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By J. A. Espinosa-Guillen, J. A. Lopez-Molina, S. García, J. A. Valencia-Quintanar

"The design and implementation of grouting treatments in rock masses are procedures that require continuous adjustment of parameters and criteria to optimize the results. In this proposal we describe a set of tools that enhance decision-making for this type of jobs particularly in dam projects. The methodology is focused on hydrogeological zoning of the site and its constant update combining engineer’s experience with artificial intelligence techniques to integrate the site knowledge; as well as the evaluation of grouting results for different scrutiny scales, with special attention on the relationship between water absorption and grout consumption. INTRODUCTIONSeveral methodologies for design, implementation and evaluation for grouting rock masses have been developed for the solution of specific problems and tested in diverse geological conditions. Each of these methodologies is focused on results evaluation for different scrutiny scales (Table 1) and is employed to assist decision-making before or during the grouting process.Some methods define specifications for grouting each stage of the borehole, making theoretical, semi empirical or experience-based considerations to define basic parameters as maximum pressure, maximum volume, grouting time, flow rate, etc. Ultimately each approach aim to optimize the injection process, adjusting volumes or the grouting time required to obtain satisfactory results, reducing risk of creating new flow paths or unnecessary grout travels, and enhancing the mixture properties to achieve adequate penetrability and long-term behaviour. Some of these criteria have been widely used in dam projects, for example the concept of Grouting Based on Facts to define the maximum pressure and volume (Ewert, 1997), the GIN method (Lombardi & Deere, 1993; El Tani, 2012), or the North American standards based on Apparent Lugeon measures (Naudts, 1995; Bruce 2011); on the other hand, there are relatively new criteria that have shown good results for dam grouting as the Aperture Control Method (Bonin et al., 2012; Carter et al., 2012) or the Real Time Grouting Control Method (Stille et al., 2012)."

Jan 1, 2015

By Asbjørn Solheim

The service life for aluminium reduction cells is often limited by the cathode carbon, due to preferential wear along the periphery of the cell leading to the so-called "W" wear pattern. The reason for this preferential wear is not well understood. Two mechanisms are suggested in the present paper; 1) non-stationary dissolution of aluminium carbide into a layer of sludge that periodically forms and disappears, and 2) electrochemical formation and dissolution of aluminium carbide within an aluminium carbide layer containing bath-filled pores. The latter mechanism may be related to the high local current density at the periphery of the cathode.

Jan 1, 2011

By H. Dundar

The first application of High Pressure Grinding Rolls was in 1985 at a cement plant, for the purpose of capacity improvement. Then various circuit configurations were derived to achieve a reduction in overall specific energy consumption, by transferring more of the grinding required to the HPGR. In most circuit configurations, the recycle of fines is required for effective breakage between the rollers. By increasing the fines amount in the feed material to a specific level within the recycling load, a uniform material bed is created and a higher pressure gradient along the roller width is obtained, resulting in compact flakes, including more fines. The fines recycle results in enhancement of the interparticle breakage. This paper will discuss the effect of the feed size distribution on HPGR performance.

Jan 1, 2012

By F. H. Samuel, P. Burke, F. Mucciardi, J. Gruzleski, S. A. Musmar

A new thermal analysis technique has been developed and tested. It utilizes the enhancement in heat transfer characteristics associated with a recent advancement in heat pipe technology. Heat is extracted from a liquid sample of a melt taken in-situ within a vessel or furnace. The rate of heat extraction is such as to cause the sample to solidify. The technique was tested in both laboratory scale and industrial scale (Grenville Castings, Perth, Ontario). A 356 Al Alloy, subjected to various melt treatments was used to perform the tests. Classical thermal analysis was also performed simultaneously using a preheated graphite cup and at the same melt conditions. The comparison showed the potential of the new technique over classical thermal analysis. The major advantages of the new method are that it conducts the analysis inside the melt (i.e. a physical sample is not removed from the melt), it consumes less time and the cooling rate can be precisely controlled during the solidification process. Moreover, the resolution of the results is better than that of conventional techniques. Aluminium

