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By Stefan Mede

Automation in segment production doesn’t necessarily mean the use of robots. Several other aspects of automation in the process are available. Herrenknecht has collected many experiences in the automation process of carousel systems for segment production, implemented several robot systems and launched new artificial intelligence-based camera system supporting the production team in the quality control This paper is a follow up of the presentation on Automation in Segment Production held in 2021 at the RETC.

Dec 1, 2022

During the interval 1929-41, geophysical exploration in Russia made considerable progress, as reflected in publications. The greater part of these publications was available during the preparation of Geophysical Abstracts and Ms been abstracted in them. The rest was not received and remained unaccounted for. A considerable portion of these lading publications are now listed in bibliographic form, in view of their interest to geophysicists. All publications entered in the bibliography are in Russian. 1. GRAVITATIONAL METHODS 1. Abakelia, M. S. The Organization of Gravitational Observatories in Transcaucasia. Problemy Sovetskoi Geologi, Moscow, vol. 6, No. 5, 1936, pp. 452-454.

Jan 1, 1945

Rock mass classification systems are extensively used in rock engineering design work, and mine design is no exception. Among the systems most widely used for mining-related design work are the NGI 0-system (Barton et al., 1974), the RMR system (Bieniawski, 1976), the MRMR system (Laubscher and Taylor, 1976) and, more recently, the GSI system (Hoek et al., 1998). Classifying the rock mass is widely seen as being the fieldwork required to characterize the rock mass and enable the application of empirical design methods associated with the different classification systems. This paper argues that it is fundamentally important to recognize the distinction between rock mass characterization and rock mass classification. These two processes should, in most cases, be separated from each other. Rock mass characterization should be used to determine the intrinsic properties of the rock mass independently of the application; i.e. independent from the infrastructure to be designed, the size, shape, and orientation of the excavation(s) or pillar(s), etc. Rock mass characterization should also be compatible with most classification systems and empirical design methods to be used. Rock mass characterization is the background fieldwork required to perform rock mass classification and/or engineering design work. Rock mass classification is the subsequent step to the characterization, and an integral part of the design process. Parameters that vary according to the design, such as the relative orientation of geological structures compared to the opening or the mine-induced stresses, should be calculated as part of the rock mass classification and design process, rather than during the rock mass characterization process. The failure to distinguish between rock mass characterization and rock mass classification can lead to major design errors and poor results.

Jan 1, 2012

Every automatic citizen is an automatic recipient of a miner's right under the present Mining Act (Chapter 195), but this alone does not entitle any automatic citizen to mine for minerals on any land, even his customary group's land. Without complying with requirements of the Mining Act, any automatic citizen who engages in mining solely on the basis of a miner's right would be mining illegally. He would also be engaged in illegal mining if he mines on customary or other non-government land. Even if mining is legally pursued by an automatic citizen, he does not acquire ownership of minerals without first making the required royalty payments to the State.

Jan 1, 1991

By L. J. Vincze

The high cost of constructing mineral processing plants in remote locations warrants a close examination of the alternatives available for reducing the amount of on-site construction work. Among the alternatives are portable process plants, modular design and barge mounted plants. Each alternative has certain advantages as well as limitations depending upon specific conditions. On the basis of practical experience and engineering analysis, the paper examines the potential benefits to be realized by these techniques and summarizes the conditions required to obtain them. The potential savings indicated by such studies should encourage consideration of innovative design features for new plants located in remote areas.

Jan 1, 1980

By T. Velea

The most widespread methods for producing metallic copper are smelting of copper sulphide concentrates (which generates various types of polluting substances) and the hydrometallurgical route which consists of leaching in sulphate and chloride media (usually employing high temperature, high-pressure and special equipments). This paper presents a process, called VEPE, which consists of oxidizing copper sulphide concentrates in weak alkaline media (Na2C03 orland NaOH solutions), under low pressure and with air sparging. The oxidized concentrate contains less than 0.4% S. Copper is recovered from the oxidized concentrate by the standard leaching-solvent extraction-electrowinning route, with a total efficiency of 98% extraction. The proposed technology could represent a good opportunity to recover copper from sulphide concentrates in a clean, simple and profitable way.

Jan 1, 2007

By S. Orzecki

The KGHM Copper Refinery Plant, Glogów 1, has operated for 35 years and -increased its capacity almost ten times.Cathode quality, expressed in terms of the total impurity content, has undergone a five-fold improvement. The present refining capacity is equivalent to 240,000 metric tonnes of copper cathode, with a total impurity content of 20 ppm, inclusive of 10 ppm Ag. These accomplishments result from combined implementation of current technological progress in electrolytic refining and KGHM's own solutions applied to the Glogów Refinery. The quality improvement measures feature both lowering actual current density, despite an increase in nominal current density, and diminishing the role of non-ion mechanisms which transfer impurities to cathodes. The paper contains a detailed discussion of these issues and outlines possible measures aimed at further production and quality improvements.

