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The activiltion of sphalerite with electrolytically generated copper ions from a copper electrode instead of the usual practice of the addition of copper sulphate was studied in the laboratory. A large surface area of copper was provided by lining three sides of a bench flotation cell with copper sheeting. The lining was connected to the positive terminal of a low voltage d.c. source, and the cell impeller to the negative terminal.Sphalerite was effectively activated by this arrangement and was subsequently floated using xanthate as the collector.Flotation results comparable to those obtained with 1 lb/ton CuS04.5H20 (0,255 lb/ton copper) were obtained using 0·1062 lb/ton of electrolytic copper and 0·488 kWh of electrical energy. The wastage of copper due to the formation of insoluble precipitates was found to be dependent on the length of time the current was passed. Maximum current was passed for the shortest time to minimize wastage.

Jan 1, 1973

Over the last ten years geological and mining software products have evolved greatly. Software companies developing such products have focussed almost exclusively on the development of technical aspects of the applications, addressing geological, ore reserve estimation and mine planning problems. These specialist applications, and the many other new technologies that are being developed by a myriad of niche developers, are an essential part of todayÆs hi-tech mining operations. Technology is also being used in many other areas to improve the mining process and there is no doubt that tremendous advances are being made in all these fields. Yet there is something missing. The manner in which the technologies are used and implemented has led to the creation of many independent and inefficient æislands of technologyÆ where a variety of products from different vendors are used to address different, but related problems. Problems occur with unreliable information, data duplication, data redundancy and transferring data between applications that may be incompatible or even run on different computer platforms. These problems impede the flow and availability of information and hamper day-to-day decision-making by mine management. A solution to this problem is to take a holistic view of all the various technical applications and incorporate them into a single information technology solution. This solution must encompass all of the information requirements of a mining operation and must provide facilities that address much of the modern thinking about mine management, including strategic mine planning, value management, key performance indicators, and maintenance of a mineral balance sheet. Gemcom is developing an Integrated Resource Asset Management System (IRAMS), which is an enterprise-wide integrated computer system that encompasses various applications typically found at a mining operation. The core component of the system is a common, open, industry standard database that can be shared by many users from each of the different departments at a mine. Around that central repository are the primary applications that provide the mine with information it needs to operate. Ensuring that the information is reliable, accurate, shareable, timely and consistent will eliminate many inefficiencies, and provide significant benefits to mining companies. In turn these benefits will lead to significant improvements in decision-making, productivity and profitability for the operation. The initial version of the IRAMS system is currently being implemented at the De Beers Venetia Mine in South Africa. The system is being built around a core repository using the Microsoft æBack OfficeÆ architecture, and incorporates key technical applications from Gemcom, Whittle, De Beers Technical Team, Wenco and JKTech. The benefits of enterprise-wide systems have long been recognised in the commercial arena and enterprise resource planning (ERP) systems such as SAP, JD Edwards and MIMS are becoming commonplace in the mining industry. The more forward looking software developers and mining companies realise the need for efficient management of the information gathered during the mining process and can see that the concepts used in ERP systems apply equally to the technical applications as they did to commercial applications. The use of IT in the mining industry has expanded tremendously over the last five years as enabling technology and management acceptance has become more prevalent, and there is considerable room for dramatic growth over the next five years. The evolution of geological and mining software has now reached the stage where mines will yield the greatest returns by integrating the applications used in each area of their operations.

Jan 1, 1999

In presenting the paper, Mr. Davey quoted subsequent work which yielded k, at miscibility gap composition, of about 50.We can confirm the authors' findings for k j 300 for nearly pure tin to k 2 about 50 (average 47) from our own experience and from repeat experiments on materials described by the authors, at 1150°C.During laboratory-scale trials we also found confirmation of the authors' view that it is more difficult to reach equilibrium from the high-iron (in slag) side than from the low-iron (high-tin) side. Working from the high-iron side tends to yield results that point to a high k, leading to optimistic values of iron/tin ratio in final slags. In practice the smelting of a tin concentrate, unless it is exceptionally low in tin and high in iron, must yield initially a tin-rich slag and therefore equilibrium can only be reached from the "tinny" side.

