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By Qian Li, Honggui Han, Jun Wang, Shichao Yu, Chunxiao Zhao, Maoxing Hong, Rui Liao, Xingxing Wang

In this study, bioleaching experiments, synchrotron X-ray Diffraction (SR-XRD), X-ray absorption near edge structure (XANES) and X-ray Photoelectron Spectroscopy (XPS) were conducted to investigate the intermediates and surface species of bornite leached by mesophilic mixed bacteria of Leptospirillum ferriphilum, Acidithiobacillus caldus and Sulfobacillus thermosulfidooxidans. CuS, Cu9Fe9S16 and S8 were the main intermediate species during bornite bioleaching by mesophilic mixed bacteria, and CuFeS2 was also detected. The surface species of S2− and S2 2− would be polymerized to Sn 2− during bioleaching. The formation of element sulfur and the increase of its content were confirmed by the fitted results of XPS spectra. The presence of polysulfide and element sulfur did not inhibit the bornite bioleaching. The formations of CuS and CuFeS2 were confirmed by the results of Cu K-edge XANES spectra.

Mar 1, 2018

By David G. Adam

Introduction Syncrude Canada Ltd. is the operating company for a consortium of industry and government participants that produce synthetic crude oil from their leases in the Athabasca Oil Sands. Production from the $2.3 billion (1978) integrated mining, extraction, and bitumen upgrading and utility complex started in September 1978. Production is currently about 6.4 Mm3/a (40 million bbl per year) of high quality synthetic crude oil. This is done by upgrading the extracted bitumen from the oil sands mined. Plans are to increase the production to 8 Mm3/a (50 million bbl pier year) by 1989. At that time, the mining operation will be required to deliver 100 Mt/a (110 million stpy) of oil sand (ore) to the extraction plants, and handle quantities of waste ranging from 50 to 75 Mt/a (55 to 83 million stpy). The Syncrude plant is located at Mildred Lake, 40 km (25 miles) north of Fort McMurray and 480 km (300 miles) north of Edmonton, Alberta. Climate, particularly winter, is therefore a major factor affecting the design and operation of all the Syncrude production facilities. Bitumen production, consisting of overburden removal, oil/sand mining, bitumen extraction, and tailings disposal, account for about half the total SCO production costs. Considerable research and development, therefore, continues to be applied to improve both material handling and bitumen recovery methods. Potential applications for feeder breakers were identified in the material handling aspects of both overburden and oil sand mining to reduce cost and to attain planned production increments. Overburden removal Overburden materials on the leases comprise thin Pleistocene sands, gravel and fill, and sands, silts and clays of the thicker Clearwater Formation with the silt to clay components predominating. The latter contains multiple leases of hard siltstone with unconfined compressive strengths up to 148 MPa and thicknesses up 0.1 to 0.9 m (1 to 3ft). Characteristics of the overburden as well as the climatic environment and scale of operation present unique problems for the efficient removal of the material. In a bucketwheel/conveyor system, the weak silty clay formations require relatively flat working slopes for safe operation, while the siltstone lenses and frozen overburden require blasting or selective removal by other equipment. These factors, combined with the normal bucketwheel/conveyor design parameters, lead to high capital investment and relatively inefficient use of that capital. Hydraulic mining alternatives, including dredging, are constrained by severe clay settling problems in the waste disposal

