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By V. S. Melamud, A. G. Bulaev

"Sulfide ore processing is characterized by significant losses of metals, for example, with flotation tailings. Therefore, flotation tailings can present an important source of metals. The treatment of flotation tailings is a technological issue due to low content of valuable metals (e.g. copper and zinc) and high iron content. The goal of the present work was to investigate extraction of base metals and gold from old flotation tailings containing 17% iron, 0.26% copper, 0.22% zinc, and 0.7 g/t gold. Chemical leaching in columns with 0.5 to 10% sulfuric acid solutions and bioleaching in air-lift percolators were used for the extraction of base metals. 1% H2SO4 provided high extraction of base metals and best selectivity. Recovery of copper and zinc reached 35% and 40%. Increasing H2SO4 concentration did not lead to significant increase in base metals extraction, but led to increased iron concentration in the pregnant solutions. The 1% H2SO4 leaching solid residues were used for further experiments. Acid leaching and bioleaching did not result in significant increase in base metals recovery. Leaching of the residue with 10% H2SO4 provided extraction of 4% copper and 20% zinc, and bioleaching for 100 days provided extraction of 16% copper and 12% zinc. The recovery of gold by cyanidation from the flotation tailings, the 1% H2SO4 leaching solid residue and residue of two-step acid leaching were 50, 49, and 65%, respectively. The results suggest that acid leaching can be effective approach for treatment of old flotation tailings.INTRODUCTIONAbout 80% of base metals (copper, nickel, zinc) are produced through pyrometallurgical treatment of sulfide ores. Mining and metallurgical treatments of sulfide ores are presently characterized by significant losses of non-ferrous and precious metals into the various wastes. For example, flotation of sulfidic ores yields formation sulfide flotation tailings. These wastes pose a problem not just because of their sheer volume, but some of them may affect local ecosystems. Nowadays, mining and metallurgical wastes can be considered as technogenical source of base metals."

Jan 1, 2016

By Ye Chen, Jianhua Chen, Xianhao Long, Qingxia Liu, Zhenghe Xu

"It is crucial to understand the mechanism of the collector interacting with the mineral surface in the presence of water molecules, which could influence the relaxation and electronic properties of sulphide mineral surface due to the proximity effect for narrow band gap of semiconductors. The adsorptions of three typical collector molecules (xanthate, dithiocarbamate and dithiophosphate) on the sulphide mineral surfaces in the absence and presence of water molecule have been simulated by density-functional theory (DFT). The calculated results show that the adsorptions of collectors on clean mineral surface in vacuum are not in agreement with the observed flotation behaviours. The presence of water molecules has a great influence on the adsorption of collectors. The analysis of density of states of the mineral surface atom suggests that the adsorption of water molecules could influence the electronic properties of mineral surface and consequently influence the adsorption between the surface and the collector molecule.INTRODUCTIONIn the separation of multi-metal sulphide ores, the selectivity of a collector is a key factor for the efficient recovery of the aimed mineral. Xanthate, dithiocarbamate (DTC) and dithiophosphate (DTP) are the most common collectors used in the flotation of sulfide minerals. Generally, xanthate exhibits powerful collecting property but lack of selectivity. While dithiophosphate and dithiocarbamate show the good selectivity in the lead and copper sulphide mineral flotation. The mechanisms of these collectors interacting with the sulphide mineral had been attracted many attentions and several mechanism based on experimental results had been reported (Chander & Fuerstenau, 1974; Fuerstenau, 1990; Raju & Forsling, 1991; Crozier, 1991; Bradshaw, