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By C. M. Acuna, M. Sherrington

In high temperature processes thermodynamic equilibrium is assumed and therefore chemical potential of elements, among the condensed phases, have to be the same. In such situation impurities distribute accordingly and their fractional distributions are affected by the masses of the coexisting phases. It has been claimed Teniente Converters perform quite well for smelting high impurity concentrates, especially in respect to volatilization and/or slagging. Production of high matte grade near white metal composition, requiring moderate oxygen enrichment in the process air, results in a huge mass of gas and therefore a high fraction of impurities report to it. Similarly, by recycling different sources of slag, flue dust or other materials, the mass of the final slag is increased and so do the masses of impurities reporting to the slag. Nevertheless, above a certain level the recycling of smelter byproducts is no longer feasible and the cycle has to be halted, unless higher impurity mattes are accepted. Although the process might be continued during converting and refining, lengthy and expensive measures have to be taken if suitable anode copper for electrolytic refining is to be achieved. In the present study samples of high arsenic matte grade and slag were obtained on a pilot scale. The matte samples, on the order 75%Cu, were equilibrated with slag at varying ratios in magnesia crucibles under CO/C02 atmospheres at 1523 K. After 24 hours equilibrium matte and slag were rapidly solidified and analyzed by copper, sulfur, iron and arsenic. Furthermore, industrial samples of matte and slag, in the order 75%Cu at 1523 K, were obtained via a special quenching sampling device to determine the association of copper and suspension of matte and copper in slag. Based on the results, the distribution coefficient of arsenic between slag and matte was evaluated along with copper species in slag and the fractional distribution of arsenic, in the coexisting phases, was determined as a function of the ratio mass of slag to mass of matte.

Jan 1, 2007

By K. Niboucha, M. Zergoug, S. Brick-Chaouch, H. Houali

"Corrosion is an electrochemical process that causes degradation and deterioration of various steel works (pipelines, drains, cisterns) whether they are buried, immersed, or not. Worldwide, we estimate that corrosion destroys a quarter of the annual production of steel at a rate of 5 tons per second. Several techniques are used to protect against corrosion. Among these processes, Cathodic protection, which is regarded as the best technique to assure the protection of steel, works against this phenomenon. This is achieved either by a system of reactive anodes, or by the technique of impressed current protection or other techniques. Before any installation of cathodic protection, a preliminary study and pre-evaluation of certain parameters must be made. In the present work, we will present an example of dimensioning of an installation of cathodic protection by imposed current of a pipeline using solar energy, where we discuss the following items:•,Evolutions of the potential as well as current along the pipeline and their respective expressions deduced from the laws known as telegraphists;•,Range of protection (potential of protection along the pipeline);•,Influence of the isolation resistance of the coating on the range of protection;•,Effect of the aging of the coating and its influence on the current of protection."

Jan 1, 2005

By D. Ofstie, B. Kargutkar

BIM, or Building Information Modeling, is transforming the way metallurgical facilities are built, operated and maintained. BIM provides a digital representation of the facility, complete with all physical and functional characteristics - enabling collaborative planning, concurrent design, construction simulation, sustainable operations and predictive maintenance through a connected information model. Building on experience gained in other industries, Hatch is aggressively applying the BIM process to the mining & minerals processing industry to address inefficiencies inherent in traditional document-based information management. Intelligent 3D models support real-time quantity forecasting and cost trending by commodity type and construction work package. By linking procurement and schedule data, material availability and constructability reviews are visualized to verify construction critical path, ensure work front safety and minimize craft downtime. The BIM digital information model connects engineering, construction, commissioning and vendor data, aiding timely asset-centric handover to plant operating and maintenance systems.

Jan 1, 2015

By N. Vayenas, G. Yuriy

"The combination of a predictive reliability assessment model and discrete-event simulation can be an effective methodology to study the impact of equipment failures on the capacity of production systems in mines. In our case, a predictive reliability assessment model using genetic algorithms is combined with a discrete-event simulation model to analyze mine equipment systems.Discrete-event simulation involves modelling of real-life systems based on variables and events that occur or change at distinct points in time. The Simul8 simulation software, by Visual Thinking, is used in this research. It is a two-dimensional (2D), discrete-event simulation/ animation software tool for creating realistic depictions of manufacturing and materials handling systems.The simulation model developed for the purpose of this research represents a typical two-level, sub-level stoping section of an underground mine in the Sudbury region in Ontario, Canada. This 2D model was created to assess the impact of equipment failures to a mine’s production throughput. In more detail, using mean time between failures (MTBF) data of scooptrams derived from a reliability assessment model based on genetic algorithms, LHD failures are incorporated into the simulation model. These failures cause production interruptions to the development cycle and consequently loss of hauling capacity.Another purpose of this research work is to demonstrate how low-cost simulation tools such as Simul8 can be successfully applied to model underground hard rock mining operations. The research discussed in this paper is carried out by the Laurentian University Mining Automation Laboratory (LUMAL)."