Jan 6, 1986

By S. Ng, Peter Stapleton, Paul Mankowski, J. Spence, R. Siy

"Syncrude has developed a low energy extraction process for the recovery of bitumen from oil sand. This new process operates at a temperature of 25 °C, resulting in substantially lower energy costs and lower capital costs, especially for the thermal energy generation equipment. The process will be used in Syncrude’s Aurora Mine, which is scheduled for startup in mid 2000. The flowsheet for Low Energy Extraction includes hydraulic transport of oil sand slurry, and bitumen separation using collector and frother chemicals and air as process aids. A number of flow sheet innovations and optimizations have been included, resulting in the next generation of extraction technology. Experimental pilot plant results, engineering progress to date and areas of ongoing work will be discussed. SUMMARYThe Low Energy Extraction Process has been successfully developed for commercial implementation at Aurora. The 1996 100 tonne hour Field Pilot demonstrated that the bitumen recovery target could be met with an 11.1% grade oil sand. However, pilot plant bitumen recoveries for a lower grade oil sand were not acceptable. The subsequent flowsheet optimization study led to a new flowsheet for Low Energy Extraction, which includes a primary separation vessel, a flotation circuit for PSV middlings, and the use of middlings displacement in the PSV cone bottom with flotation underflow. A test program conducted in 1997 showed that the new flowsheet could significantly improve the bitumen recoveries for lower grade oil sands. Engineering work on process scale-up led to selection of a 30 meter diameter PSV, with a tangential feedwell. The successful development and commercialization of Low Energy Extraction for the Aurora Mine Project is a major enabling step in the Syncrude 21 program. The low energy requirements of this process allow Syncrude to develop the Aurora leases more cost effectively. The use of this process results in major capital cost savings, predominantly in the thermal energy infrastructure and also provides long term operating cost advantages for Syncrude."

Jan 1, 1999

The world's largest hydraulic excavator was recently introduced at Syncrude's North Mine at Fort McMurray, Alberta, in Canada. O&K's 826t (910-st) behemoth RH400, with a 42-m3 (55-cu yd) bucket, is capable of loading 72.5 t (80 st) in one pass. Syncrude's Alberta operation is the nation's largest single source of crude oil. It is also the world's largest producer of oil from oil sands. Syncrude produces 205,000 bbl/day, expects to increase production to 225,000 bbl/day by 1999 and to 320,000 bbl/day by 2005. That translates to 73.5 million bbl of Syncrude Sweet Blend (SSB) produced in 1996, 82 million bbl in 1999 and 114 million bbl in 2005. The North Mine is a new development that will replace the current East Mine, to be depleted of oil sand by the end of 1999. The North Mine will feature hydrotransport, a new and unique method of transporting oil sand from the pit to the process plant. Oil sand from the truck-and-shovel operation will be processed through a double-roll crusher and placed in a cyclofeeder where it mixes with hot water. The material is then screened and transported by pipeline to the extraction plant. Hydrotransport will replace conventional conveyor transport for moving raw product from the pit. Mine development will also use two 290-t (320-st) haul trucks to compliment the fleet of existing 218-t (240-st) trucks.

Jan 1, 1998

By B. R. List, E. R. F. Lord

The Syncrude open pit mine, located near Fort McMurray in northeastern Alberta, produces approximately 410 000 tonnes of oil sand feed daily, which, after undergoing a bitumen extraction phase, generates approximately 315000 tonnes of tailings solids daily. The tailings are used to hydraulically construct containment dykes and supporting beaches of the storage facilities. Tailings deposition commenced in May 1978 with the commissioning of the Mildred Lake Settling Basin which is currently composed of approximately 600M m3of solid sand approximately 300M m3of contained fluids with fine tailings in suspension for consolidation. Two other storage facilities, commissioned over the past six years, have been developed to store sand and consolidated fine tailings referred to as mature fine tailings. Fine tailings reduction initiatives being developed will be successful in reducing future production of fine tailings volume by 20%. These initiatives include spiking (addition of fine tailings to coarse tailings lines for deposition), composite tailings (addition of gypsum to promote consolidation) and freeze/thaw dewatering, also to promote consolidation. The mandate of research efforts is to enhance tailings disposal and to develop economical and technically feasible reclamation initiatives. Final tailings landscapes will be geotechnically stable and ecologically productive to minimize or eliminate long-term liability. This technical paper will review the design philosophies of the current facilities and provide an overview of the areas of continuous improvement in the field of tailings management practices through the concerted research efforts and their implementation.

Jan 1, 1997

By Jimsher Aneli

The investigation of some peculiarities of conductivity dependence on filler type and amount in the polymer composites has been conducted. It is established, that conductivity of composites based on phenolformaldehide resin essentially depends on proportion of double fillers: graphite + carbon black, graphite+ andesite, contained in composites. It was shown, that these composites characterized by synergetic effect ? non additive influence of fillers concentration on the conductivity of composites. Some other properties of composites contained binary fillers (effect of temperature and pressure on the conductivity) have been investigated.

