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By Rath M. C, Das R. P

Studies were carried out on dissolution and oxidation of iron powder in ammonia-ammonium carbonate solution using oxygen over pressures. Cobalt and nickel losses during iron oxidation under different conditions were investigated. Regression equations were derived for percent cobalt loss and percent iron oxidation using ammonia, ammonium carbonate and oxygen partial pressure as the variables. The equations were tested for adequacy using Fisher's test. Cobalt losses increased with the increase of initial cobalt concentration and about 400 mg/l of cobalt was lost from a solution containing 500 mg/l cobalt. A maximum of about 80 mg/l nickel was lost from 1 g/l nickel containing solution, and this loss remained the same even when the nickel concentration was increased to 7.5 g/l.

Jan 1, 1992

By Lawson F

Synthetic calaverite (Au Tez) has been prepared and its physical properties checked.Simple flotation tests indicate that the recovery of calaverite should be possible using n-butyl or sec-butyl xanthate collectors under approximately pi I neutral conditions with a copper sulphate activator.Roasting calaverite in air at moderate temperatures resulted in its decomposition with the formation of elemental gold and tellurium dioxide.In alkaline oxygenated cyanide solutions, both gold and tellurium tend to dissolve. At pHs less than 14, about 50 per cent of the tellurium remains as elemental tellurium; however in very strongly alkaline solutions, essentially all of the tellurium is converted to the soluble tellurite ion (TeOl-).However, even at high pHs, the solubility of gold in the cyanide solution is still low due almost certainly to passivation effects.

Jan 1, 1991

By R Symes

The Fosterville Goldmine in Victoria Australia employs the BIOX« Process to liberate gold from its sulfidic flotation concentrate through bacterial oxidation. Gold occurrence is primarily as submicron particles in pyrite and arsenopyrite and has been described as being in æsolid solutionÆ and therefore not amenable to direct cyanidation. Once liberated by the oxidation process, the gold is then available for cyanide leaching. During the oxidation process it has been found that a portion of the liberated gold becomes suspended in the liquid phase in what appears to be a colloidal state. This liquid becomes a waste stream during washing of the oxidised solids and the suspended gold is therefore lost. A method was previously developed using an addition of quebracho tannin to significantly reduce this loss by formation of an iron-tannin precipitate which captures the gold which then reports to the cyanide leach circuit with the oxidised concentrate solids onto which it is adsorbed.This paper discusses the development and plant trial of a second processing step to further enhance gold recovery by use of flotation tailings essentially as a source of extra surface area to capture residual tannin-iron precipitate and its associated gold not recovered in the first step.CITATION:Symes, R, 2012. Recovery of colloidal gold from oxidised concentrate wash liquor - Further improvement, in Proceedings 11th AusIMM Mill OperatorsÆ Conference, pp 383-388 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 29, 2012

The Golden Plateau Mine is located at Cracow in central Queensland, 350 kilometres north west of Brisbane. The mine was operated by Golden Plateau NL as an underground mine from 1933 to 1976 with a total production of 18.5 tonnes of gold. Prod

Jan 1, 1994

Woodlawn Mines began underground operations in 1986. At the time of going underground it was envisaged that there would be no 'contract' payment to the underground employees. This was a relatively unique step to make, especially as most major underground mines in Australia relied heavily on the contract system to motivate their workforce. (Obviously with varying degrees of success.) Woodlawn faced the task of motivating their employees through a multi-skilled system with a great emphasis on leadership and a genuine care for their employees. The 'proof of the pudding' is that Woodlawn has not lost any time over industrial issues since beginning underground operations in 1986. To achieve success in any operation the organisation must not only be advanced in its management principles but also be prepared to be innovative in the way it deals with physical problems, ie ground control, equipment selection and maintenance. Difficult ground conditions at Woodlawn have necessitated the deployment of two Cabolt Jumbos and the construction of cost-effective shotcrete systems. The shotcrete system now being built has been tested in a prototype form and is proving to be a safe and simple way to manage weak, low stress friable ground. Although the ground at Woodlawn has low stress component by virtue of the fact the ore can have a density of 4.5dm3, cable dowelling has become a necessity. The two cable dowel jumbos install high quality reinforced cables. The pressure of 'production' means that these machines must be consistently available for use and the training of maintenance personnel and operators ensures that a maximum of cable dowels can be installed over any given time span. In any modem mine ventilation is a primary concern and the major area of concern comes from the vehicles themselves. In our recent replacement for the standard 'Toro' loader, three engine options were considered. A relative newcomer to underground mining was accepted. The Detroit 60 series (DDEC) engine came with a great reputation and has lived up to this. The engine has an electronic management system that reduces particulates to a hardly visible minimum, provides great amounts of engine power and reduces fuel consumption by approximately 45 per cent. The operational benefits of such an engine are worth sharing through this conference.