Jan 1, 2006

By China University of Mining and Technology, P. Zhang, C. Zhou, C. Duan

"Recovering pyrite from the gangue with high sulfur content is of great significance for both economic development and environment protection in China. Due to the global water shortage and high cost in wet separation processes, it is urgent to explore more efficient energy and water conservation method in mineral processing field. This study has proposed an innovative method based on density difference for fine pyrite enrichment by vibration fluidized bed. In this study, the total sulfur content (TSC) of the gangue sample is 19.18%, and the pyrite is disseminated with fine granularity in the gangue which should be crushed for dissociation. The combination and dissociation experiment of -6mm gangue shows that the dominant density of -6+3mm, -3+1mm and -1+0.5mm comminuted material is +2.9g/cm3. Based on the analysis of characteristic, the effects of various factors on the separation performance were experimental studied. The results show that gas velocity, vibration intensity and bed height all have the significant effects. With the increases of superficial gas velocity, vibration intensity and bed height, the separation performance all presents a decreasing tendency. Additionally, the TSC of -6+3mm, -3+1mm and -1+0.5mm materials are respectively up to 37.94% , 35.43% and 30.61% at the optimum conditions, which are the 1.72?1.90 and 2.29 times as much as the TSC of raw material, respectively. This study demonstrates the vibrated fluidized bed can recovery pyrite from the gangue effectively.INTRODUCTIONWith the increasing mining and separation of coal, the yield of gangue has a further growth tendency, which has become one of the largest reserves of industrial waste (Querol et al., 2008). However, many harmful elements, such as S?NOx and Hg, is existed in the gangue leading the serious damage to the soil and environment (Hao, Yun, Zhanyuan, Sen, & Song, 2013). In addition, the economic would be suffered from the loss resulting in the occupied of arable land caused by the accumulation of gangue (Yeheyis, Shang, & Yanful, 2009; Zhou, Liu, Yan, Fang, & Wang, 2012). Therefore, the government has put forward the policies of ""green mining"" in China (Xing & Gao, 2009; R. Zhang, Ai, Zhou, Ju, & Zhang, 2015; Zheng, Du, Li, Qiu, & Yang, 2015). Among different research areas of coal utilization, extracting the useful minerals has become one of hot topics (Ledin & Pedersen, 1996; P. Patra & Natarajan, 2003; Partha Patra & Natarajan, 2004). At present, many researchers has devoted to the desulfurization of coal all over the world. As result, the sulfur element, which is mainly existed in the presence of pyrite, would transferred in the tailings, namely the gangue. Meanwhile, the pyrite is important raw materials to produce rubber, paper, textile and match. Consequently, recovering the pyrite from the gangue is not only suitable to the requirement of ""green mining"", but it could turn the waste into the treasure having the important significance."

Jan 1, 2016

By Harold Hopkins

THE Wright-Hargreaves mine is one of a group of seven mines long active in the Kirkland Lake district, Ontario. Detailed geological reports and maps covering the area have been published by the Ontario Department of Mines (1,3)t. Though all these mines work several productive veins there is one vein which is common to all and is known as the North Vein of the camp?not that it is the most northerly vein mined, but it is the more northerly of the two major veins of the camp. At the Wright-Hargreaves mine there are in all ten important producing veins, and most of them have a N.60°-65°E. strike and in general a steep southerly dip. It is a common belief that most of these veins lie along faults but it will be shown that whilst this is true of some of them it is not true of all, and also that a vein may lie in a fault along part of its course and elsewhere fill a fracture in line with the fault, this being a consequence of rotational movements that took place during faulting. The paper describes the history of faulting at this mine in particular, makes observations on the principal pre-ore fault, and describes the method used in solving the movements on the post-ore faults. Other details of geology are not discussed except to mention here that our main veins lie almost entirely in the syenite porphyry stock except on lower levels close to the east boundary of the property, where the North vein leaves the porphyry to enter the greywacke.