Jan 1, 2006

By Markus A. Reuter

In this paper, the kinetics of phosphorous production in submerged-arc furnaces will be discussed as a function of temperature, as well as various ore and reductant types. Interesting positive synergetic effects on the rate of reaction could be observed when mixing different types of ores. The results will be discussed with reference to a kinetic model, microprobe analyses, etc. The effects these results have on the control of the furnace will also be discussed in detail, indicating how these could be incorporated into the electrode and metallurgical control systems for submerged arc-furnaces.

Jan 1, 2000

By S Farrokhpay, M Zanin

Although it is well understood that in flotation collection zone and froth zone are deeply interconnected, and reagents (and in particular collectors and frothers) cannot be selected without considering their synergistic effect, this concept is rarely applied in plant practice. The feed mineralogy also has an important role in how particles and reagents interact in flotation, which is sometimes overlooked by operators. In this work, a combination of batch flotation tests and froth stability measurements was used to optimise the collector and frother scheme for the flotation of a copper ore. The methodology was applied to an Australian copper plant which was experiencing high variability in froth stability in the roughers when the feed ore mineralogy was changing. It was hypothesised that chalcopyrite in the feed in combination with isobutyl-xanthate had a destabilising effect on the froth phase under the reagents scheme used. Froth stability was restored if a shorter chain length, less hydrophobic, xanthate was employed. It is apparent that the hydrophobicity of adsorbed films at the solid/liquid/air interfaces has a critical role in enhancing or reducing froth stability. Unstable froth causes a reduction in copper recovery in spite of a high collection zone flotation rate. The case study suggests that collection zone and froth zone can rarely be optimised independently of each other. With the laboratory procedure adopted, a more suitable reagents scheme was determined to respond to changes in the feed mineralogy, avoiding fluctuations in plant performance due to unexpected froth instability.CITATION:Farrokhpay, S and Zanin, M, 2012. Synergic effect of collector and frother on froth stability and flotation recovery - An industrial case, in Proceedings 11th AusIMM Mill OperatorsÆ Conference, pp 145-150 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 29, 2012

By Yves-Laurent Turcotte

Notre conférencier, Monsieur Yves L. Turcotte, Vice-président et Directeur général chez Promaintech Novaxa est diplômé en génie industriel de l?Université du Québec à Trois-Rivières et détient une maîtrise en gestion de projets de l?Université du Québec à Montréal. Il est une véritable sommité canadienne dans le domaine de l?amélioration de la performance des organisations. Provenant d'entreprises manufacturières et de services, il possède plus de 20 ans d?expérience en tant que développeur de technologies, conseiller et formateur auprès d?entreprises. Il a à son actif la réalisation de mandats dans plus de 400 entreprises. Il est reconnu pour sa grande capacité d?analyse et pour trouver des solutions novatrices et profitables aux problèmes des organisations les plus complexes. Aujourd'hui, il dirige Promaintech Novaxa, une division de DMR, qui a célébré son dixième anniversaire en 2006. Cette organisation ayant des places d?affaires dans la région de Montréal, Québec et Vancouver compte plus de 50 professionnels et a une carte de visite dans 16 pays. Les axes d?intervention sont le Management, la Productivité, la Fiabilité, l?Innovation et l?Amélioration Continue.

