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By D. Nozadze

A new method of isothermal electro-contact diffusion welding of layered composites under pressure is offered. The scheme is developed and laboratory installation is created on which preproduction models of the layered composite of steel and aluminum is produced. A new method of electro-contact hot deformation is proposed for realization of diffusion welding by pressure of stratified blanks providing high-temperature isothermal process. In this case a rolling process or composite pressing is meshed with simultaneous electric current transmission in deformation center. Considering that a resistance of transient layer far exceeds the resistances of composite components, the heat release takes place intensively just in this layer. As the surfaces are approached over a distance of inter-atomic forces, the energy of boundary atoms easily reaches the energy threshold of capture with a formation of qualitatively new metallic bond. Proposed method, providing isothermal process in deformation center, excludes a necessity of previous preparation and prevention of surfaces. In this case strength of layer connection may approximate or exceed strength limit of cladding layer.

Jan 1, 2006

By D Xiong, G Xu, L Yao, F Wang, Y Duan

The goal of this project has been to digitise and use drill parameter data from rotary drilling (measurement while drilling; MWD) for a more effective planning of the blasting process in surface mines. A more accurate and reliable digital drilling and automatic hardness identification technology was developed, which includes both a hardware and software system. In the aspect of hardware, we designed a positioning, navigation and hardness perception terminal system which consists of a global positioning system original equipment manufacturer board, programmable logic controller and sensors of measuring major parameters, and a wireless data transmission system which combines digital blasting platform and wireless transmission facilities. In the aspect of software, we developed the navigation software of locating blastholes using LabVIEW and C++, and the blasthole design software using AutoCAD ActiveX (C#) technologies. This new technology is applied at Jiangxi Dexing Copper Mine, and initially realising the digitisation of drilling and hardness identification in blasting zone.CITATION:Duan, Y, Xiong, D, Yao, L, Wang, F and Xu, G, 2015. Advanced technology for setting out of blastholes and measurement while drilling, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 593–598 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

General recognition of the potential benefits of utilizing advanced technology has focussed public attention on the organisation of tertiary education. This has produced a situation where opportunities exist for significant changes to be implemented. The challenges to Mining education in this environment of change are analysed with respect to the setting of education objectives, the role of centres of education, course structures and student access to courses. The scope of the analysis includes formal courses for professional education and technical training, and programmes for continuing education and postgraduate research. Previous significant advances in mining technology illustrate the importance of encouraging the establishment of an extensive involvement with mining education. Education cannot be the sole responsibility of professional academic organizations; significant industry participation is essential. Methods of achieving this interaction are discussed. Major changes in techniques available for disseminating information provide a significant incentive to assess the relevance of existing course structures and restrictions on student access to courses. Establishment of a less rigidly progressive system of education is discussed with respect to the development of the full potential of computer based learning. This will expand the availability of mining education to include remote locations. The practical feasibility of such changes and recognition of the value of education as a commercial resource could also increase overseas involvement in Australian mining education. Benefits of such changes and problems that may develop if accreditation systems are not also changed to take account of new technology are outlined.

Jan 1, 1989

By Y Bissiri

The ever increasing demand for metals and minerals is putting significant pressure on current mining companies to find more ore. As these companies explore and mine, the future appears to be to go deeper and deeper underground. With depth, however, comes ever increasing costs as infrastructure such as hoisting, ventilation, the movement of workers and materials increase in size and scope. Further, the actual rock mass becomes prone to destruction through rock bursts and the heat generated becomes a major issue resulting in extreme expenditures in cooling plants and some of the biggest air movers in the world. All these issues result in dramatic changes in both capital and operating costs, subsequently making cut-off grades rise. As this trend continues there is an economic limit to how deep one can go, resulting therefore in a severe shortage of accessible ore deposits to mine. This paper discusses the need for larger marine robotics technology and presents the state-of-the-art in current research in underwater tele-autonomy, specifically the development of high bandwidth optical communication networks critical to any future activities (mining, construction, etc) underwater. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