Jan 1, 1940

By D. W. Heard

Electrospark Deposition (ESD) is a low heat-input, high energy density, micro-welding process. The short pulse duration and high-pulse frequency, in combination with the small amount of material transferred during each pulse, results in the evolution of extremely rapid cooling rates, believed to approach 105-106 °C/s [1]. This rapid solidification event results in the refinement of the microstructure to the nanostructured or amorphous level [2, 3]. Figure 1 displays the resultant microstructure of an Al-17%Si alloy deposited by the ESD process. Furthermore, it was determined that the microstructure of the deposit remained unchanged after subsequent layers were welded onto the presented layer. Freeforming of materials is a rapid prototyping process in which the deposited feedstock is built-up to the desired geometry in a near-net shape manner. Figure 2 displays the automated set-up employed produce three dimensional freeformed objects via multiple deposition trials of the ESD process. The automated XYZ table is equipped with CNC software to transform CAD renderings into three dimensional tool paths. Figure 3 displays an Al-12Si freeformed gear (2" diameter, 12 teeth) produced by the ESD process, prior to removal from the substrate. An SEM analysis of the freeformed component showed that the microstructure did not coarsen during the deposition of subsequent layers during the freeforming process, as depicted in Figure 4, resulting in the production of a bulk nanostructured component. This paper represents a summary of the capabilities of ESD to fabricate advanced materials possessing refined microstructure. In particular, results on the microstructural evolution obtainable for various wear-related systems will be presented. In addition, the feasibility of using the ESD process to freeform three-dimensional objects via multiple deposition passes will be presented and accompanied by a characterization of the properties of the freeformed component. [1] R. N. Johnson, "ElectroSpark Deposition: Principles and Applications," in Society of Vacuum Coaters, 2002, pp. 87-92. [2] J. Milligan, D. W. Heard, and M. Brochu, "Formation of nanostructured weldments in the Al-Si system using electrospark welding," Applied Surface Science, vol. 256, pp. 4009-4016. [3] S. Cadney and M. Brochu, "Formation of amorphous Zr41.2Ti13.8NilOCul2.5Be22.5 coatings via the ElectroSpark Deposition process," Intermetallics, vol. 16, pp. 518-523, 2008.

Jan 1, 2010

By M. J. A. Ruszala

Aggregates production is a huge global industry which uses an enormous amount of energy and produces a massive amount of unsalable fines. Reducing the amount of energy used per tonne of product and/or the amount of fines produced, would make a quarry more efficient. This reduction would make the quarry more environmentally friendly and profitable. This research looks at modelling Mountsorrel Quarry, a granite quarry in the United Kingdom (UK), using JKSimMet and Split-Desktop software packages in conjunction with the European Union (EU) project, EE-Quarry. Samples submitted to drop weight tests confirmed Mountsorrel Quarry granite as an extremely hard granite. Rock fracture data (t10) and energy of comminution (ECS) data were obtained from analysing the results. Split-Desktop image analysis software was utilized to determine the particle size distribution (PSD) of the primary crusher feed, as it contains particles too large to screen manually. It was also found that <1% of the feed is fines, which at Mountsorrel Quarry are classed as particles smaller than 5 mm, and that no particles were larger than 3,810 mm. JKSimMet was used to create a flowsheet of Mountsorrel Quarry. The crusher product PSDs were simulated and found to have strong correlations with experimental data, calculated by screening samples from conveyor belts, especially in the fines region, with a mean difference of 1%. The simulated primary crusher product PSD showed that it contains ~6% fines. A simulation over the entire quarry showed the product to be within the size range produced at Mountsorrel Quarry, and with a simulated fines content of 13%. When the CSS on the primary crusher was altered from 165.1 mm (the operating size on site) to 100.0 mm, it increased the overall percentage of fines produced by 3%, increased the power draw by 140.6 kW, but reduced the overall plant production percentage of fines by 2%. Two blasts were analysed on adjacent rock faces. They had identical blast designs, but the order of deck detonation varied; the first blast detonated the bottom deck before the top and vice versa in the second blast. For each blast, measurements of the feed PSD to the primary crusher, the number of particles that required secondary breakage on the quarry floor, acoustic levels and vibration readings were measured. No significant difference was identified between the two blasts in any of the parameters measured. In conclusion, a working model of Mountsorrel Quarry has been made in JKSimMet that has been validated against data from site and Split-Desktop has been used to simulate the primary crusher feed PSD, something that was previously unknown. The effect of reversing the order of deck detonation in a two deck blast was also analysed but with no significant difference between the two blasts found.

Aug 1, 2013

By J. D. Zhu

A numerical model for predicting microporosity formation in aluminum castings has been developed, which describes the redistribution of hydrogen between solid and liquid phases, the transport of hydrogen in liquid by diffusion and Darcy flow in the mushy zone, One of the key features of the model is that it uses a two-stage approach for porosity prediction, In the first stage, the volume fraction of porosity is calculated based on the reduced pressure, whereas, in the second stage, at fractions solid greater than the liquid encapsulation point, the fraction porosity is calculated based on the volume of liquid trapped within the continuous solid network, which is estimated using a correlation based on the Niyama parameter, The porosity model uses thermal data calculated using the commercial finite element package ABAQUSTM. The model has been applied to examine the evolution of porosity in a series of experimental samples cast using unmodified A356 in which the initial hydrogen content was varied from 0,048 to 0.137 [cc/100g], A comparison between the model predictions and the experimental measurements indicates good agreement in terms of the variation in porosity with distance from the chill and the variation resulting from initial hydrogen content.

