, but was to be used in an innovative manner that would enable the full extraction of a tabular section of the Victor South orebody. A layer of shotcrete, approximately 100 mm thick, was to be sprayed on the up dip wall of the initial development sill. The sill was to be backfilled with ænormalÆ development waste and ætoppedÆ with sand backfill. The next sill, ie slightly up dip and alongside, was to be mined along the shotcrete boundary wall. With respect to wall stability, the premise was that the shotcrete wall would stay in place and prevent the backfill (development waste and sand) from rilling into the adjoining development. It was also proposed that any breaches of the shotcrete wall would be repaired using shotcrete before substantial inflow of backfill into the ænewÆ development. This paper describes the development and implementation of this mining method, as well as some of the associated financial aspects.

Jan 1, 2008

By J Garritsen, P F. Wells, M Xu

IncoÆs Clarabelle mill currently processes ores from eight mines in the Sudbury basin area in Ontario, Canada. The ore from the Garson mine contains a much higher concentration of arsenic than the other ores. Adding this ore into the feed to the mill has resulted in an increase in arsenic content of the Cu-Ni bulk concentrate to a level that significantly affects the smelter operation, and more importantly the efficiency of Cu-Ni separation in the Matte separation plant. The arsenic occurs mainly as gersdorffite (NiAsS), with a small amount being in the form of cobaltite (CoAsS). Extensive laboratory tests on depressing arsenic in Garson ore flotation have been conducted and two reagent suites have been identified as effective arsenic depressants. One is the so called MAA depressant which is a mixture of magnesium chloride, ammonium chloride, and ammonium hydroxide. This reagent combination was reported to depress other arsenide minerals such as arsenopyrite (FeAsS) and enargite (Cu3AsS4). However, in this study for the first time it has been shown to have a depressing effect on gersdorffite. The other reagent suite, a mixture of triethylenetetramine (TETA) and sodium sulfite, that has been reported as an effective pyrrhotite (Fe1-xS) depressant in pentlandite ((NiFe)9S8) flotation, has not been reported as gersdorffite depressant before. The effectiveness of both reagent suites is more pronounced when the arsenic minerals are oxidised through pulp aeration or the addition of hydrogen peroxide. With a flow sheet consisting of a magnetic separation, rougher- scavenger flotation, followed by regrinding and cleaning of combined magnetic and scavenger concentrate, the arsenic recovery to the final Cu-Ni bulk concentrate was reduced from 73 per cent in baseline test to less than 30 per cent with either reagent suite at no decrease in nickel recovery. The TETA/sulfite reagent combination has the advantage over the MAA suite in that pyrrhotite is also depressed, rather than being activated, and the copper and nickel concentrate grades are therefore increased.

Jan 1, 2005

By Laird CH

Large quantities of brown coal are excava ted from open cut mines in the Latrobe Valley to fire the base load thermal power stations of the Victorian Electricity System. Most of the coal is removed using bucketwheel excavators which have been modified or specially designed for the conditions encountered. The actual digging efficiency of the bucketwheel excavator is strongly influenced by such factors as wheel speed, slewing speed and tooth design and arrangement. The coal deposit, although not difficult to work, is not uniform and the operation of the machine is influenced by the stability re- quirements of the excavation face.

Jan 1, 1978

The development of the lower Hunter Valley, centred around Newcastle and its suburbs is closely linked to the mining of coal and the settlements which grew to house the colliery officials, the miners and their families. The Port of Newcastle expanded and developed as a port exporting coal to many ports of the world ranging from Hawaii and Brazil to Japan and Korea. The coal which passed through the Port of Newcastle, depend- ing on the historical period in question may have been mined in Newcastle itself, or one of the nearby colliery townships such as Lambton, Wallsend, Charlestown or Hamilton, or from one of the estuarine collieries located at Carrington or Stockton or from the West Wallsend area or from East Greta, Pelaw Main or Cess- nock located on the South Maitland (Greta) coal field or from the open cut and underground mines of the Singleton Coal District.