By W. Dietzel

Fracture mechanics based techniques are used to gain insight into the phenomenon of stress corrosion cracking (SCC) and to develop guidance for avoiding or controlling SCC. From constant extension rate experiments under rising load or rising displacement conditions the susceptibility of high strength steels, aluminum, magnesium and titanium alloys to SCC and hydrogen embrittlement can be assessed. Such tests on pre-cracked specimens are also well suited for studying the mechanisms leading to SCC by employing appropriate models for the degradation of metallic materials which take into account the uptake of atomic hydrogen from the corrosive environment. Measurements of crack growth resistance curves using the crack tip opening displacement as fracture parameter can be compared with simulated R-curves obtained from modeling of the mechanism of hydrogen embrittlement. The materials investigated are a high strength steel and a magnesium alloy both exposed to environmental conditions which fostered the uptake of hydrogen.

Jan 1, 2010

Lead blast furnace water-jacket stability was investigated by examining samples from the Port Pirie Lead Smelter. The compositions of the phases formed in the samples were analysed using Scanning Electron Microscopy (SEM) and Electron Probe X-ray Microanalyser (EPMA). Phase equilibria analysis and thermodynamic modelling was undertaken using FactSage with latest thermodynamic database for the slag/matte/metal/speiss/solids multi-component Cu2O–PbO–ZnO– Al2O3–CaO–MgO–FeO–Fe2O3–SiO2–S major and As–Bi–Sb–Sn–Ag–Au minor elements system. Results indicated that the stability of the water-jacket steel wall without freeze-lining is influenced by formation of the complex Fe-rich speiss phase at critical As concentrations. The integrity of the furnace walls with freeze-lining is critically dependent of the stability of the oxide-based freeze-lining which is dependent on various factors including most critical one—the proportion of solids determined by the slag chemistry and fluxing. Thermodynamic modelling of the lead blast furnace operation indicated limiting thermochemical conditions for the water-jacket stability. Factors and controls critical to the water-jackets integrity are discussed.

By C. Pichler, S. Luidold, C. Wagner, C. Sagadin, D. Kreuzer

Engineers and scientists have been combating the attack upon refractory materials of molten metals/matte and slags for hundreds of years. The details in many cases are still questionable or at least debatable. The corrosion is a major concern for furnace operators as refractory wear or failures inevitably results in reduced production efficiency and furnace reliability. Also the cost to industry is considerable and only a thorough understanding of all the complexities of the process will help to minimize that cost. One of the critical questions to overcome is the correct selection of refractories for the individual process steps to provide long and predictable refractory life together with high furnace availability. To understand the nature of the reactions involved in refractory corrosion, it is crucial to determine the complex thermo- chemical equilibria of the reactions occurring between the refractory materials and the process phases. A simulation model coupled with commercial software like FactSageTM is demonstrated aiming to understand the corrosion mechanisms between refractories and the molten process phases and draw implications for improving the performance of refractories and refractory lifetime. INTRODUCTION The extraction or recycling of valuable materials, e.g. metals, can be done by two main routes, pyro- and/or hydrometallurgical processing, depending on the chemical behavior of the used ore, scrap or pre-treated concentrate. Sometimes it is also necessary to use both process routes for the extraction or the recycling of valuable materials. In the case of a pyrometallurgical treatment, the usage of refractory materials is inevitable. This is mainly caused by high temperatures, prevailing during processing. The interaction between refractory material and slag, metal or matte leads to different reactions and interactions. As a main result corrosion of the furnace lining (refractory material) takes place. Hence, recurring furnace shutdowns occur for renewing the refractories. This leads to reduced production efficiency. Such refractory lifetimes are between some hours and decades, depending on the processes.