Jan 1, 2005

By I. M. Marshall

A review of technical literature covering Canadian mining emphasizes the advancement and changes that have been made in mining practice. However, current technical publications rarely outline basic principles or state definite rules that govern profitable mine operation. it may be argued that the broad principles of mining have long a go been outlined in various handbooks, text-books, and periodicals, and that these principles never alter. This is in great part true, but modern machinery, improved meta1-lurgical practice, and other advances, have in part modified these principles or changed the manner of their application. Many engineers hesitate to state specific rules, because it is so easy to quote an exception to a rules that any such statement appears to lose weight upon its very utterance. The exception to rules, and the reluctance to formulate rules, has forced such maxims as "the only rule in mining is the point of a pick," and "gold is where you find it". As an illustration of rules and their exceptions, one might quote the time-honoured maxim that a mill should not be built before a shaft has been sunk on a property in point of fact, Canadian mining history is replete with examples of wasted capital where a mill was built before a shaft had been bottomed. Y et this past year has seen a property enter profitable production whereon the building of the mill was started before the shaft was sunk. Instances such as this should not be accepted as evidence that a rule has been overthrown, but rather as an exception to the rule. The case cited pays tribute to the application of the diamond-drill combined with the correlation of sound geology. Incidentally, both these features emphasize a modern trend in the development of Canadian mining properties-a trend that is perhaps worthy of further comment. It is such trends that affect the principles of mining or modify their application. It is with such that this paper deals, at ]east in part. It is hoped that the statement of principles and the opinions herein outlined will be of sufficient interest to arouse discussion.

Jan 1, 1939

By Pierre C. Vieillescazes

MIGA: Unique Multilateral Risk Mitigator ?A World Bank Group agency established in 1988 to promote and facilitate sustainable foreign direct investment in emerging coufacilitate countries ntries (north(north--south and southsouth south--south) ?Guarantees equity and debt and many other types of investments against non-commercial risk. ?Can cover the following type of risks: ?Expropriation ?Breach of Contract ?Currency Transfer and Inconvertibility ?War and Civil Disturbance ?Non-Honoring of Sovereign Financial Obligations

May 1, 2010

By L. Sun

A numerical model has been developed to study the air flow in the flow plate and gas diffusion layer assembly on the cathode side of a PEM fuel cell. The flow plate in this type of fuel cell often has serpentine channels and the porous layer is adjacent to the flow plate to diffuse the air to the catalyst layer. Flow cross-over of air through the porous diffusion layer from one part of the channel to another can occur. This flow cross¬over is a result of the pressure differences between different parts of the channel, and it causes the flow rate through the channel to vary with the distance along the channel. A numerical study of pressure distribution and flow cross-over through the gas diffusion layer (GDL) in PEMFC flow field using a serpentine channel system has therefore been undertaken to compare the cases of a single channel and two parallel channels, with the channels having a trapezoidal cross-sectional shape. The purpose of the present work was to study the effect of the flow plate geometry on the basic fluid flow through the plate. The flow here has been assumed to be three-dimensional, steady, incompressible, isothermal and single-phase. The flow through the porous diffusion layer has been described using the Darcy model. The dimensionless governing equations have been solved by using the commercial CFD solver, FIDAP. From the results obtained, it can be found that the single channel systems have greater maximum flow rate difference than the parallel channel systems under the conditions considered in the present study. Also, the size ratio R of trapezoidal cross-sectional shape has a significant effect on the flow cross-over and pressure variation in the flow field.

Jan 1, 2005

By C. A. Pickles

Nickeliferous limonitic laterite ores contain considerable free moisture. In this research, the application of microwave radiation for the drying of this ore was investigated. The effects of sample mass, initial moisture content and porosity on the microwave drying rate were studied and the results were compared to those obtained with conventional drying. Microwave drying rates of two to three times the conventional values were achieved. Further enhancement of the microwave drying rate was realized by increasing the flow rate of air over the sample or by operating at reduced pressure. The high microwave drying rates were attributed to the inverted temperature gradient which resulted in internal heating and boiling and this in turn promoted movement of the water, both as liquid and vapour, to the surface.