Jan 1, 1995

By Zhen Y. Y, Cook A, Jell J. S, Fleming P. J G

Remapping of the Burdekin Basin has resulted in subdivision of the three interfingering basin-wide megafacies previously recognised in the Early to Middle Devonian Fanning River Group. Eleven carbonate and siliciclastic facies are now identified within the three megafacies, representing coastal plain, shoreline, nearshore, and shallow marine shelf depositional environments. The facies reflect two phases of a major transgression. An initial phase, in the Early Devonian, was confined to the far north of the basin, whereas a second, main phase, resulted in the encroachment of the sea from the east or southeast in the Middle Devonian.The proposed depositional model begins with the drowning of a coastal plain and the transgression of shoreline and nearshore facies between granitic and metamorphic headlands and/or islands. This was followed by the deposition of a patch reef and fringing reef complex including stromatoporoid and coral bioherms, biostromes, and oncolitic, crinoidal, and brachiopod-dominated banks/shoals, together with foreslopes and submarine channels, carbonate rubble deposits and terrigenous sediments. Sedimentation during the peak of the transgression was dominated by sheltered carbonate shelf facies, the maximum, flooding surface being recognisable across most of the Burdekin Basin. Progradation of muddy and sandy nearshore bay and shoreline facies soon followed, terminating carbonate deposition.

Jan 1, 1990

By P Ottenio, B CarrT

In the last 40 years, the froth flotation process widely spread in the paper industry becoming the dominant technology for ink removal from recovered paper slurries and cellulose fibres recovery. Most of current models used to describe the flotation deinking process are based on hydrodynamic and statistical theories of ink particles collision/attachment to air bubbles. The complexity of these theoretical models, together with the variability of the recovered papers composition, does not allow to define a set of æeasy to handleÆ equations to be used for modelling industrial flotation cells. This main limiting aspect makes that, in several deinking process modelling tools, basic parameters used to characterise the flotation unit, ie yield, ink removal efficiency, water loss, are constant parameters. Although in some process simulation tools the flotation yield/efficiency is adapted to process control parameters (air ratio, pulp flow, pulp consistency), physicochemical variables (namely the pulp frothing aptitude, the pulp surface tension and the ink adhesion energy to air bubbles) are not taken into account to adjust the flotation yield/efficiency. Data collected during recent laboratory and pilot plant experiments focusing on the role of surface active substances on the flotation efficiency were therefore interpreted and used to identify general trends that could be described with simple semi-empirical models. A set of model equations using surface tension and froth removal height as main variables was then defined in order to describe the behaviour of a pilot flotation cell. Trends obtained during the dynamic simulation of the deinking pilot plant were in good agreement with experimental data obtained under similar experimental conditions, thus indicating that developed equations can forecast with good approximation the behaviour of a flotation deinking unit.

Jan 1, 2005

By Hoberg H, Schneider FU

Flotation tests were conducted with galena, quartz and with synthetic mixtures of the two, in different ranges of grain size, and with different process parameter variants. Physico-chemical analyses were also carried out on surface energy and on xanthate adsorption on galena with different grain sizes. Reference will also be made to hydrodynamics, interfacial chemistry and the influence exerted by grain size in flotation.

Jan 1, 1993

The long-term production schedule of open pit mines that maximises the net present value (NPV) of a given project relies on the proper design of phases (pushbacks) within the ultimate pit limits. There is not a phase design algorithm applied in the mining industry today that gives yearly production schedules that are optimum.The majority of phase design algorithms currently in use by the mining industry aims at grouping the blocks that fall within the ultimate pit limits into phases such that the average value of the blocks within each phase decrease as the size of the phases increase. Current phase design methods are typically based on a pit limit optimisation algorithm, originally introduced by Lerchs and Grossmann (LG) in 1965. To obtain multiple pit shells to be used for the phase design, the LG pit limit algorithm successively applied to economic block models by changing the price of the commodity or some other factor that properly parameterises the size of the pit. These modified economic block models are developed by predetermining the destination for each block in the model based on a breakeven analysis and highest economic outcome between alternative destinations. Phase designs determined by these existing algorithms may be suboptimal if a given project utilises multiple processing facilities for metal recovery and particularly if these facilities have restrictions (constraints) that require blending of attributes in the feed. To overcome these problems in obtaining phases that optimise overall production schedules, a new algorithm is developed at the Colorado School of Mines. The algorithm determines the phases of an open pit mine by taking into account multiple process options for the blocks and period by period blending requirements. This algorithm has been implemented within a software program (the software) and is being prototyped successfully in the design of improved pushbacks at a copper mine in South America and on a gold mine in Nevada. This presentation will demonstrate the shortcomings of the traditional phase design methodologies based on comparison of results coming from the new approach versus the traditional.