Jan 1, 1988

Detailed petrographic analyses of coal seams from the Newcastle, Illawarra, and Lithgow Coal Measures were made for a number of localities for each of twelve seams. From these analyses characteristic standardprofiles were derived for each seam. Two broad types of profile were found; one in which vitrite-poor and vitrite-rich layers alternate, and another in which there is a steady decrease in vitrite from the base to the top of the seam. From comparison of the petrographic profiles it was concluded that the Great Northern Seam in the Northern Coalfield is a possible equivalent to the BulIi in the Southern; and likewise the Fassifern to the Balgowni...

Jan 1, 1967

By Churchill M

One of the significant changes which has occurred in the flotation sector of the minerals industry, over the last two decades, has been the successful development of the very large flotation machine. The last twenty years has seen the volume of the individual cell, available to the industry, increase by a factor of ten. Today, new mills, and existing mill modernization plans, can consider individual cell volumes as large as 85 m3 with the certainty that the metallurgical performance capability of the large machine is inherently as efficient as the smaller machine. The large flotation cell offers benefits to the user such as reduced floor space, lower total power, process control simplification, and reduced maintenance. However, the flotation machine size selection process, based on overall installation economics, must include such factors as process tonnage, flotation kinetics characteristics, and metallurgical performance objectives. This paper discusses the flotation machine size and circuit arrangement selection based on both metallurgical performance and economic considerations. A computer based flotation kinetic analysis technique, which has proven valuable in quantifying the metallurgical response of flotation circuits having different cell sizes and number, is utilized to illustrate the selection of cell size and arrangement best suited to a client's Requirement.

Jan 1, 1991

The mineralogy of regolith material for which whole rock geochemistry has already been done can be used to better understand/rank the significance of geochemical anomalies. Case studies show that the secondary minerals of the regolith environment have quite different capacities to incorporate pathfinder and target elements, eg hematite appears to be a better host to Pb than goethite and Pb rich alunite-jarosite minerals are a better Ag host than mimetite. Thus correlations between elements in regolith material may be strongly affected by mineralogy. Understanding of the significance of a geochemical anomaly is frequently enhanced by knowledge of the weathering susceptibility of different minerals. For example, when a mineralogical sequence which does not correspond to the expected order is found (eg feldspar overlying weathered material without feldspars) it is possible that transported material is present in the profile. Such mineralogical information is particularly relevant as exploration continues into areas of thick regolith.

Jan 1, 1997

By Lu S, Jiang Y

The conventional transportation system in open pit, a to u.* itc:,~> truck., to carry the ore along the ramps. Normally, the transportation distance increases greatly as mining progresses deeper. A new approach to overcome the above disadvantage is to adopt a buried roadway by which ores is transported by conveyors from the mining area to the outside dump in the shortest distance so that the production efficiency is greatly increased. Maintenance of the buried roadway in a good working condition is the key factor that determines the success or failure of the proposed approach. This includes the determination of support load, types and structures of support and other related supporting measures. The crucial problem here is to effectively control the load applied on the buried roadway in a certain range that the ordinary support can stand. Based on the theoretical analysis, numerical modelling and physical simulation testing using equivalent material, this paper studies effects on control of the support load by adopting certain measures, for instance reinforcing the surrounding rock and placing the extendable layer between the support and a rock mass. Furthermore, the influence of the dynamic load induced by the movement of heavy vehicles on the stability of the buried roadway is also investigated.

Jan 1, 1995

By M E. Webb

Safety is a key value in most leading mining companies. Despite years of effort, and significant expense in ‘programs’, operating sites seem to have been left with no real improvement in either the elimination of fatalities or sustained reduction in injuries.Safety systems and processes have grown and evolved, often to the point where they have become overly complicated and marginally useful.MMG Limited, following the consolidation of its Australian operations under a single management structure, undertook a program to effect real and sustained change in its approach to managing safety. The program aimed at improving safety by better engaging its workforce and by making safety processes simple, useful and effective. It defined the role of the supervisor in creating safe work, the role of the people doing work and the role of safe work methods.A safety diagnostic tool was developed to assess site against safety-critical mindsets, behaviours, cultures and systems. The outcome of the diagnostic is considered by the organisation to be the true lead indicator of safety performance.While still a work-in-progress, the program at the Australian Operations of MMG Limited shows that challenging common paradigms in safety management can create real change in safety performance.CITATION:Webb, M E, 2016. Making safety simple, useful and effective, in Proceedings International Mine Management Conference, pp 217-223 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 22, 2016