Jan 1, 2005

By K. Soga

DOWA has long been specialized in the treatment of complex massive sulfide ores from exploration through smelting. Its competitive advantage derived from ore dressing technology to dress and concentrate complex ore to various kinds of metals concentrates. With this technology, the company recovers as many as seventeen different nonferrous metals. Therefore, it is crucial for the environment management and recycling business both to recover valuable elements like gold, silver, copper etc. and to handle hazardous elements in safety. From this view point, the nonferrous metal industry has a potential to play an important role; that is "The Anchor of Recycling" or "The Joint of Recycling Loop". By utilizing these mining, smelting and refining technologies, know-how and facilities, DOWA became a leading waste treatment, soil remediation and metal recycling company in Japan. This knowledge is now being applied in China .

Jan 1, 2007

The tensile test results of as-cast A356.2 grain-refined alloy castings show that the tensile strength can be improved by strontium modification (`SrM'), superheating at 900°C OM, and melt thermal treatment of the Sr-modified alloy melt (`SrMTT'). Both SrM and SrMTT processes can greatly improve the ductility (percent elongation) of the as-cast alloy. During solution heat treatment at 540°C, eutectic Si particles undergo fragmentation, spheroidization, and coarsening, thereby affecting their morphology. The effects of solution heat treatment on the tensile properties of the variously treated A356.2 alloy castings can be summed up as follows: the yield strength of the castings is significantly improved after 8 h solution heat treatment due to the precipitation of Mg2Si, after which it remains more or less the same with the further increase in solution treatment time up to 80 h; the ultimate tensile strength is also greatly improved within the first 8 h of solution heat treatment and then remains at the same level thereafter, up to 80h of solution treatment. The improvement in UTS is attributed to Mg2Si precipitation, dissolution of Si within the aluminum matrix, and changes in the Si particle morphology (spheroidization). The ductility of the as-received grain refined non-modified (`NM'), grain refined and superheated at 900°C (`SH'), and melt thermal-treated grain refined (`MTT') A356.2 alloy castings can be improved considerably with solution heat treatment e.g. from ~6% in the as-cast non-modified casting to ~10% after 80 h solution treatment.

Jan 1, 2011

By C. Schlumberger

INTRODUCTION The object of the present paper is to discuss, from a geological point of view, the practical results obtained by the authors with the method of the 'resistivity map of the subsoil' in the study of various mining problems. Some of the studies described date from 1920, 1922, and 1923. They are, therefore, quite old, at least as far as geophysical research is concerned (1). Others, on the contrary, are very recent (2). We shall deal only very briefly with the theoretical and technical sides of the processes employed. This paper has, essentially, a practical purpose, and it has seemed unnecessary to enter into a detailed discussion of the methods. Such a discussion cannot be presented without introducing ,quite. Complex considerations both of mathematics and experimental physics, which interest only the geophysicist: whose work is highly specialized.