Dec 6, 2010

By M Bilodeau, G Caro, R Beaudoin, D Labrie

In 2005, Dyno Nobel Canada Inc, DynoConsult and CANMET-MMSL used their pool of expertise in blasting, ground control, open pit and underground mining, mineral processing, information technology and applied mineralogy to launch a research project aimed at evaluating the role of electronic detonators in the development of a sustainable energy-efficient rock reduction process. The overall objectives were to improve health and safety in a mining environment and reduce energy consumption and greenhouse gas (GHG) production in the Canadian mining industry. The study was conducted in a quarry located in Nova Scotia, Canada, with the objective of taking advantage of the higher accuracy and flexibility of electronic detonators towards improving blast efficiency and measuring its impact on productivity in a quarry environment and energy savings. Optimising the blast sequence was the first aspect to be considered before starting to look at designing bigger blasts and achieving productivity improvements, without creating additional environmental concerns, as the quarryÆs location was representing a challenge in itself in the surrounding community. The use of high-speed cameras (500 fps) was an improved means of analysing blast dynamics during the firing sequence. Seismic monitoring and linear superposition techniques were also applied to validate the sequences to be tested in all three specific geological areas. The combination of field measurements allowed to identify the optimal blasting sequences that would then be delivered accurately with the electronic initiation systems. The data from 12 blasts (six with electronic detonators and six with pyrotechnic detonators) carried out in three different geological formations (soft, medium and hard rock) showed that the electronic blasting technology could increase rock fragmentation by 15 to 20 per cent. A more uniform distribution of rock fragment size was also obtained. Blast improvements on downstream processes resulted in a five per cent productivity increase in rock excavation and transportation, a ten per cent energy reduction in primary crushing and a 15 per cent increase in the primary crusher throughput. A prototype soft-sensor based on primary crusher data (eg energy consumption, throughput, feed and product size distribution) and a simplified computer process model were developed for online measurement of a rock operating work index. Furthermore, rock samples were collected and specimens were prepared in order to determine the tensile and compressive strength of the rock materials, evaluate the aggregate crushing work index and examine the development of micro and macro-fractures under binocular and scanning electron microscopy (SEM). Blast-induced rock damage was evaluated at the end of the laboratory testing program. A reduction in rock hardness by about 30 per cent was observed after blasting. However, the impact of the blasting method (eg using electronic versus pyrotechnic detonators) on the induced rock damage was either absent or not perceptible within the measurement technique accuracy and the number of samples analysed.

Jan 1, 2007

There is an increasing demand for refrigeration as mines progress deeper. Mine refrigeration plants have special requirements in terms of their duty and application. There are no national or international standards applicable for the testing of these plants. There have been numerous examples of plants failing to meet their required nominal capacity, but with the plant owner being unable to enforce the design duty on the manufacturer, due to a failure to unambiguously specify testing or accepting criteria. This paper discusses some of the reasons for performance shortcomings and describes a methodology for developing and specifying performance criteria, when inviting design and/or construction tenders, and a method of performance and acceptance testing once the plant has been built and commissioned. These guidelines encompass the full range of performance duties expected from a mine plant, including stable operation at maximum and minimum plant capacity, and under the various combinations of extremes of high and low condensing and evaporating pressures. A description of a methodology for developing a computer-based mine refrigeration plant model is also presented as part of the performance testing criteria. The methodology is illustrated with reference to the actual performance and acceptance testing process used on the worldÆs largest bulk air cooler (R67) at the Enterprise mine at Mount Isa, Australia.