Jan 1, 2005

By N. Saracoglu, J. P. Golightly, R. H. Wallis, J. J. Brummer

"The McClean uranium deposits are located 11 km west northwest of the Rabbit Lake Mine. Their average grade is 1.8 % U3O8 , and they contain 6. 350 tonnes of uranium oxide in seven pods of variable grade and mineral assemblage. They are hosted by both basal Athabasca Group and the regolith developed on the underlying crystalline basement. The major mineral facies are: sulphide, arsenide, 'bleached', and hematite, with the important uranium minerals being coffinite, uraninite and pitchblende. Abundances of carbon and sulphur isotopes are consistent with their derivation from pyritic graphite in basement gneisses. Isotopes of oxygen and hydrogen suggest equilibration at temperatures of about 200°C. Ar39/ Ar40 age determination of illite associated with ore suggest mineralization began about 1300 m.y. ago and that significant alteration had ceased by about 1170 m.y. ago though Pb/ U data suggest the deposits continued to evolve into the Mesozoic.IntroductionThe McClean deposits lie on the eastern side of the Athabasca Basin of northern Saskatchewan where they are part of a cluster of uranium deposits lying west of Wollaston Lake (Fig. 1). The general stratigraphy is schematically portrayed in Figure 2 which emphasizes that mineralization is hosted by both the Athabasca Group and the underlying regolith and also that the deposits are preserved at depth and have not suffered from preand post-Pleistocene weathering and erosion. This circumstance, combined with their simple shape and the presence of seven separate zones of mineralization (pods) allows a description, based on over 450 fully cored drill holes, to be made of the wide variation in chemistry, grade, alteration patterns and position relative to the sub-Athabasca Group unconformity. Ar39 / Ar40 age determinations have been made of illites associated with regolith, Athabasca Group and mineralization and studies are in progress on C, S, 0 and H isotopes of mineralized material and host rocks. Only some of these data have been published; Brummer et al., (1981); Golightly et al., (1982); Bray et al., (1982); and Saracoglu et al., (1983). The only other published data on McClean geology are by Tremblay (1982, 1983)."

Jan 1, 1986

By A. C. Ter-Oganesyants, N. N. Anisimova, G. P. Kotukhova, G. N. Dylko

The process utilized at Norilsk Nickel Polar Circle Division for treating slimes from the electrorefining of copper and nickel was developed in the late nineteen fifties and has survived without any fundamental changes. This technology is a combination of pyro and hydrometallurgical operations to produce PGM concentrates that are sent away for refining. The characteristic feature of the current technology is multiple-stage, extended cycle treatment with significant incomplete production, low labour and automation efficiency and poor hygiene and sanitary conditions. To eliminate all negative aspects mentioned above, specialists of Norilsk Nickel Polar Circle Division have developed a new hydrometallurgical process for treating electrolytic slimes. The main steps of the flow sheet developed are autoclave leaching of the slimes and electrochemical opening-up of a cake from autoclave leaching. The implementation of the new process will allow Norilsk Nickel Polar Circle Division to shorten the process cycle 4-5-fold thus reducing the volume of incomplete production, considerably increase labour efficiency, simultaneously improving working conditions, upgrade the final concentrate, reducing costs and increasing PGM recovery during refining and, ensure higher security of precious metals by employing automated processes and vacuum sealed units.

Jan 1, 2004

By Hasini Wijayaratne

Anode cover material, a mixture of crushed electrolyte and alumina, is a crucial part of an aluminium reduction cell because of its important role in maintaining overall heat balance. However, until recently little attention has been given to understanding or controlling its composition and quality. The thermal conductivity of anode cover material determines the extent of the heat loss from the top of the cell. This will change as a function of the granulometry and composition of the applied cover as well as over time as the cover material consolidates on top of the cell. The ability to measure or predict the thermal conductivity of fresh and ageing cover is an important tool for managing cell heat balance. Recent studies have shown that granulometry or more correctly, voidage is likely to be the predominant determinant of thermal conductivity of anode cover materials. We have developed equipment to measure the thermal conductivity of granular cover material and tested the relative importance of composition (ratio of alumina to crushed electrolyte) and granulometry/voidage on cover thermal conductivity. In general, our results confirm that granulometry is the dominating factor. Generally, high voidages contribute to lowering the thermal conductivity especially when particles are mostly fine. However the relationships between granulometry, voidage and thermal conductivity are complex due to the varying nature of heat transfer between particles. Aging of granular cover material occur during cell operation forming a consolidated crust due to exposure to heat and fumes over time. Structure and thermal behaviour of this consolidated crust is also important in understanding the overall properties of cover. This paper presents the outcomes of laboratory studies conducted in order to understand the thermochemical behaviour of anode cover material and in particular, the role of fines in anode covers mixtures.