Jan 1, 1931

By Karl Dufresne

Blasting in geothermally high temperature ground and/or extremely reactive ground is an increasing common challenge for surface and underground mines. Many current PETN based non-electric and electronic detonators have manufacturer published in-hole temperature limits ranging from 55°C to 65°C (131°F to 150°F). When confronting blasthole temperatures above the manufacturer published limits, operations may request site-specific guidance and qualification for use. The advised safe loading window for in-hole PETN based detonators is often too short to be practicable for production blasting. To overcome limitations of PETN based initiation systems, surface mines with high temperature ground and/or reactive ground are known to load blastholes with a qualified high temperature bulk emulsion that are top primed with a cartridge of temperature qualified detonator sensitive emulsion plus an RDX detonating cord downline. As there is no in-hole delay detonator in this system, blasthole timing is accomplished with surface delays. Although this system is safe, top priming and surface delaying does influence floor quality and top size fragmentation, and safe loading windows times reduce blast block size and increase blasting frequency. A mining company with a site characterized by geothermally high temperature ground plus highly reactive ground employed a blasting system like the one described above. The site desires to improve blasting performance by moving to an in-hole delay initiation system that can withstand the site ground conditions. At the request of the mining house, DynaEnergetics developed an electronic initiation system for application in geothermally high temperature ground and/or extremely reactive ground conditions. The DynaEnergetics IGNEO high temperature electronic initiation system is rated for in-hole use in ground up to 150C (302°F) for 48 hours. The detonator consists of a high strength detonator with an HMX base charge and thermally resistant downline. To make up a primer, the detonator is inserted into a booster charge assembly that is fitted with a small HMX shape charge. This high energy primer is designed to be compatible and reliable for firing bulk emulsions, including those with high percentages of urea inhibition to combat reactive ground. Up to 1000 detonators may be programmed in 1ms increments up to 1500ms. The system is controlled by a digital firing panel that can be used with either a wired or wireless trigger.  The system enables high temperature and/or reactive ground sites to utilize in-hole delay initiation and realize the associated performance benefits. Conclusions and Future Work 1] The HMX based electronic initiation system permits bottom in-hole delaying in ground temperatures above 80°C (175°F). As compared to top priming and surface delaying, in-hole bottom delaying is known to improve floor quality, muckpile fragmentation uniformity and reduce oversize. 2] Field evaluation of the HMX initiation system at the Lihir Mine is continuing. 3] Work on the next generation of the HMX initiation system is underway and will bring with it expanded application range and flexibility. 

Oct 1, 2024

The AG/SAG circuit discharge P80 is now increasingly referred to as the ?Transfer Size? or T80 for short. From the literature it is apparent that in circuit design some approaches to the sizing of AG/SAG mills as well as the ball mills that they feed use this parameter. This paper reviews whether the use of the T80 is appropriate in this context. In the course of the review examples of AG/SAG discharge size distributions measured from range of operating circuits are used to illustrate the arguments made.

Jan 1, 2012

By G. Riveros

A new, continuous fire refining process for copper has been developed and tested at the 5 tph pilot scale. During oxidation, the blister copper flows through a packed bed of crushed refractory bricks counter-current to a hot oxygen containing gas. The resulting desulphurized copper flows then directly into a packed bed of charcoal for deoxidation. By controlling the air to natural gas ratio, both temperature and reducing conditions can be controlled. Based on extensive laboratory scale measurements of the rate of copper oxidation and reduction, the process concept was developed aided by process modeling and simulation. The industrial-pilot scale installation built at the ENAMI Paipote smelter in Chile, consists of two cylindrical, compact reactors, operating in line, with a designed capacity of 5 t/h of blister copper. The results of the industrial-pilot tests confirmed the feasibility of the new process. The blister copper processing capacity was increased to 10 t/h with satisfactory sulphur removal. The degree of oxidation as well the copper temperature was controlled with relative ease. The specially designed siphon block allowed for smooth tapping of the oxidized copper and separation of refining slag. The reduction of oxidized copper in the packed bed of charcoal appeared to be very effective while control of the degree of reduction according to the height of the bed ensured control of the oxygen content in the refined copper at the required level.

Jan 1, 2007

By S. A. Briggs

Bioremediation has been accepted as a treatment technique for groundwater contamination in subsurface soils and shows promise for contaminated fractured rock environments. Biological growth in fractured rock is expected to occur predominantly as biofilms attach to the fracture surfaces. Biofilms in rock fractures are subject to a complex system of forces and other phenomenon due to the dynamics of the bulk fluid in which they grow. In this paper, through the applications of computational fluid dynamics (CFD) to rock fractures, where the boundaries are rough and the flow is complex, a precise analysis was conducted of the interaction of a fluid flow and the rock fracture. Specifically, hydraulic parameters and velocity profiles of an actual rock fracture were calculated and compared to a fracture of equivalent aperture. From the analysis it is clear that it is important to use more complex models such as the Lattice Boltzmann Method used is this paper to describe fracture flow.

May 1, 2009

By E. C. Sanford

A laboratory-scale batch extraction unit and operating procedure for studying the hot-water separation of bitumen from Athabasca tar sands are described. The extractor evolved from earlier units and has been in use by Syncrude Research for the past 10 years. By using a unit such as this, it is possible to study tar sand feed quality and the effects of chemicals on the hot-water extraction process, while process variables are held constant. Data are presented to demonstrate the importance of surfactants to the process and the interrelated role of inorganic bases and surfactants.