By S D. Dessureault

In large coal strip mines, there are many different processes at work: stripping, overburden removal using trucks/shovels, cast blasting, slot dozer pushing, more fragmentation and further truck/shovel benches. A key component to each of these steps is the use of machines. In modern operations, most machine costs are tracked within Enterprise systems that transact costs and repair work order management. Similarly, in contemporary mines most machines are tracked using technology that provides precise performance measures for each key process. Such technologies include productivity monitors on draglines, dozers and drills and fleet management systems for trucks and shovels. Linking these two sources of seemingly disparate data û costs and performance by machine û would allow for the precise calculation of unit costs by specific machine. This is similar to an activity-based costing system, except in this machine-based system, calculations are made at an even finer granular level. There are many uses for such an integrated information system in mine planning and performance management, both in real-time and through historical analysis.A real-time fleet costs (FLC) measurement process was developed as part of a larger blending-related, multi-million dollar project centred on a centralised remote control room developed at the University of ArizonaÆs Mining Information Systems and Operations Management Mine Control Center. The FLC component of the overall blending system would allow a mine controller to manage the equipment fleet by viewing its cost in real time and, when mixed with other revenue-related components, the exact profit. For example, a mine controller may show high utilisation while still maintaining a production surplus. This could occur, for example, if the equipment is driven long distances. This might appear in traditional performance metrics as æhigh production performanceÆ, but in reality may prove less profitable. This paper discusses the technical development of the FLC, its deployment and its impact on controller performance, and compares mine profitability before and after its application.

Sep 26, 2011

By Willis G. M

Preliminary experiments have shown that, when used in a fusedchloride electrolyte, titanium carbide anodes dissolve yielding lower titanium chlorides which nlay be electrolysed in situ to produce a cathode deposit of pure titanium metal. The anode residues are easily withdrawn from the cell. Further experiments have established the operating conditions for maximum efficiency in the process.The process is essentially two-stage, viz.: (1) titanium carbide production, (2) electrolysis producing metal. Power requirements appear to be moderate and this fact, combine·d with the simplicity of the process make it attractive as a possible method for the production of titanium.INTRODUCTIONDue to the high reactivity of titanium and its, affinity for oxygen and nitrogen, the extraction of this metal generally involves the use of halide. compounds as intermediates. For instance, magnesium reduction of titanium tetrachloride is the basis of the well established Kroll process and electrolysis of the lower chlorides in a molten salt bath has been proposed by Cordner and Worner (1951, p. 358) and others (Brenner and Senderoff, 1952, 223C; The TitaI Company (Inc.), 1952) as means of production of the metal. Thedifficulty of preparation of these compounds prompted a search for an alternative extraction process. The fact that aluminium, an equally reactive metal, has been prepared by electrolysis using aluminium alloy anodes suggested the possibility of a similar process for titanium production.The Titan Company (Inc.) (1952) has patented the use of crude titanium metal anode, but it was thought possible that a metallic compound, such as the carbide, could be used for this purpose. Although Lorenz and Kaufler (1909) suggested the use of carbide anodes for metal production, no...

Jan 1, 1956

By C Fountain

It is commonly known that copper smelter terms include penalties if the concentrations of elements, such as arsenic, mercury and fluorine, exceed stipulated limits. It is less commonly known that the behaviour of these elements in the smelters can depend on the processes used to treat the concentrate. The principle behind the penalties is to compensate the smelters and refineries for additional costs caused by the presence of the penalty elements, but these costs will vary depending on the process used and the location of the smelter.The issues caused by the minor elements include effects on the occupational health of smelter workers, increased environmental disposal costs, increased operating costs and reduced cathode copper quality.The effects of minor elements can be surprising. High levels of arsenic in concentrate are considered undesirable, but some smelters add arsenic to anode copper to improve the performance of the refinery.Excess concentrations of some elements will result in rejection of concentrates by smelters. China has blanket import bans on copper concentrates with concentrations of lead, arsenic cadmium, fluorine and mercury exceeding specified levels.This paper will review the behaviour of minor elements in smelters and refineries, explaining the deleterious effects of each of them, to provide a greater understanding for people and organisations wishing to market copper concentrates.CITATION:Fountain, C, 2013. The whys and wherefores of penalty elements in copper concentrates, in Proceedings MetPlant 2013 , pp 502-518 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 15, 2013