Jan 1, 1967

By E S. Bernard

Steel fibre reinforced shotcrete (SFRS) is increasingly being used as ground support in both civil and mining applications. In recent years, methods of assessing the performance of SFRS have been developed. These include the beam test such as that prescribed by ASTM C-1018 and the panel test prescribed in the EFNARC European Shotcreting Standard. The panel test has gained popularity in recent times due to the two-way action modelled in the test. However, some difficulties have been noticed. Shear failures sometimes occur and there appears to be a rather high degree of variability in the panel test results. A new method of testing panels has been proposed. A circular panel supported on three symmetrically arranged points has been assessed at the University of Western Sydney. This paper describes the new test which may be the basis of a new specification for the testing of toughness of SFRS and summarises research work which has been carried out to-date.

Jan 1, 1999

By McConachy G. W, Wright J. V

During the 110 years since the discovery of the Broken Hill PbZnAg deposit six major mining companies have mined the ore body and explored the ore environment. Despite this activity, no new orebodies have been found at Broken Hill. The failure to discover large new resources cannot be attributed to a lack of activity because major companies have maintained substantial exploration commitments over many decades. This suggests that not only was a unique coincidence of conditions required to form the deposit but also that full recognition and definition of the critical parameters may not yet have been recognised. In an attempt to illuminate some of the more unusual and poorly studied characteristics of the ore environment some new areas of investigation are presented here which may contribute to understanding the ore deposit setting and focus exploration towards different and perhaps more productive targets. Sedimentological characteristics of the host succession of the Broken Hill deposit are apparently unique along the line of lode. An upward-coarsening megasequence reflected in the development of clastic psammites stratigraphically below the ore deposit is one important ingredient which has received little exploration focus. These psammites also host mineralisation and form part of a spectrum of quart-zrich rocks collectively referred to as gametiferous psammites, garnet quartzites and blue quartz lodes. Sedimentological data interpreted from outcrop, drill core and downhole geophysical well logs support a elastic origin for some of these rocks; an interpretation which is at variance with traditional interpretations favouring an exhalative origin. A clastic origin for many of the footwall psammites, and their close spatial association with the orebodies suggests their role in ore formation was important. It is interpreted as a critical part of the fluid flow architecture within the sedimentary basin, which focussed ore forming fluids into an unique environment favourable for trapping mineralisation. Detailed stratigraphic correlation near the deposit has also highlighted that quartzofeldspathic rocks (Potosi gneisses and lode pegmatites) have complex relationships with ore. Suites of stratabound quartzofeldspathic pegmatites have received limited study, but their distribution and voluminous development suggests they may be as important to ore formation as the psammitic lode rocks which host the orebodies. These associations are not in conflict with some recent ore forming models invoking deposition in a shallow water environments of deposition. The geochemistry of parts of the host sequence has been studied extensively in the past but this has not been merged with current stratigraphic subdivisions. A large drillhole data base now permits the geochemistry to be related to the sedimentary succession and reveals that a signature involving stratigraphic vectors best illustrated by changes in MnO, Na2O, Pb and Zn can be detected. This is interpreted to reflect sedimentary basin processes as opposed to a classical volcanic hydrothermal alteration pipe associated with seafloor venting. The stratigraphic setting together with characteristics of some of these poorly understood areas is discussed to emphasise that construction of sound models for exploration requires the total ore environment to be studied with attention directed to the geometry and setting of the full range of host rocks. Control of the greater portion of the line of lode by a single company, Pasminco Australia Limited, now permits disparate datasets and observations to be merged and presents new opportunities and encouragement for model refinement and exploration success.