Jan 1, 1979

By C. J. Edmonds, R. Bland, W. C. Ferguson, R. Whitehead

"In 1969, the Environmental Science Division of James F. MacLaren Limited received authorization from The International Nickel Company of Canada, Limited to carry out a water quality monitoring program in the Lake Shebandowan region of Ontario, where a new base metal mining and milling complex was expected to go into operation in 1972. The objective of the program is to establish base-line water quality characteristics. Fully realizing their corporate responsibility to minimize the effects of the proposed activities on the environment, Inco decided that it would be desirable to establish a program by which any change in the quality of environmental waters will be detected before detrimental conditions ensue, permitting prompt corrective measures to be taken. The program has been in progress for over two years. The waters are sampled and analyzed four to six times per year. Sampling stations are located in Lake Shebandowan and on the adjacent Gold Creek - Matawin River system. On-site analyses and measurements are made of flow, dissolved oxygen, temperature and pH. Samples also are collected for later analysis in the laboratory. These samples are analyzed for a wide range of chemical and biological characteristics. The paper discusses the extent of the sampling program, the techniques utilized and the value of such programs in maintaining the quality of the environment."

Jan 1, 1973

By L. Zhu, S. Kaierle, M. Dahmen, C. Zimmermann, T. Haubold, I. Kelbassa, C. Mattern

Application of integrally bladed disks (blisks) is of increasing interest in compressors of aero engines. Blisks are preferred due to their potential for size and weight reduction, for increased performance and for reduced manufacturing costs compared to conventionally bladed disks. In case of a damage the blisk aerofoils cannot be simply replaced. If the damage is beyond acceptance or blending limits refurbishment is possible only by scrapping the whole blisk assembly, or more cost effective by the application of advanced weld repair methods. Weld repair of blisk aerofoils is challenging as it affects a critical part with specific requirements regarding its mechanical integrity, and as the accessibility is usually limited. The paper describes the ongoing development of advanced weld repair processes as part of a comprehensive repair strategy which have been developed for small-sized blisk assembly to give competitive maintenance cost.

Jan 1, 2006

By R. O. Grieve

"IntroductionCALEY (1945) and Evans (1950) pointed out that certain instances of convergence between Devonian and Silurian horizons, frequently evident in wells drilled for oil and gas in Ontario, appear to be related to local thinning of salt beds in the Salina formation and they suggested that leaching of the salt beds may have occurred. Exploratory drilling by Imperial Oil Limited since 1945 has brought to light several examples of structures similar to those discussed by Caley and Evans. The writer has had the opportunity to examine cuttings and data from wells which penetrated these structures and the attempt to interpret them in the light of the theory of leaching and subsidence proposed by Landes ( 1945a) to explain the marked brecciation and deformation of Upper Silurian and Middle Devonian sediments which crop out in the Mackinac Straits region of northern Michigan has led to the observations presented in this paper."

Jan 1, 1955

By T. Feldmann, G. P. Demopoulos

The adsorption of gold complexes on inorganic metal oxides has been mainly discussed in geochemical literature, but it is also of interest to the hydrometallurgical industry. This is so because it could be responsible for valuable metal losses or because it could potentially serve as alternative adsorbent material to activated carbon in certain cases such as from hot and acidic process slurries. This paper constitutes an early investigation into this subject by focusing on the effectiveness of FeOOH, Fe3O4 and Al2O3 as sorbent materials. All tests were done in a batch stirred-tank reactor under atmospheric conditions with synthetic gold(III)-chloride solutions at 23°C and 80°C, in the pH range of 1.6 to 9.0. Detailed kinetic tests were performed at different pH values (3 and 6) on FeOOH and Fe3O4 with solutions having gold concentrations from 5 mg/L to 130 mg/L. The adsorption of gold was found to be best both in terms of kinetics and loading characteristics at 80°C and pH=6. This was explained by a change in Au(III)-Cl speciation from a gold(III)-chloride complex to a gold(III)-chloride-hydroxy complex. By far, magnetite (reagent grade chemical) yielded the best gold adsorption characteristics making it an interesting sorbent material for further development considering that it can be advantageously recovered from slurry streams via magnetic separation. On the other hand, the tendency of gold(III)-chloro complexes to adsorb on metal (hydro) oxides needs to be taken into account to minimize undesirable metal losses in chloride-containing leaching media.