Jan 1, 2019

By K. G. Kebkal, R. Bannasch

"Because the operation of tethered underwater vehicles in the deep ocean or under drifting ice areas is very complicated or impossible, the application of autonomous underwater vehicles (AUV) is preferred or even the only possible solution. However, this implies the possibility of a direct and real-time control over all AUV functions, which is only achievable with the availability of accurate positioning/navigation and a high-speed communication link. This paper presents a flexible bottom- or surface-based solution enabling high positioning accuracy of underwater objects (harvester, AUVs, bottom nodes); specifically, a multifunctional system that combines Ultra Short Baseline (USBL) transceivers and Long BaseLine (LBL) stations deployed at a large depth. Moreover, each baseline transponder is equipped with a high-speed communication device to provide the means for real-time AUV control based on the information about its current position, e.g. navigate it with direct commands and operating its actuators and other mechanisms. Moreover a communication link with a high data rate can provide valuable visual information from the operation area.Depending on how many nodes the LBL grid comprise has, target transponder positions can be estimated with an accuracy of several to tens of centimetres. The purpose of the paper is to present the experiments with all key elements of the multifunctional Hydro-Acoustic USBL-aided LBL Positioning and Communication System."

Sep 1, 2014

By V S. Mutton, M J. Shearer

"The current economic challenges faced by the mining industry led to a review of options for reducing the cost of ventilation control devices (VCDs). The VCDs at the Mount Isa Mines site operated by Glencore in Queensland typically experienced significant damage on the operating levels and required expensive replacements. Ventilation controls can become damaged by the effects of stope firings. This paper discusses the nature of blast wave effects, giving consideration to distance from the firing and changes in mine geometry. The time taken to adjust the airflow on the operating levels with the current VCDs resulted in the loss of productivity opportunities. The mine site engaged an equipment supplier to collaborate on the development of a high-strength regulator to control the required airflows within its underground workings.The strengthened regulator proved to be cost-effective and provided additional benefits, including ease of use, simplicity of installation and speed of change in the control of available ventilating airflow. An added advantage of the re-engineered regulator compared to contemporary VCDs is its flexibility, which includes the ability to easily move mobile equipment into different ventilation districts where required without the need to remove the VCD from its location. This paper describes both the innovation and environmental sustainability approaches followed when developing the new regulator for its implementation at the site.CITATION:Shearer, M J and Mutton, V S, 2015. Advanced ventilation control – an analysis of innovation and environmental sustainability, in Proceedings The Australian Mine Ventilation Conference, pp 55–62 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Aug 31, 2015

By C Xu, B Li

Multi-sensor fusion visual perception technology significantly enhances visual perception capabilities in complex and harsh environments by combining visual data from different sensors. This technology is especially useful for scenarios where traditional single visible light sensors, such as standard cameras, struggle due to poor lighting, adverse visual conditions, or other visual obstructions. In environments with low light, smoke, or dust, the performance of conventional visible light sensors degrades, limiting their application. By integrating data from various sensors like radar, infrared thermal imaging, and others, multi-sensor fusion technology provides a more comprehensive and complementary visual solution. This fusion not only enhances the robustness of visual systems but also greatly expands their potential applications in fields like visual surveillance. In recent years, deep learning methods have become the mainstream technology for addressing multi-sensor fusion issues, demonstrating significant advantages in adaptive feature selection compared to traditional machine learning methods. However, deep learning-based multi-sensor fusion algorithms still face several challenges. The design of network structures is often redundant, lacking effective screening of useful components within multimodal information. Mainstream fusion algorithms focus excessively on improving display effects without adequately considering the needs of downstream applications and tasks. Existing fusion perception algorithms are generally designed for open visual scenes and lack targeted design for complex visual degradation factors present in tunnel environments of mines. Current deep learning methods for designing multi-sensor fusion networks heavily rely on manual experience to create fusion modules. This reliance increases the complexity of network design and can lead to redundancy. Redundant network modules are difficult to identify in end-to-end learning tasks at this stage, significantly slowing down network inference and potentially interfering with the output of fusion perception. Additionally, training these fusion modules typically requires large amounts of well-annotated multimodal data, further increasing implementation difficulty and cost. For instance, the fusion network design proposed by Li and Wu (2018) focuses on extracting multimodal fusion features, while Zhao et al (2020) introduced a feature decomposition mechanism in the feature fusion and extraction modules. Researchers like Zhang and Ma (2021), Xu et al (2020), and Liu et al (2017) have attempted to improve network structures through dense cascades and the introduction of residual connections. Although these methods have improved the handling of multimodal information to some extent, they still face limitations in distinguishing between useful and redundant information, with redundancy persisting in network designs. Ideally, the design of fusion networks should be more intelligent, guiding network structure design heuristically based on the importance of different modal information for the current task. This would reduce information redundancy and network weights, requiring the development of new algorithms or frameworks capable of automatically identifying and optimising fusion strategies, thereby reducing dependence on manual experience while improving fusion efficiency and network performance. Current deep learning designs for multi-sensor fusion algorithms often overlook the