By C Sylvestre

For the last 50 years, traditional safety management has improved safety performance by: • Fixing the environment (eliminating the hazard). • Improving the system (more/less rules, procedures etc). • Making safety more conscious (more/better interactions about the importance of safety). Although these approaches certainly have merit, and may be part of an overall solution, they are not enough to prevent many modern-day incidents. Today, these three approaches are used more than before, and are used better than ever before. Yet, workplace fatalities in Australia have stagnated from 2013 to 2019, as have the number of incidents, even serious ones. In the USA, workplace fatalities have increased by 15 per cent in the same period.

May 5, 2022

By Van Nostrand J

The resettlement and relocation program that is being carried out at Gold Fields Ghana's (GFG's) Tarkwa Mine is currently the largest of its kind in Ghana, and West Africa as a whole. While such projects have been initiated previously in Ghana, in connection with the development of the Volta River Dam, Tema, and a number of other smaller resource development projects, they were not subject to the statutory requirements of Ghana's relatively new Environmental Protection Agency (EPA). Nor were they subjected to the kind of global scrutiny that is now being applied to such projects by international agencies like the World Bank. This is a result of the international community's criticism of major energy projects like the Three Gonges Dam in China and a number of similar hydro-electric projects in Southern Asia. It has meant that for this project the expectations are considerably more challenging then they have been in the past.

Jan 1, 1997

The law relating to the Treaty of Waitangi is developing rapidly at present. A number of separate, but related, developments can be identified.

Jan 1, 1988

By Robbilliard K. R, Floyd J. M

The problems facing the metallurgical industry from the viewpoint of the range of unacceptable residues, flue dusts and slags currently produced from the electrolytic zinc process, electric arc furnace scrap treatment, and blast furnace operation in lead smelting and the Imperial Smelting Process (ISP) are addressed. The application of the Ausmelt technology is discussed and analysed for the pyrometallurgical treatment of zinc plant residues, steel plant flue dusts and lead blast furnace and ISP slags, as well as the more complex issue of smelter modernisation to avoid production of zinc plant residues in the future. Processes developed from pilot work are described and indications of the economics of treatment of electrolytic zinc plant neutral residue and jarosite are given.

Jan 1, 1993

By Lawrie D. C

Finely ground beryl was decomposed by mixing with ground limestone and soda ash and heating at 900°C for 4-6 hr. The sintered mater:al was then crushed and leached by boiling under reflux with 5N sulphuric acid for up to 4 hr. The liquor containing Be, AI, Fe and other elements as sulphates, was separated from the residue which consisted mainly of silica and gypsum, either by filtration or bydecantation washing.The clarified leach liquor was first treated to remove Fe+++ by contacting with a primary amine-kerosene solution in 2 countercurrent stages. The iron free liquor was then passed to a 4-stage counter-current extraction unit where it was contacted with O·5M di- (2 ethyl hexyl) phosphoric acid (EHPA) in kerosene. Under the operating conditions, 99 per cent of the Be and 7 per cent of the Al was extracted.The Be and Al were stripped from the organic phase by sodium hydroxide solution of suitable concentration to form soluble "beryllate" and "aluminate" respectively. Most of the Be was subsequently precipitatedas Be(OH)2 by heating the alkaline solution to 90°C, the Al remaining in solution. After filtration and washing, the Be(OH)2 could be ignited directly to BeO at about 1000°C or used as a feed to further purification stages if required.A small counter-current extraction unit was operated continuously using liquor derived from the sintering and leaching stages. Dataobtained in batch laboratory tests were confirmed. A product obtained by ignition of the washed "beryllate" precipitate contained more than 99 per cent BeO.INTRODUCTIONIn 1958 an investigation was commenced into the recovery of beryllium oxide from beryl, as part of a programme to utilize mineral resources of South Australia. A survey of the literature indicated that little work had been done on direct solvent extraction of beryllium from aqueous liquors, so it was decided to apply the experience gained in this field in uranium processing to the current problem.Preliminary extraction tests on solutions of beryllium...