Jan 1, 2015

By B. B. Meadows

"The Minto-Chipman Strip Mining Reclamation Project was initiated to re-vegetate the spoil piles remaining from strip mining operations.All available information was studied by the team responsible, and areas being reclaimed in the U. S. were visited, Methods applicable to the N. B. Project were noted for future use.We have both surface and underground mining operations in New Brunswick, Both deface the natural landscape and reclamation varies in difficulty, Surface operation disturbances are the most difficult to correct.Some of the surface mining is carried out next to two main highways and the results are definite eyesores, With this in mind, it was decided to landscape the spoil ground next to the highways and plant “as is"" the ground remote from the public view.The landscaping entailed various degrees of bulldozing from complete levelling to contouring, smoothing and topping, Bulldozing is, of course, the most expensive part of any reclamation project.There are two phases to the planting program; experimental and operational--experimental both prior and, later, in conjunction with the operational planting.Initially in the experimental project, the pH and composition of the spoil was determined using a grid sampling system. Soil samples were tested in a laboratory at the University of New Brunswick."

Jan 1, 1970

Introduction ?MT involves the measurement of naturally occurring magnetic and electric field oscillations. ?The ratio of E/H (wave impedance) is measured as a function of frequency to give resistivitydepth information. ?The ratio of vertical and horizontal magnetic fields (tipper) gives information about the location of (channeled) current systems.

May 1, 2008

By R. R. Rogers

Introduction The subject of cathodic protection is not new. In 1824 Sir Humphry Davy, in publishing the results of his investigations for the British navy, pointed out that copper could be protected from sea-water corrosion by connecting it electrically with zinc or iron. Since that time much work has been clone in this field, particularly in the protection of metals from the action of sea water, neutral brines, and treated and untreated waters. Special mention should be made of the successful protection of underground pipe-lines which formerly were badly corroded by the water in the ground. So far, magnesium alloy and zinc anodes have been the most popular. However, fairly recent work has indicated that aluminium anodes will give good service under certain conditions. The principle of cathodic protection has been applied extensively in coating steel articles with zinc and in cladding aluminium alloy sheet with pure aluminium. A valuable discussion of the fundamentals and applications of cathodic protection recently was presented in the Corrosion Handbook. A useful list of references was included in the article.

Jan 1, 1949

By K. Ihara, T. Yamaguchi, K. Matsumoto

"Al-Fe alloy sheets having layers with different strain components were produced by unlubricated hot rolling and the recrystallization texture formation during annealing was investigated in each layer. In this study, the strain component introduced by rolling was quantitatively evaluated by measuring degree of bending of an aluminum pin embedded in the sheet. The textures before and after annealing were investigated by the SEM-EBSD technique. It was clarified that, in the middle layer, where comparatively small shear strain was introduced, ß-fiber subgrains and cube {001}<100> oriented subgrains were formed before annealing, and cube oriented recrystallized grains grew after annealing. On the other hand, in the surface layer, where large additional shear strain was introduced, shear texture components and cube oriented subgrains were formed before annealing, and shear texture was retained even after annealing, while cube oriented subgrains did not grow and were encroached. It was suggested that introduced strain components influenced the recrystallization texture formation by inducing different distribution of the subgrain size, stored strain energy and orientation relationship with surroundings before annealing.INTRODUCTION The microstructure developed during the hot-rolling process of aluminum and aluminum alloys affect the mechanical properties of the final product sheets. Especially, the crystallographic orientation in the final product sheets affects the r- value and ears during deep drawing (Humphreys & Hatherly, 2004), then the texture control in the hot-rolling process is important. When the friction between the rolling roll and rolled sheet in the hot-rolling is large, both the rolling texture and recrystallization texture tend to be heterogeneous in the thickness direction. It is known in many rolled aluminum alloy sheets that the texture in the surface layer was different from that in the middle layer because of additional shear strain. It was reported that in the vicinity of the surface layer, where large additional shear strain was introduced, the shear texture <1 1 1>//ND and < 1 1 0> // RD which contain components of {1 1 1} <1 1 0> and {0 0 1} <1 1 0> developed during rolling, and the shear texture developed even after recrystallization annealing (Sakai et al., 2002). Particularly, it is thought that the <1 1 1> // ND texture contributes to improve the r-value and press formability (Inoue & Takasugi, 2007). Therefore, asymmetrical rolling and high friction rolling have been applied to improve formability of aluminum alloys by adding shear strain in the rolled sheets as deep as possible (Kamijo et al., 1972; Inoue et al., 2005). However, few researches have been focused on the microstructures and texture before annealing and thus, the detailed mechanism is still unclear how the texture after annealing is affected by the texture before annealing. In this study, the Al-Fe alloy of commercially pure aluminum was chosen as the first material to be studied in order to clarify the fundamental process of the recrystallization texture formation. The main purpose of this study is to clarify the effect of additional shear strain on the rolling and recrystallization textures in the hot-rolled sheets by analyzing the transition of microstructure and orientation distribution through recrystallization annealing."

Jan 1, 2018