Jan 1, 2007

Dragline performance drops considerably when chop-down and double handling of material is needed due to increasing overburden thick- ness or total pit depth. Beyond a certain pit depth the dragline needs support by a pre- stripping system in the upper portion of the overburden. In soft to medium hard ground the bucket wheel excavator can be used for pre- stripping, whereby several methods of material transport are investigated. Conveyor transport around the pit and dumping by stackers is the best solution from the technical point of view. Cross pit transport and dumping by means of a conveying bridge is the method with the lowest costs per volume moved. Cross pit transport by use of a beltwagon with overlong discharge boom is both, poor from the technical point of view and high in overall costs.

Jan 1, 1981

By E. S. Peterson, M. K. Harrup, K. A. Dolbeare, J. E. Wey

Efficient methods for removal of copper from heap leach solutions without mobile organic phases are a current mining industry need. To satisfy this need a selective, high-capacity, durable solid material is required. The INEEL has developed a set of materials based upon current solvent extraction chelates that provide selective copper concentration in the presence of high concentrations of iron. In contrast to conventional solvent extractions, our strategy anchors the chelators to a non-polymeric solid substrate through the use of a custom designed linker molecule. The fundamental synthetic routes to these materials have already been established and attachment to the solid surfaces achieved in an efficient manner. Our continuing research is focused on the optimization of the synthetic pathways to these solid materials and the evaluation of their copper capturing capabilities.

Jan 1, 2002

By L. W. Pommier, L. R. Plitt, F. B. Brien

L. R. Plitt (Assistant Professor of Mining and Metallurgy, University of Alberta, Canada.) — It is indeed encouraging to see rheological studies being carried out in a mineral engineering school. The bulk of the work being done today in applied rheology seems to be concerned with the behavior of polymeric solutions and thus has limited application to the solid-liquid systems encountered in mineral beneficiation. The authors have approached the problem by carrying out a dimensional analysis which showed that for power law fluids the drag coefficient, Ds, must be some function of a generalized Reynolds number which has the form: If the power law adequately describes the behavior of a fluid, the dimensional analyses predicts that the Ds - RN function should hold for all values of n' or any other dependent variable. The experimental evi-

Jan 1, 1968

By W. Rostoker, R. P. Elliott

TWO intermediate phases enter into equilibrium with the primary solid solutions of titanium.' The TiMn2 phase was identified by Wallbaum2 as of the C14 type isomorphous with MgZn2. Contrary to Maykuth, et al.,¹ the phase occuring at about the 50-50 atomic proportion has been shown to derive from a peritectoid reaction.:' A 30 day anneal at 900°C of an alloy containing 52 wt pct Mn developed sufficient of the new phase to give a clear and predominant diffraction pattern. The powder pattern was taken in a 14 cm diameter powder camera using filtered Cu Ka radiation. In all, 75 lines were recognized and measured. Interplanar spacing and observed intensities for the first 26 of these are given in Table I.

Jan 1, 1954

By C. Y. Kao, Roger Y. Cheng, C. S. Hsieh

The mushroom-shaped Minghu power cavern located in central Taiwan is 21.2 m (W) by 40.5 m (H) by 127.2 m (L) and is designed to house 4 units of power generating-pumping equipment with a total capacity of 1,000 MW. This paper presents an introduction to the geological conditions at the cavern site; the rock mechanical tests undertaken; the design approach adopted; the construction method and sequence followed; and the instrumentation provided in the roof arch to monitor the behavior of the surrounding rocks. The measured data collected from the embedded instruments will be compared with those obtained from theoretical analyses and presented in this paper. Several technical problems encountered during the construction stage are covered and the solutions of these problems are also described therein.

Jan 1, 1983

By Louis A. Panek

Most roof bolts are used in mines with bedded roofs, but it has not been determined to what degree thin-bedded roofs can be reinforced by bolting if there is no thick member in which to anchor the bolts, or what function the bolts must perform in such a case. Owing to widespread practice of systematic bolting to support thin-bedded roofs, moreover, it is desirable to design roof-bolting systems on a quantitative basis. Specifically, a solution to the following problem is required: For a roof composed of beds of given thickness and physical properties, what is the optimum length, spacing, orientation, and tightness of bolts consistent with safety and economy? The investigation reviewed here has produced a functional equation to evaluate these variables and establish basic principles of roof bolting.

Oct 1, 1955

By Louis A. Panek

MOST roof bolts are used in mines with bedded roofs, but it has not been determined to what degree thin-bedded roofs can be reinforced by bolting if there is no thick member in which to anchor the bolts, or what function the bolts must perform in such a case. Owing to widespread practice of sys- tematic bolting to support thin-bedded roofs, moreover, it is desirable to design roof-bolting systems on a quantitative basis. Specifically, a solution to the following problem is required: For a roof composed of beds of given thickness and physical properties, what is the optimum length, spacing, orientation, and tightness of bolts consistent with safety and economy? The investigation reviewed here has produced a functional equation to evaluate these variables and establish basic principles of roof bolting.