Jan 1, 1965

By H Dehghan Jan Abadi, K Shahriar

The iron ore district of Gol-e-Gohar (GEG) is located 60 km south-west of the city of Sirjan, in the Kerman Province of the Islamic Republic of Iran. Six exploration targets have been identified and iron ore has been mined from one area with dry and wet concentrate products sold. Prior to mining commencing in 1999, the proven reserves were estimated at 265 million tonnes (Mt) in 2004 and 40 Mt of 100 Mt overburden has since been mined. Of the six exploration targets, the largest anomaly in the GEG district is Deposit No 3. This paper discusses economic considerations focusing on mine extraction and construction of a concentration and pelletising plant to process ore from Deposit No 3 of GEG. Planned capacity of 10 Mt product (concentrate and pellet) per year is targeted to commence in 2011, and nominal capacity by 2014. The economical evaluation and analysis is one of the most important stages in the feasibility study of mine development. Financial calculations including the provision of financial resources, operation period revenue, loss and profit statement, cash flow, net cash flow, internal rate of return and net present value have been undertaken as part of the feasibility study. The feasibility study operating plan assumes a large open pit mine containing proven reserves of approximately 250 Mt. The feasibility study assumed an economic return of $80 per tonne iron pellet. The economic study determined that Deposit No 3 of GEG can be economically developed by open pit mining followed by magnetite separation and flotation to generate iron concentrate and pellets.

Jan 1, 2007

By G N. Phillips

No new goldfields have been found in the Witwatersrand Basin for over 60 years, and one consequence of this is a long-term decline in gold production. Exploration throughout this period has been based on the placer model that infers alluvial transport of gold grains and then sedimentary sorting in the basin; however, there is no viable source for so much alluvial gold and no single sedimentary setting that hosts the gold.An alternative genetic model can now provide a quantified explanation for the source of the gold, and it does not rely on alluvial gold processes. The hydrothermal model can easily explain the source of the Witwatersrand gold as being derived from the background gold at parts per billion (ppb) level throughout the Kaapvaal craton of South Africa. This gold is involved in metamorphic processes, available for solution in metamorphic fluids, and hence may be transported whilst dissolved in fluid into the Witwatersrand Basin. The hydrothermal model warrants consideration as it can explain the source of gold, the large alteration halo in the goldfields, the mineralogy, and especially the gold-carbon association.Working on the premise that if one model (placer) is not giving the desired results (discovery of new goldfields), then it may be prudent to consider alternatives. Application of a hydrothermal model to guide exploration would place importance on large and small early structures in and around the Witwatersrand Basin; it would also emphasise the geochemical nature of potential host rocks (especially C and Fe) rather than their sedimentary origin.CITATION:Phillips, G N, 2013. Origin of Witwatersrand Gold - a viable source region and source process for gold, in Proceedings World Gold 2013 , pp 175-180 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 26, 2013

By Wu Y, Qu Q

The Central Coal Mining Research Institute has developed the MAE acoustic emission monitoring system, the BD4-1 portable acoustic emission monitor and the MRB rock burst monitoring system. In the MAE system there is an IBM-PLAT, a receiver and 16 channels and the investigating range is 100 m. The main functions are detecting acoustic events from the working faces, periodically making statistics, prints, displays and storing of the results, and performing the off-line process such as drawing the curves of acoustic activity. The BD4-1 instrument has four channels, it works for more than 24 hours continuously, and keeps the data for more than 30 days after power tum-off. The BD4-1 is suited to the monitoring for a long or a short time as a fixed point where the system is invalid, especially to the monitoring of the acoustic activity promoted by the blasting. There is an IBM-PC/AT, a receiver and 16 channels spread 10 km in the system MRB. The system could on-line collect microseismic events throughout the whole mine, calculate the source location and the energy, and off-line draw the seismic activity draft of time-based or distribution in space. In practice, the forecasting is successful by using the acoustic emission and microseismic monitoring system and the portable instrument.

Jan 1, 1991