Feb 1, 2008

By J Joughin, D Kyan, L Rollin

In line with the 2015 Paris Agreement and corresponding climate disclosure requirements, many mining companies have publicly disclosed that they are developing and/or implementing ambitious decarbonisation strategies. Sometimes these strategies can be linked to the development of community programs and/or the creation of a positive legacy post-closure. Renewable power is key to most decarbonisation strategies – some mines will get this from external sources and others will establish on-site power generation and storage facilities. A range of options are available to develop renewable power generation (eg solar panel, wind farm, hydropower) and energy storage (eg battery, hydrogen, pumped hydroelectricity). Land access, impact assessments, planning and environmental approvals are required to establish new facilities. Host communities are more likely to be in favour of, or at least will accommodate, new power supply developments if these are planned with a benefit to the communities. Transitioning to renewables raises new challenges. Among these are high upfront costs and access to capital, energy demand variability, supply intermittency and variability, storage limitations, grid stability and reliability, transmission and distribution infrastructure constraints. Compounding these challenges are issues such as infrastructure resilience to extreme weather events (eg heat, wind), land use and access, lengthy permitting processes, community perceptions, skilled labour requirements, and meeting mine closure objectives. Renewable energy sources provide a more decentralised source of energy that reduces reliance on imported fuels, thereby increasing energy security and lowering production costs. On the contrary, implementing renewable energy could lead to potential negative impacts such as visual perception from the community, competitive land usage, electricity price raises due to upgrading infrastructure and the use of electricity storage capacities. As part of the definition of an environmental and social management plan, participative stakeholder engagement is required to identify benefits to the communities. For example, among the recognised benefits of developing solar panels (increase job opportunities, reduce soil erosion), various technologies have been experimented globally for the last ten years and are emerging due to their proven community benefits. Key findings to enhance those benefits can range from the development of innovative practices such as ‘agri-/aqua-voltaic’, ‘solar grazing’ to optimise land usage and stimulate the local economy (Table 1), to the implementation of technologies providing services to communities such as mobile water desalination plants or ‘smart grid’ systems to minimise energy clipping during peak-load of oversized renewable energy facilities (Table 2). While developing those synergies, careful management is required to avoid creating superfluous energy service needs from community programs. Energy sufficiency should remain a key principle according to the sufficiency, efficiency and renewable framework of the Intergovernmental Panel on Climate Change. Darby and Fawcett (2018) define energy sufficiency has ‘a state in which people’s basic needs for energy services are met equitably and ecological limits are respected’. Sufficiency tackles the causes of the environmental impacts of human activities by avoiding the demand for energy and materials over the life cycle of buildings and goods. Efficiency tackles the symptoms of the environmental impacts of human activities by improving energy and material intensities. The third pillar, renewables, tackles the consequences of the environmental impacts of human activities by reducing the carbon intensity of energy supply (Cabeza et al, 2022). Life of Mine Conference 2023 | Brisbane, Australia | 2–4 August 2023 34 This paper provides project developers, decision-makers and regulatory authorities with ideas on synergies between renewable energy options and community development programs. These can be considered to enhance stakeholders’ support for implementation of decarbonisation strategies.

Aug 2, 2023

By A. House

Newmont Mining Corporation owns and operates the Phoenix Mine near Battle Mountain, Nevada, USA. The existing milling facility has operated since 2006. Following the startup of the milling operation, and coupled with the upswing in the copper market, Newmont realized that Phoenix needed a process option to treat lowgrade transition and oxide copper ores. This meant that potentially revenue generating ore was being mined as waste. With no system in place to treat the transition and oxide copper, work began to determine the most feasible approach. After evaluating multiple options, the flow sheet was set for a run-of-mine (ROM) heap leach pad and solvent extraction/electrowinning plant (L-SX/EW). This paper will discuss the synergies and challenges of developing a copper L-SX/EW plant at the Phoenix copper-gold mill.

Jan 1, 2010

By E Widzyk-Capehart, P Vallejos, R Asenjo, J Ruiz-del-Solar

Throughout the minerals industry, it is evident that a new wave of technological innovation is needed as the mining sector looks for ways to achieve higher security and safety as well as higher production rates with less investment. Innovation has always been one of the key factors in achieving success within the mining industry. However, its importance will be especially relevant in the coming years if negative trends in commodity prices and new challenges facing the industry (lower grades, deeper mines and economy of scales) are to be overcome and the future sustainability and profitability of the sector ensured.The drive towards fully autonomous operations has begun, with the implementation of automated systems in both surface and underground operations. However, these automated systems are currently planned and realised with well-defined automated tasks within structured environments and isolated spaces. Currently, there is no interaction between automated systems, manned systems or humans, which creates physically isolated environments.For fully autonomous and continuous operations, the automated systems need to operate in environments that enable flexible interactions between automated machines, tele- and manually operated machines and humans.In this paper, we address the automation paradigm considering the synergistic collaboration between humans and automated systems. In this paradigm, humans and machines would interact in a flexible, collaborative and synergistic way without the need for isolation. The implementation of this concept within mining operations will have to be underpinned by science and technological developments and will require adaptation from many fields, including robotics, automation, distributed systems, communication, human factors, pattern recognition and mine design.The paper also presents the research and development work being undertaken at the University of Chile’s Advanced Mining Technology Center, in collaboration with the Chilean mining industry. This will provide the basis for flexible interactions between humans and technology-based systems towards a future of autonomous and continuous mining systems.CITATION:Ruiz-del-Solar, J, Widzyk-Capehart, E, Vallejos, P and Asenjo, R, 2015. Synergistic collaboration of humans and automated systems – innovative steps towards fully autonomous and continuous mining systems, in Proceedings Third International Future Mining Conference, pp 83–94 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 4, 2015