Sep 1, 2024

By D. McCarthy

This paper discusses the process involved in developing an optimum method of treating and removing heavy metals from water that have leached out from the native rock -prior to discharge back into the environment. Also designed into the system is a manner to stabilize the metals removed as a precipitate, so that they can be disposed of as a non-hazardous waste.

Jan 1, 1992

By E Jak, M Shevchenko, D Shishin

One of the key aspects to develop sustainable metallurgical production is to ensure that the predictive power of thermodynamic tools is brought up to a new level of accuracy and reliability. Exploring new polymetallic processes, integrating primary and recycled materials, means utilising the uncharted areas within the Cu-Pb-Zn-Fe-Ca-Al-Mg-Si-O (major) – Cr-Na (slagging) – As-Sn-Sb- Bi-Ag-Au-Ni-Co (minor) slag-solids-metal-matte-speiss-sulfate system. This requires extensive integrated experimental and thermodynamic modelling study, which is underway at PyroSearch at the University of Queensland (UQ).

Aug 21, 2024

By J. S. UNGER

A LARGE proportion of the coke used is made in the by-product oven from the high-volatile coals mined in the adjacent district. At the beginning it was feared good by-product blast-furnace coke could not be made with our coals. By experimenting with various mixtures of coals, coking time, oven design, and coking temperatures, much has already been accomplished. The results show that a hard, dense coke, not easily broken by handling, can be produced. In its present state it is not all that could be desired, but it is being constantly improved. Such coke has been used alone as the fuel on several of the blast furnaces producing the highest daily production in the Pittsburgh district. Many of the coals in the Pittsburgh district when coked in the by-product oven yield a gas which contains a high percentage of sulfur, which is objection- able for many metallurgical operations. As this fuel is gradually replacing the ideal fuel, natural gas, which is becoming less plentiful, studies are being made of the best methods for purification. Some metallurgists believe sulfur to be a very injurious element in steel. Recent investigations by Government bureaus, scientific bodies and private firms, seem to indicate that a reasonable amount of sulfur may exist in steel without detriment. Without wishing to provoke any metallurgical controversy on the subject of sulfur, the fact remains that the daily purification

Jan 1, 1926

By A. Dadgar, R. H. Sergent

Changes in the ore types available and increased environmental concern have created a demand for an alternative technology to cyanide for the extraction of gold from ore. Great Lakes Chemical Corporation (Great Lakes) believes that halogen chemistry, in particular bromine chemistry, is the best available alternative to cyanide for gold extraction. Great Lakes is a Fortune 500 chemical company with sales of approximately one billion dollars per year. Great Lakes extracts elemental bromine from naturally occurring brines in Southern Arkansas. Great Lakes has developed a family of proprietary bromine compounds to aid in the extraction of gold. In addition to proprietary bromine compounds for gold extraction, Great Lakes has developed a method of recycling bromide ion in the leach circuit. Various recovery methods, including ion exchange and solvent , extraction are currently being studied.