Jan 1, 1993

By R J. Wood

Raise drilling (or raise boring) is not a new technology or methodology. The first raise drilling machine was developed by The Robbins Company (TRC) of the USA in 1962. TRC manufactured the first tunnel boring machine (TBM) in 1952 and Jim Robbins, the founder of the company wanted to ‘turn the TBM concept on its head’ so to speak.Many improvements have ensued in the 50 years since the first machine. Such improvements include advances in the drill rod and thread design, cutters and reaming heads. Raise boring would not have been possible without the development of the tungsten carbide insert cutters and there have been big advances in both the carbide technology and in the mechanical design of the cutters.Over time mines have developed deeper with a greater use of diesel equipment resulting in greater ventilation requirements. This in turn means larger and deeper ventilation shafts. There have also been improvements in directional drilling techniques. This all combines with the need and ability to construct larger shafts using the safe method of raise drilling. With suitable geotechnical conditions the RBR900VF is capable of drilling shafts to a diameter and depth of greater than 8 m and 2000 m respectively. Greater diameters are possible over shorter lengths with suitable ground conditions.The RBR900VF was designed and manufactured to specifications developed by Macmahon. This machine has the greatest thrust and torque capability of any machine in the world. It enables cutters to be more heavily loaded in the larger diameter heads and this is essential for efficient rock excavation. Additional features of the new machine include minimal manual handling to provide a safer working environment and higher strength steel for the drill rods providing additional safety margin.CITATION:Wood, R J, 2014. A revolution in raise boring – the development of the RBR900VF, in Proceedings 12th AusIMM Underground Operators’ Conference 2014 , pp 171–178 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Mar 24, 2014

The Goldfields extend from Norseman in the Eastern Goldfields to Marble Bar in the Pilbara; a distance of approximately 1,500 km. (Figure 1). Tailings dams are conspicuous on the relatively flat and featureless Goldfields' landscape. They impound wastes from mining and processing operations. Tailings dams interact dynamically with their environment and progressively consolidate as water is removed. Water recovery systems have been used over the last decade to improve water conservation, increase dam stability and to extend the service life of the dam. Without water recovery, dams would need to be significantly larger to permit the tailings to dry back sufficiently to support subsequent depositions. The paper reviews inter-relationships between the tailings dam and its environment and discusses water recovery systems, that are commonly used. The effectiveness of water management is illustrated by reference to seasonal water recoveries measured by Western Mining Corporation (W.M.C.) at their number 2 dam at Kambalda.

Jan 1, 1988

Forty years ago Dr Pierre M Gy, a metallurgist, introduced variography as applied to monitoring a process. Consequently, his followers used the variogram to elaborate meaningful process control charts, especially since 1993. The name æChronostatisticsÆ was suggested several times by Gy as a logical name for this new science. The intent was to draw a parallel between the variogram identifying the variability components affecting a process parameter as a function of time, and the variogram used in geostatistics identifying the variability components of a given mineral content as a function of space. Heterogeneity problems encountered have indeed strong similarities. However, there is a fundamental difference. The variogram used in geostatistics is often stationary within a given type of mineralisation. While investigating a dynamic process through Chronostatistics, there is no such thing as a stationary variogram. Still, the evolving variogram provides essential information about subtle, often overlooked process difficulties. Chronostatistics is especially useful for management to take advantage of existing data that are often a forgotten source of valuable information to pinpoint recurring structural problems. The superiority of Chronostatistics over conventional statistical process control approaches is that it links observations to the inherent heterogeneity of materials under investigation, therefore to the sampling theory. Chronostatistics is like opening a new world to the metallurgist, making the process variability speak in a more comprehensive and in-depth way. Several case studies are presented to demonstrate the potency of this new science. For each of them, observations lead to solutions for continuous process improvement, therefore attractive economic opportunities. The philosophy is this: if a control chart shows a process is out of control, it must also suggest logical and pragmatic directions for solutions. The intent of this presentation is to vastly expand on these valuable, almost forgotten ideas.

Jan 1, 2006

With the recent wider introduction of friction hoists of the Koepe type. for winding from depths of more than 3000 feet it has been found that failure by fatigue is the most common form of rope deterioration. Large numbers of wire breaks occur near the centre of the rope cross-section and it is difficult to detect these with certainty using the preferred d.c. magnetic test. For best results with conventional search coils their dimen- sions should be related to the typical wire break field pattern surrounding the longitudionally magnetised rope. The field of a broken wire was experimentally determined, using a Polish type MD6 Defectograph wire rope testing magnet and a short prepared length of rope with a movable simulated broken wire. The external field distortion perpendicular to the rope was measured by means of a gaussmeter and Hall probe. The advantages of this method are that terrestial magnetism and inherent rope "noise" have no effect on the results.