Jan 1, 2005

By P York

The study commenced in October 2012, to understand the basic ecology of the spotted-tailed quoll (Dasyurus maculatus) and to confirm whether the species utilise previously mined land on the Mt Owen mine site that was rehabilitated in 1996 to 2011, as part of their home range. The spotted-tailed quoll is a widely distributed marsupial carnivore that is listed as rare or threatened in every state in which it occurs. The species is a forest-dependent marsupial carnivore that occupies a wide range of habitat types (Long and Nelson, 2004).The first part of the study involved trapping a spotted-tailed quoll and fitting the individual with a combined global positioning system / ultra high frequency (GPS/UHF) radio-transmitter collar (Telemetry Solution – Quantum 4000E). The benefit of the GPS/UHF collar is that it records locations (or fixes) at intervals programmed by the user. The UHF component allows the researcher to locate the individual at a frequent interval, and the Quantum 4000E also has a remote download function, enabling the GPS data stored in the collar to be wirelessly transmitted between the collar and researcher. The benefit of this new technology is that the animal does not need to be repeatedly captured to retrieve the GPS data.Daytime searches are also undertaken using the UHF receiver to locate the individual and locations of daytime denning and latrine sites. The location of each den site is recorded using a hand-held GPS. Data downloaded from the GPS collar is then imported and mapped using computer software program ARCGIS (geographic information system), to overlay the data points onto aerial photography.Results demonstrate that threatened species will utilise rehabilitation areas post mining. The data presented will be used to develop a greater understanding of threatened species ecology in and around rehabilitated areas, which will assist in the planning and design of native forest rehabilitation areas.CITATION:York, P, 2014. Mt Owen Mine spotted-tailed quoll study, in Proceedings Life-of-Mine 2014 , pp 591–596 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

By García B., Wolff E.

In Colombia, northeast of Antioquia, there is a gold deposit that has produced continuously since the middle of the XIX century, located within mining title RPP-140, property of Gran Colombia Gold Segovia (GCGS) since 2010. Mining materials are taken to the “María Dama” Processing Plant where 1500 tonnes of materials are processed daily. Before 2010, the previous owner of the mining title processed about 600 tpd and directly discharged almost all tailings, given that they had no capacity to put them into final deposits. El Chocho was conceived as a final tailings deposit to store the pulp produced by the processing plant; it was divided into two phases with two dams (upper dam and lower dam) given that the presence of illegal miners at the lower phase impeded a single dam design. A squatter impeded construction of the upper dam; so afterwards, starting at the higher end was necessary (owned by GCGS), building dam 1B to store tailings in pulp; after the squatter returned the lands to the owner (GCGS), construction of tailings dam 1A was required and thus complete construction of dam 1C or the upper dam. While all of this was happening, GCGS decided to acquire a 1500 tpd filter press which currently dehydrates tailings in order to take them to the valley controlled by dam 1A. Construction of dam 1A was designed following the containment wall model, made with geotextile tubes. These improvements generated reduced pressure on renewable natural resources because water is recirculated and less fresh water contributions are required; less pressure is placed on soil, flora and fauna because the area intervened for tailings storage will have a higher storage capacity and, as such, a longer useful life.

Jun 17, 2024

By Mallett C

Coal mines are dynamic systems that change continually in size, shape, and condition. Large quantities of data about production, coal quality, ground stability, ventilation monitoring, equipment performance and location, vehicle and personnel movements and geology, are generated from all parts of the mine.Internet technology and virtual reality technology are now being combined to provide an intuitive, multi-dimensional information system which can simultaneously display any information that can be collected and stored by a computer. Physical information is directly displayed as 3-dimensional objects in the mine model. Numerical and text information is dynamically linked to these objects and accessed by "clicking" on them.

Jan 1, 1998

By Y Durkheim, P Saunier, L Ameglio

"In the last decade Afitex developed the Draintube™ geocomposite, which provides simultaneous drainage and waterproofing functions. This new type of drain tubes planar geocomposites (DTPG) differs from other geocomposites as the drainage core is composed of multiple corrugated and perforated pipes instead of biaxial or triaxial nets. It is furthermore associated with needle-punch stitched layers of non-woven geotextiles, which act either as capillary mediums or as filters.In this paper, the structure of the Draintube™ drainage composite is presented along with its key properties and the drainage mechanism associated with its particular structure.The relevance of this kind of structure is then reviewed based on past and current laboratory bench evaluations and field installations for mining applications such as the covering of acid rock drainage (ARD) tailings for the Central Manitoba Mine (Canada) site-rehabilitation; and as a pregnant solution collection layer in heap leach pads.Some of the demonstrated critical advantages of Draintube™ in the mining industry are as follows: reduction of the thickness, hence lower volume of granular drain layers improvement of fluid and gas collection and reduction of the hydraulic load reduction of secondary collector network mechanical protection of the sealing membrane fast and economical installation of interlifts stability under extreme conditions (compression, temperature, pH) increased stability of entire covering system and reinforcement of protection of dykes filtration of the covered material customised drainage positive connection of the geocomposite to collector pipes enable leaks detection (using a conductive textile layer) with an electrical test.CITATION:Saunier, P, Ameglio, L and Durkheim, Y, 2015. Tubular drainage and lining geocomposite for mine tailings and heap leach pads, in Proceedings Tailings and Mine Waste Management for the 21st Century, pp 297–304 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jul 27, 2015