Jan 1, 1990

By M. Fan, M. Mankosa, G. Luttrell

"Column and other non-conventional flotation approaches continue to provide benefits where conventional flotation processes have exhibited limited success. This is particularly evident with respect to flotation of ultrafine and coarse particles. Advancements in air sparging technology have provided the ability to produce finer bubbles than previously possible. The generation of finer bubbles coupled with the froth washing capabilities of a flotation column has demonstrated improvements in ultrafine particle recovery while simultaneously producing a high-grade float product. On the other side of the spectrum, the use of these sparging technologies while applying flotation fundamentals to a fluidized-bed reactor has increased the maximum floatable particle size up to and in excess of 3 mm. Benefits of higher recoveries and reduced reagent consumption have resulted from the use of these technologies. An additional benefit includes a reduction in plant grinding requirements. As such, this paper describes the application of Cavitation-Tube sparger technology and fluidized-bed flotation (HydroFloat). A review of data from industrial and pilot-scale applications is also provided.INTRODUCTIONConventional (mechanical) froth flotation is considered the workhorse of the minerals processing industry. This low-cost process makes it possible to selectively recover minerals by exploiting the difference in surface characteristics (e.g., wettability) of the valuable component and the waste material. Unfortunately, the upper particle size limit for flotation rarely exceeds 0.600 mm, and is typically maintained at less than 0.300 mm for most industrial applications. For many commercial base metal plants, the particle size range for optimum recovery is typically between 0.01 and 0.1 mm (Lynch et al., 1981). This finding is not novel. In fact, the effect of particle size on flotation recovery was studied as early as 1931 by Gaudin et al. who showed that coarse (+0.250 mm) and extremely fine particles (-0.010 mm) are more difficult to recover than particles of an intermediate size. The loss of recovery is due to inherent limitations associated with the flotation process, including bubble-particle adhesion and collision, detachment, buoyancy, and transport."

Jan 1, 2010

By L. Iacopetti, A. Calderara, M. Perego, P. Perrone, T. Furusawa

De Nora, a global leader in the development, manufacture and sale of all DSA® anodes based on titanium coated with mixed metal oxide (MMO) for electrochemical processes will present key advancements made to Self-Protected Anodes (SPA) for metal electrowinning. (DSA® is a registered trademark of Industrie De Nora S.p.A., Italy). In 2017 pre-commercial demonstration cells were operated in industrial environment. The program’s focus was to fully demonstrate the SPA anode’s superior mechanical and electrochemical robustness during normal and induced dendrite shorting occurrences while providing quality of plating in commercial operation. De Nora specialists focus on key components, in particular the engineering of the self-protection system, DSA® anodes and catalyst formulation capable to cope with high levels of pollutants while providing long service life in the meantime. Results of field trials confirmed the expected anode performance and enabled the selection of the most suitable “SPA” structure, based on resistive protective elements. Summarizing the economic benefits to copper electrowinning tankhouse operation with De Nora’s self- protected all DSA® anodes are; Double-digits power savings Cobalt-free electrolyte operations Minimal dendrite shorting damage incurred at the SPA anode Smoother, uniform cathode deposits with tangible improvement on current efficiency Tankhouse operations producing lead-free copper quality cathodes, in addition to elimination of lead waste for improved operator health and environment. INTRODUCTION De Nora’s engineered “Value Technology Package” (“VTP”) for electrowinning, consisting of our DSA® anodes coated with mixed metal oxide specifically formulated for copper electrowinning in conjunction with an advanced self-protected full titanium anode (“SPA”), underwent an intense field qualification program, inclusive of the behavior under massive short-circuits as part of the field investigation, with the goal to select and appoint the ultimate design configuration of “SPA”. Optimized wireless-based monitoring system was included in the field program, demonstrating good functionality for cell parameters monitoring and remote shorts detection.