Jan 1, 1971

By Sudharto RT

Sulphides of Cu, Pb, and Zn occur in quartz veins associated with a quartz monzodiorite stock at Gunung Limbung, West Java. The mineralization was polyphase and occurred at depths of less than lkm. Wall- rock alteration is extensive and typically consists of an outer zone of propylitization and an inner zone of potassic (K-feldspar- rich) alteration. Sporadic argillic altera- tion is probably of supergene origin. A variety of elements were mobilised during hydrothermal alteration and Ba in particular shows mared enrichments in the potassic zone. Fluid inclusions in the vein quartz indicate that temperatures of mineralization were within the range 250-3900C and that two fluids with differing chemistry were involved. One fluid had high Ca/Na ratios and a low overall salinity, the other had low Ca/Na ratios and a moderate salinity. The former is probably of meteoric derivation, whilst the latter had a magmatic origin. Precipitation of the sulphides was probably brought about by mixing of these fluids.

Jan 1, 1987

By S Russell

The completion of the $1.1 B Cape Lambert Upgrade project is the second ‘pillar’ in Rio Tinto Iron Ore’s expansion program that has enabled Rio Tinto Iron Ore to effectively double iron ore shipping capacity from the Pilbara between 2003 and 2009 to 220 million tonnes per annum (Mt/a), following the successful completion of the Dampier Port upgrade project two years earlier.The Cape Lambert Upgrade has built on and enhanced many of the engineering achievements of the Dampier Port upgrade project, as well as developing innovative and unique engineering solutions for this complex ‘brownfields’ project that presented its own challenges, particularly in this distinctive open-water port environment.The project was implemented in two phases to achieve an increase in port shipping capacity from 55 to 80 Mt/a – an enhancement phase and an expansion phase.The initial enhancement phase, which provided an increase to shipping capacity from 55 to 60 Mt/a, focused on increasing the utilisation and effi ciency of existing plant and equipment with a relatively small capital expenditure.The expansion phase, which provided the increase in shipping capacity to 80 Mt/a, included extending the existing iron ore wharf by 256 m to create four shipping berths, a new shiploader, an expanded stockyard (including a new fourth bucket wheel reclaimer) and a new surge bin facility to maximise outloading tonnage rates.The Cape Lambert Upgrade project was implemented whilst the port remained fully operational and continued to ship record tonnages of iron ore throughout the project duration. This achievement required signifi cant upfront planning and sequencing of construction activities to support the operation of the port. Innovative design and construction techniques were used to mitigate the impact and enable construction activities in and around the operating plant.Throughout the project, new benchmarks in engineering design and construction practices were established, which have since been adopted for new iron ore port facilities currently in planning phases.

Jul 11, 2011

By J Aitchison, G Clarke

A reappraisal of the stratigraphy, new regional kinematic analysis and thermobarometric data allow a new interpretation of the metamorphic zoning and tectonic structure of the Upper Eocene high-pressure metamorphic core complex of northernNew Caledonia allow a three steps evolution to be proposed: 1. subduction and understacking of previously thinned continental crust elements; 2. subduction blocking due to the crustal thickening; and 3. crustal thinning and extensional detachment during the diapir-like uplift and unroofing of the eclogitic core. Steps 2 and 3 may be partly contemporaneous. Such a model accounts for the thermobarometric and radiochronologic data, and also for the weakness of substratum deformation during the emplacement of the ophiolitic nappe

Jan 1, 1995

By Perry JH, King RL

The Bureau of Mines in cooperation with Kaiser Steel Corporation conducted two methane drainage studies in an advancing section of the Sunnyside No. I Mine where production was being severely hampered by methane emissions. A total of six horizontal aoreholes were completed during the studies to an average length of 291 meters. Total gas production from the boreholes as of December 1981 has exceeded 6,088,800 m3. Methane emissions into the section were reduced by 40 pct as a result of the first drainage system. The second drainage system is currently producing 11,328 m3/day from four Doreholes. Mining of the section and cementing of the horizontal horeholes is expected to begin within 2 Years.