By Q Zhou, H Nordberg, W Wang-Geissler

Efficiently controlling foam/froth within mineral processing continues to pose a challenge to the mining sector. The foaming characteristics of aqueous solutions for two-phase systems of air/liquid are well-studied with theories and mechanisms proposed to describe and predict foam formation and stability. The types and structures of reagents that either promote or prevent foaming/froth formation and stability are well-defined in these studies and practiced across various applications. Three-phase systems of air/liquid/solid, such as froth from mineral slurries, however, pose a challenge with the presence of a large quantity of relatively fine mineral particles. Theories and mechanisms that rationalise the effects of chemical additives as a defoamer or foaming agent in aqueous can be applied as a general rule, but do not provide the most effective solution for mineral slurry systems. Silicone-based defoamers, particularly their O/W emulsions, have been widely and successfully used at various stages of mineral processing to efficiently control the mineral slurry foaming properties. However, their foaming control ability could be significantly impacted by different processing aids used during the upstream process. In a zinc-rich mineral system, a silicone-based defoamer starts losing the properties necessary to effectively control foaming in the leaching circuit when throughput is increased. In this study, the synergistic defoaming/anti-foaming effects from surfactants and silicone-based defoamers are discussed to effectively control foaming/froth in the zinc leaching circuit, even with lower total defoamer dosage. Improvements during mineral processing can also lead to a cleaner mineral grade by reducing waste.

Aug 24, 2022

By Rongjin Zhu, Yue Wu, Shuxing Qiu, Qingyun Zhang, Shengfu Zhang

Co-pyrolysis of biomass and coal was investigated as an effective way to reduce the greenhouse gas emission. The effects of poplar on the thermal behavior of fat coal were studied using thermogravimetric analyzer. The blended samples heated to characteristic temperature were subjected to attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) to characterize the macromolecular structure. The results indicated that the synergistic effects existed in co-pyrolysis process of blends since lower char yield than calculated values, and the synergistic effects presented positive and negative trend with the increase of temperature, respectively. The carbonyl/carboxyl C=O stretching vibration functional groups and aliphatic side chain from individual fuels were decomposed in advance during co-pyrolysis. Furthermore, the hydrocarbon-generating potential (A-factor) and thermal maturity(C-factor) of the mixtures showed nonadditivity performance.

Mar 1, 2018

By B. T. Lu, J. L. Luo, H. X. Guo

This paper investigated the synergistic effect in the slurry-erosion process of carbon steel. In line with the mechanisms of material loss, the synergism due to interaction of erosion and corrosion was divided into the corrosion enhanced by erosion and erosion enhanced by corrosion. The erosion-corrosion tests were conducted with A1045 steel in slurries containing silica sand. Experimental results showed that the rotating of the sample in corrosive media raised both OCP and corrosion rate, but the impingement of solid particles did not affect the corrosion current significantly. In the quiescent solutions, the Faraday's law gave a good prediction for the weight loss caused by corrosion but for rotating samples, the weight loss experimentally measured was virtually greater than that predicted by the Faraday's law, indicating that the corrosion-enhanced erosion could occur in corrosive fluids in absence of solid particles. A half-logarithm relationship was observed between the weight loss due to corrosion-enhanced erosion and the anodic current density.

Jan 1, 2004

By S. M. Khandrika

Most of the coal presently used by the utility industry is cleaned at preparation plants employing wet processes. While water is the mainstay of coal washing, it is one of the least desirable components in the final product causing a reduction of the heating value as well as handling difficulties. Currently available dewatering techniques are inefficient for dewatering very fine coal (minus 325 mesh). The US coal industry has expressed serious concern about utilizing advanced cleaning processes such as column flotation because an efficient and economical dewatering process is not available.