Jan 1, 2019

By T Roesch, M Neurohr, S Stratton

"Dwindling commodity prices are forcing today’s mining operations to increase output. Sometimes the solution is to upgrade the existing infrastructure; however, in most cases it has to be achieved with the same or reduced workforce and with the same equipment capacity through improved process efficiency and higher uptime.Measure, Manage and Improveis the mantra for this years’ Mill Operators’ Conference and while this in most cases relates to the above process efficiency, Siemens has set its focus on the availability and uptime aspect since unscheduled downtime is one of the biggest threats to any grinding operation. Pinion misalignments, resonance, unbalance and bearing and gear meshing faults in geared trains, as well as long-term changes in the condition of the mechanical components or structures and auxiliary systems in gearless systems are the main reasons for unscheduled downtimes in today’s mill drive trains. Our paper outlines the efforts that have gone into adapting conventional condition monitoring methods in conventional, pinion driven mill drive trains as well as gearless systems to capture the gradual deterioration of wearing parts or structural changes in the drive train not only on fixed speed application but also on variable speed applications with multiple operating points. The paper further explores the use of condition monitoring systems as a tool to assess spare thermal motor capacity to potentially push equipment beyond its nameplate rating, along with the process that was followed to correlate measured frequency spectra and envelopes to ambient and load data to understand the kinematics of the drive train.Citation:Neurohr, M, Stratton, S and Roesch, T, 2016. Advancements in Condition Monitoring on Mill Drive Trains for Proactive Maintenance and Early Fault Detection Purposes, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 263–272 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

By Shani Engelbrecht, Belinda McFadzean, Avuyile Wali, Natalie Shackleton, Vratislav Malysiak

Frothers play a crucial role in sulphide and PGM ore flotation recovery, and AECI Mining Chemicals studies on PGM ores have shown significant flotation kinetic increases with the optimal frother-collector combinations. Using Senfroth 200 as the industry baseline, remarkable kinetic increases were observed with AECI Mining Chemicals developed frothers in the first concentrate. Even in the worst-case scenarios, 4E PGM recovery increased by 5% at a slightly higher concentrate grade. It is important not to limit frother dosage to a fixed value. Instead, enough frother should be added to maintain a stable bench float, measuring the dosages by frother volume before and after tests. Frothers can be specialized blends and their importance should not be underestimated. The results produced by formulating and innovating frothers to address specific industry challenges have been encouraging. Testing a frother on a plant scale does not have to be as daunting as with collectors, enabling the identification of the best frother-collector combinations at an industrial scale. AECI Mining Chemicals bench scale testwork has motivated plant-scale trials that have successfully transitioned to commercialization. This paper compares the results from metallurgical and froth stability tests and shows that occasionally frothers that have a less stable froth can have improved valuable mineral recoveries, while still exhibiting better drainage for reduced entrainment and mass pull. It was shown that caution should be used when relying only on simplified froth stability tests in the evaluation of new frothers.

Feb 1, 2025

By Trevor Riters

Advancements in Emerson’s instrumentation technology have brought value and efficiencies to the mining industry. Some think of instrumentation as basic sensors and valves, but with our solutions, we equip operators with real time, accurate, and reliable data that they can use to operate more effectively. Working with Caltrol, an Emerson Impact Partner, we successfully engineered wireless skids for a leach pad to provide precise measurement and control of raffinate solution to many of the large mine sites in Arizona.

Feb 1, 2025

By David Ulrich Furrer

Materials and manufacturing processing technologies have played an important role in the development and capabilities of nearly all manmade products. Market drivers for fuel efficient, low cost, environmentally friendly, more capable transportation has given rise to significant materials challenges and subsequent developments. The rate of improvement and implementation of new commercial products can be limited by the rate of new materials and process technology development and qualification. As many materials are being designed for unique requirements and even location-specific unique properties, the implementation of tools and methods to enable rapid characterization and validation of material definitions and design systems must also be accelerated. A review of new integrated material, manufacturing process and component designs, engineering processes and emerging tools and methods will be discussed. The linkage of computational materials science and engineering into component design will also be discussed along with the challenges and opportunities for further growth and application of integrated computational materials engineering (ICME).

Jan 1, 2015