Jan 1, 1982

By Hodkinson I, Slight M

Over the last five years Mt Leyshon has matured into a sizeable gold mine by Australian Standards. In the later part of 1990, after commissioning of the 3.5 mtpa CIP Plant upgrade, experience indicated there was potentially additional Mill capacity beyond that being utilised at the 3.5 mtpa rate. Overall throughput was limited by crushing plant performance and high operating costs resulting from the age and condition of the main crushing plant.In addition, mining was being carried out using a mining contractor who utilised relatively small, high cost mining equipment, and on-going exploration success was also indicating that the then current mine plan would result in only a portion of the available resource being exploited.

Jan 1, 1992

The Illawarra Branch of the Australasian Institute of Mining and Metallurgy over recent years has established an enviable reputation for organising and conducting conferences, colloquia and symposia. And this Symposium must surely enhance that reputation. The subject of the Symposium, Seam Gas Drainage has become a matter of great import- ance to the Australian Coal Industry in a comparatively short time. Our short experience being due to our operations, until recent times anyway, not being unduly affected by gas. The Australian Industry, by virtue of its mines getting deeper and higher rates of extraction being required is now encountering the difficulties with gas which have for so long been part of the coal mining scene in many other countries. Because these gas emissions affect our working conditions by way of creating hazards and affect our production by way of bringing about cessation of operations from time to time this Symposium must be regarded as being very timely out here. I must congratulate the Branch Committee on the general set,yp :o.f the programme of papers. The classification of papers into four groups and the sequence in which the papers were presented provided an excellent flow through from introduction to finality. It is not my intention to further discuss individual papers - already they have been well discussed in this forum and as I understand it outside in the early hours of the morning,

Jan 1, 1982

By R T. A MacGillivray, S B. Curtis

Bacteriophage (phage) are viruses that infect bacteria. Protein coatings on the surface of the phage particle can be genetically engineered so that they bind to inorganic molecules. The filamentous phage particle is about 930 nanometres in length and 6.5 nanometres in diameter and consists of a single-stranded molecule of DNA surrounded by five different coat protein molecules denoted P3, P6, P7, P8 and P9. Peptide sequences in the P3 coat protein that bind to sphalerite and chalcopyrite have been identified. The binding is selective; phage with specific P3 peptide sequences bind to minerals but do not bind to silica or to pyrite. Two peptide sequences in the P8 coat protein that bind selectively to chalcopyrite and pyrite have also been identified. The amino acids in the P8 binding sequences are hydrophilic and thus a coating of a mineral particle with phage having these peptide sequences may render the particle hydrophilic. Experiments are underway to confirm this. Phage are relatively easy to grow and are not living organisms requiring an energy source to maintain life. Phage can also tolerate a range of pH and temperatures. Given this, and the ability to indentify phage coat proteins that bind selectively to a variety of inorganic molecules, phage have the potential to be useful tools in mineral processing and waste treatment.

Jan 1, 2008

Employing gravity recovery for coarsely liberated gold and sulfide ores has potential to lead to a signifi cant reduction in the energy required for comminution and ultimately can have a significant impact on gold processing. Most of the recognised metallurgical tools at our disposal currently have been designed around recovery of relatively finely ground minerals. In order to change the paradigm of fine grind for liberation, a new set of tools need to be recognised that are capable of separations in the coarser size fractions. Some of these tools already exist and some need to be developed but the key is the way in which the fl ow sheets are arranged. A very strong understanding is required in the existing tools and their capabilities before these new flow sheets can be optimised. Only when we understand the existing gaps in technology can we start to fill these positions with new candidates. Many ores when crushed liberate their gold bearing minerals at coarser sizes than current practice would suggest (Figure 1). In order to characterise this response in ores it is necessary to utilise some new techniques in the lab such as gravity separation and ore sorting at the sizes greater than 15 mm followed by gravity recovery on fractions from 15 mm down to 150 ¦m. The most difficult range has been the mid-sized fraction from 4.0 mm down to around 150 ¦m. This is the size range in which many ores show economic liberation starting to occur and coincidentally this is the range in which many commonly used metallurgical processes reach their operational limits due to physical constraints. Examples of these processes are flotation, hydrocyclones and whole ore leach in agitated tanks which are currently the mainstays of the processing fraternity. This is an ABSTRACT ONLY. No paper was prepared for this presentation.