Jan 1, 2011

By Ruan Chi, Zhenyue Zhang, Zhengyan He

In order to understand what governs the leaching of exchangeable rare earth (RE) and impurities and enhance the RE leaching process, the effects of the concentration of ammonium sulfate, pH and leaching temperature on the migration of RE and aluminum (Al) during the leaching of weathered crust elution-deposited rare earth ore was studied. The elution curves for ammonium ion (NH4 +) were also studied to reduce the consumption of the leaching agent. It was found that a high concentration of leaching agent can enhance the leaching process of RE and Al, reduce the breakthrough volume of NH4 + and more rapidly obtain the equilibrium of NH4 +. However, excessive leaching agent can both increase the cost and the burden on the environment. There is almost no variation on the elution curves of RE and Al in the pH range of 4-8 and control of the pH of the leaching agent can be omitted. It is better for the leaching work to be done in summer since higher temperatures can enhance the RE leaching process and improve the use ratio of ammonium. Using 0.1 mol/L ammonium sulfate for leaching 250 g RE ore, 95.42% RE extraction can be obtained when the volume of leachate is 102.6 mL. At this moment, only 18.17% of NH4 + is used to exchange RE and 49.22% of NH4 + is left in the leachate that can be reused as leaching agent by replenishing ammonium sulfate. The results of our studies can provide theoretical guidance for high efficiency and low consumption exploitation of RE ores.

Jan 1, 2016

By A. Burduk

The traditional approach to managing information flow between a mine underground and overground, applied in copper mines of KGHM Polska Miedz S.A., is mostly based on exchanging spoken information using the mine telephone network and printed documentation. This way of information flow significantly influences effective use of time of a shift foreman employed at a mining division. In order to minimise multiplication of significant information generated as paper documentation, a concept of an IT system module to input basic data concerning operation of the mining division was developed. The idea is based on computer software that permits inputting data in the underground and their immediate sending to the overground. The above-mentioned solution will permit significant reduction of administrative work time that each foreman has to do on each shift. The time saved on filling forms and communication will permit the foreman and the other workers involved in information flow to spend more time for execution of their basic duties. In the case of the supervision employees working in the overground, the IT system will allow all the interested persons to be informed directly, with no necessity to transfer the information on the situation in the given mining division by turns from one to another. On the other hand, saving time on administrative works will permit the foreman employed in the underground executing more detailed inspection of workplaces in his subordinate mine division. Thus, availability of the foreman for the mining division operation will be improved. KEYWORDS

Aug 1, 2013

By D Martín, G. Díaz, F. Cubeddu, A. B. Mejias

The Modified ZINCEXTM Process (MZP), developed by Técnicas Reunidas, is an industrially proven flexible process. It can handle a wide range of primary and secondary raw materials, producing SHG zinc. The core of the Modified ZINCEXTM Process is the zinc solvent extraction unit. This unit is an effective barrier for any leachable impurities present in the raw material. As a result of this an ultra-pure zinc solution is always obtained. The high versatility of the process makes the application of the technology in different scenarios possible. MZP can be effectively applied when developing a whole new plant (Skorpion) or adapting its scheme to an existing refinery (Akita), in both cases giving the same results. Flexibility in terms of capacity of the plant is a great advantage of the MZP, there is the possibility to adapt the global process to a wide range of production capacities. Zinc production capacities of over 150 000 t/a may be achieved with a single solvent extraction plant train. The robustness of the Modified ZINCEXTM Process has been recently proven on two new plants currently in operation: Portovesme (Italy) and Horsehead (USA) after start up during 2013. The status of both plants is described in this paper.

Jan 1, 2014

By Nelson Lawrence

An Electrical Risk Management/Inspection Program has been designed specifically for the mining sector in order to provide electrical code expertise and systemic gaps in electrical systems. Goals include improved safety and productivity, reduced injuries and help to enable businesses to better comply with the electrical codes and regulations that govern them. The Electrical Risk Management/Inspection Program is now recognized by some of the world?s largest mining organizations. Since June, 2001 these electrical safety advisory services have been available to underground and surface mine sites throughout Ontario and are now offered throughout Canada and around the globe. This program is also currently being applied to review new electrical installations for mine construction projects thus improving the safety and reliability of mine site electrical systems.

May 1, 2006