Jan 1, 1956

By K. P. Gupta, P. A. Beck, N. S. Rajan

By determining the a phase boundaries in the following ternary systems: V-Fe-Si (at 1175oC), V-Co-Si (at 1175°C), V-Ni-Si (at 1175oC), Cr-Mn-Si (at 1000°C), Cr-Co-Si (at 1175°C), Cr-Ni-Si (at 1175°C), V-Fe-A1 (at 1175°C) and Cr-Co-A1 (at 1175°C), it was found that Si exerts a stabilizing effect on these a phases, while A1 tends to destabilize them. Si atoms in solid solution occupy sites D in the a structure, The co/ao ratio increases with increasing Si-, Mn- or Fe-content. The volume of the unit cell decreases with increasing Si-content. THE stabilization of certain metal silicides (the Nowotny phases) by the addition of relatively small

Jan 1, 1961

By John S. Thayer, Frederick E. Brinckman, Kenneth L. Jewett, Gregory J. Olson

Interest and research in biorecovery of metals has focused mainly on cell-based metal leaching and precipitation. However, production of non-enzymatic metabolic products by microorganisms related to metals bioprocessing also deserves attention. For example, it is well known that biogenic inorganic (e. g. H2S04 ) and organic acids play a role in metal dissolution. There are other metabolic products of microorganisms which can catalyze useful metals transformations. These include methylated metabolites such as alkyl halides which can dissolve metals from ores and also reduce certain metal ions in solution to pure metallic particles. This paper describes some of our research on metal dissolution and precipitation by such metabolites. Examples include the production of high purity elemental metal particles of gold, platinum and palladium by volatile metabolic products.

Jan 1, 1989

Electrocrystallization studies were conducted in a concentrated acid-copper electrolyte to determine the influence of chloride ions and glue on copper nucleation and on the structure of thin copper layers. Electrochemical experiments allied to SEM and XRD examination were performed to characterize the mechanism of nucleation in the presence of additives at 65°C. Results indicated that most of the copper nucleation from a 83 g dm-3 Cu2+ solution, with 140 g dm-3 of H2SO4 is achieved in a matter of milliseconds, Although the presence of chloride and glue, at the concentration levels tested, does not seem to substantially modify the nucleation mechanism, the morphology, nuclei density and the copper film structure and orientation are changed by the presence of additives and by electrolyte stirring.

Jan 1, 1999

By H. Sato, R. J. Lipp, I. Iwasaki, K. A. Smith

Selective desliming holds much promise for upgrading low-grade, finely disseminated iron ores that are not readily amenable to conventional flotation. The process is extremely sensitive to the presence of calcium and magnesium ions that are in process water or are released by constituent minerals. The effects of these two alkaline earth ions on quartz were compared through streaming potential measurements, flocculation and cationic flotation tests, abstraction tests and scanning electron microscope studies. Calcium ion, adsorbed as CaOH+, and magnesium ion, attached by heterocoagulation as Mg(OH)2 precipitate, were responsible for the flocculation of quartz suspension and for the depression in cationic flotation of silica in alkaline pulp solutions. Magnesium hydroxide coating could be removed, similarly to adsorbed calcium ion, by complexation with EDTA and polyphosphates.

Jan 1, 1980

By Fathi Habashi

IT APPEARS that the phenomenon of ion exchange by which saline water was converted to sweet was known to Moses and Aristotle. However, the credit for the recognition of this process is generally attributed to Thompson (1850) and Way (1850), who reported that when a soil was treated with either ammonium sulfate or ammonium carbonate solution, most of the ammonia was adsorbed and calcium was released. It was later proved by Eichorn (1858) that the adsorption of ions from ground waters by clay constituents was a reversible process. The first attempts to utilize ion exchange phenomena was in the field of water softening around 1906, using natural and synthetic silicates. In 1935 Adams and Holmes in England observed that crushed phonograph records (phenol-formaldehyde and amine-formaldehyde resins) were capable of exchanging ions.

Jan 1, 1970

By Thomas Zukovich, Robert Morhard, Thomas Gelormino

The ExploTrack Explosives Tracking System is a sophisticated integration platform designed to track explosive products in both fixed locations and mobile environments globally, in real-time, on a 24/7 basis. The system utilizes active and passive RFID (Radio Frequency Identification Devices) installed within or applied upon explosives materials and explosives articles and incorporated within explosives packaging and logistic transport mechanisms. The system is designed for real-time inventory on an enterprise level and also across the globe providing explosives tracking, monitoring and explosives security from manufacturing throughout the logistics supply chain through use. The system can also track and monitor all known persons coming into contact with RFID enabled explosives materials and articles at the production level, at the magazine level, at the logistics level and to final use enabling a complete and real-time auditable chain-of-custody.

Jan 1, 2007