Aug 1, 2010

By T Alexieva

Since the early 1900s the geotechnical community has investigated every significant failure of a tailings dam, improved our knowledge of the behaviour of the tailings storage facilities, developed analysis methods, compiled lessons learned, and committed to zero failures. The rate of occurrence of tailings dam failures has reduced since the 1980s, however, failures continue to occur and continue to surprise us. At BHP, we have decided to take an approach to the tailings management that is similar to the approach to safety. We are looking at ways to eliminate, substitute, separate or engineer around the hazard (tailings dam failure). As such, our ultimate long term goal would be to eliminate the need for new tailings facilities. Unfortunately, we have not developed yet technologies for extracting many of the common metals and minerals without producing tailings. Our shorter term goal is to substitute the current conventional slurry tailings facilities with less risky dryer facilities. We are working with vendors and research organizations to develop technologies that can be efficiently applied on a large scale. At the same time, we are committed to using the best available engineering to reduce the risks associated with our existing and new conventional tailings facilities. The best engineering can be achieved by people with the appropriate education, experience, attention to detail, discipline and authority. We have implemented a system of governance to make sure, we have the best engineering applied to all our facilities, considering the specific conditions at each site.This paper presents the current tailings governance process at BHP, and the initiatives that were undertook towards achieving a zero failure goal. CITATION:Alexieva, T, 2018. Tailings governance, in Proceedings Mine Waste and Tailings Stewardship Conference 2018, pp 2–7 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 23, 2018

By M Chiquito, R Castedo, P Segarra, L M. López, J A. Sanchidrián, J Navarro

The aim of this work is to assess the performance of different constructive solutions against explosions on the strength of masonry walls. The solutions tested, namely an external metal mesh, a glass fibre film on the external face of the wall and a basalt fibre film located on the inner face of the wall, have low to medium cost and are originally designed for other purposes, like seismic protection. Four cubic boxes 3 × 3 × 3 m were built using each of the solutions and typical masonry blocks. In the tests, a spherical plastic explosive initiated in the centre was placed at scaled distance of 2.9 m/kg1/3, so that moderate damage would be caused on the wall. In order to assess the performance of the explosive, pressure gauges were placed at the wall and at different distances from the explosion. Additionally, vibrations were monitored with seismographs in the far field and a high-speed camera was used to estimate the shock wave velocity during the tests. The resulting damage has been evaluated on 13 points of the external wall of each box using a rebound hammer. Damage maps have been drawn for each wall based on these measurements and damage has been assessed inside the box considering the fragments mass launched during the test. The use of external metal mess leads to a decrease of 34 per cent on damage of the external wall and 38 per cent reduction of spalling. The use of a film in the inner wall provides a strong reduction on spalling.CITATION:López, L M, Segarra, P, Castedo, R, Sanchidrián, J A, Navarro, J, Santos, A P and Chiquito, M, 2015. Performance of different constructive solutions against explosions in full-scale masonry walls, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 819–824 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By R Fleming, G Jones

An ocean outfall is currently under construction in Christchurch, New Zealand to transfer treated wastewater from the existing treatment ponds at the city wastewater treatment plant to diffusers located 3 km offshore. The New Zealand $85 million project comprises a new pump station and 5 km of 1800 mm diameter pipeline with a design capacity of 6.0 cumecs. The pipeline comprises 2.3 km of concrete pipe installed by microtunnelling and 2.7 km of polyethene marine pipe installed by dredge and lay. This paper describes the consent process, key environmental and community constraints, the tender process, risk provisions included in the contract, the type of contract, partnering provisions, geotechnical design issues and the pipejacking construction activities and issues.

Jan 1, 2008