Jan 1, 1992

By F. Yang, S. S. Long

Mixed fatty acids, such as oxidised paraffin soap, are frequently used as a substitute for oleic acid in flotation of scheelite in China. Not only because it is cheaper than oleic acid, but also because it is superior in flotation performance to oleic acid. This superiority is generally attributed to the mixed fatty acids' synergistic effect. In this paper, the synergistic effect of oxidised paraffin soap was investigated. We found it mainly consists of a series of saturated fatty acid salts, with six to nineteen carbon atoms. All the contained fatty acids were classified into four groups based on their chain length to make the research work practical. Also, the groups were labelled as 1, 2, 3, and 4 in order. The research was simplified into studying the synergistic effect of four equivalent collectors, instead of fourteen fatty acids. It is justified by the fact that neighbouring fatty acids are expected to have a similar flotation performance. The synergistic effect of the four groups of fatty acids was studied by single-mineral flotation with single groups, binary mixtures, ternary mixtures, and the full component, as collector respectively. The flotation performance index and synergy value were introduced to evaluate flotation performance and synergistic effect of groups, respectively. The results show that the mixture 1+2+3 has the strongest synergy of all followed by the mixtures 1+3 and 2+3. The mixture 3+4 and 1+2, on the other hand, have negative synergy. The synergistic effect of mixtures of groups indicate that being consecutive in length and a broad range of lengths are vital for fatty acids to enhance synergy. Group 3 is fundamental for the collecting action of 733 oxidised paraffin soap in the flotation of scheelite. The fatty acid soap in group 4 is not suitable for flotation due to its low solubility. Keywords: Mixed collectors, synergistic effect, scheelite

Jan 1, 2020

By H. Kuboyama

The synergistic effects of polymer additives such as gelatin and polyethylene glycol) (PEG) and Cl- on Cu electrodeposition have been investigated by measuring the polarization curves for Cu deposition, by rotating ring-disk electrode technique and by AC impedance measurements. The cathode potential for Cu deposition was greatly polarized in solutions containing both Cl- and gelatin or PEG, showing evident synergistic effect of polymer additives and Cl- on Cu deposition. The cathode potential was shifted to the less noble direction with increasing the concentration of Cl- in solutions containing polymer additives and showed the maximum polarization at Cl- concentration range between 0.1 and 1 mmol/L. The rotating ring-disk electrode technique revealed that Cu deposition in solutions containing small amounts of Cl- proceeded with initial formation of adsorbed intermediate CuClad. The Cole-Cole plots obtained by AC impedance techniques suggest that the reduction of CuClad is suppressed by polymer additives. The morphology of Cu deposited from solutions containing both PEG and Cl- showed the compacted surface composed of smaller grains due to an increase in the overpotential for Cu deposition.

Jan 1, 2007

By W. Breytenbach

Traditionally, dithiocarbonates (xanthates) have been the preferred collectors for the flotation of platinum-bearing sulphides. However, collector development has led to trithiocarbonates (TTC), which have proven to be very effective bulk sulphide collectors. The interest in TTC flotation behaviour is currently focused on the interaction of these collectors with other collectors, specifically the dithicarbonates. Batch-flotation research has shown synergism to exist among dithiocarbonate, dithiophosphate and trithiocarbonate collectors. Increased sulphide recoveries, both for the first-minute and final concentrate, were realized using mixtures of these collectors relative to the standard.

Jan 1, 2003

By Monserrat Rebolledo, John L. Uhrie, Candice Simms

Jetti Resources has developed a catalyst which overcomes the passivation of primary sulfides, enhancing the heap leach recovery of copper from chalcopyrite. It is important to emphasize that heap leaching of copper sulfides, whether with or without the Jetti catalyst, is a biooxidative process. We have demonstrated the efficacy of Jetti’s technology in bioreactors, with a chalcopyrite-dominant porphyry ore. In the presence of Jetti’s technology, optimal bioleaching conditions significantly increase copper extraction by 2.6 times that of the baseline.

Feb 1, 2025