By J J. Campbell, G J. Wilkie

The ores of the Golden Mile exhibit considerable complexity. As a consequence, the operating company, Kalgoorlie Consolidated Gold Mines (KCGM), considered it important to develop a coherent database of information describing the nature of the many ore lodes in terms of (1) rock properties and mineralogical content, including relative proportions, grain size, associations and deportment of key elements between minerals, (2) the relative behaviour of consituent minerals in various stages of processing and (3) the nature of the final products and key intermediate streams. The paper describes a sequence of metallurgical tests covering comminution, flotation, gravity concentration, leaching and calcining, carried out on three lodes of the Golden Mile. Key samples generated by the testing were subjected to comprehensive size-by-elemental assaying and QEM*SEM mineralogical determinations of sulphide and precious metal associations. Significant differences between lodes were identified, and the impact of these differences on processing is discussed.

Jan 1, 1998

By Bacigalupo-Rose

Simulations of complex physical phenomena, such as hurricanes and fluid flow around space vehicles, can now be effectively explored using modem visualisation techniques which have been developed to examine the results of numerical modelling using supercomputers. These techniques are also being applied extensively in medical investigations, including viewing the interior of the human brain. We have now applied these same techniques to the visualisation of gold deposits.Grade control in open pit gold mining operations may involve the collection of at least half a million samples in each mine. Extensive drilling programs also accompany the early reserve evaluation stages and exploration in advance of mining. Maximum utilisation of these very large amounts of information requires an ability to integrate, examine and present large three-dimensional data sets in order to be able to derive and effectively communicate information on grade distribution and geological controls.

Jan 1, 1993

By A Whaanga

The use of photogrammetry has greatly increased the accuracy of 3D mapping underground. However, this has not reduced the need or desire for geologists to produce plans and sections showing an interpretation of the mapped geology. At the Waihi Underground Gold Mine, a hybrid solution has been developed that utilises the accuracy of photogrammetry and mapping onto face photos with the CAD-based Deswik.MappingTM functions to create plan and section maps. These have the benefit of looking like traditional paper maps but are more spatially accurate and richly attributed with metadata that can be filtered and exported to downstream processes. Deswik.MappingTM is a tablet-based solution that allows the geologist to map digitally with a stylus. Automation is utilised for the updating of survey as-builts, approved designs, drill holes, geological mapping, vein interpretations and mine work areas, reducing the requirement to print out maps at various locations and scales. Having 3D mine software on a tablet device provides a wealth of features not available when using paper: scaling is a problem of the past; information can be turned on and off; features can be viewed in 3D; and measurements between points of interest can be calculated in 3D space, for example, between vein wireframes and drill hole sample information. A suite of custom scripts has been developed that take the spatially accurate, registered and attributed polyline data from photogrammetry scans and converts them to a geological mapping legend with vein textures, structural information, and lithological boundaries. These 3D maps can be plotted in plan or section view and satisfy the requirements of the most ardent paper map supporter.

Mar 22, 2022

By M Breen

In 2009, George Fisher mine began to seriously consider the transition from pyrotechnic detonators to electronic detonators. Initially, the electronic detonators were used for complex crown shots or areas where ground conditions had the potential for excessive overbreak. After critically evaluating the potential safety benefits, production increases and ability to redesign stopes to better manage a thinly bedded hanging wall, the mine decided to embrace the technology.

Nov 8, 2011

By T Zhao, K Wang, Z Zhang

Tailings pond safety monitoring is vital for preventing dam failures and ensuring environmental safety. Unmanned Aerial Vehicles (UAVs) can enhance tailings pond monitoring with flexible operational cycles and the ability to collect remote sensing data from inaccessible areas. While many mining operations have adopted UAVs for tailings pond management, their full potential in data acquisition and subsequent analytical processing remains largely untapped. This paper explores various case studies where UAVs have been utilised for monitoring key aspects of tailings ponds such as beach line indicators, dam displacement and erosion, slurry discharge processes, and tailings pond capacity. We also present examples where data derived from UAVs have been instrumental in slope stability analysis, seepage modelling, Tailings Dam Breach Analysis (TDBA), and risk prediction. By integrating UAV technology with traditional ground-based sensor techniques, this approach significantly enhances the precision and reliability of hazard prevention and management in tailings pond operations.

Sep 1, 2024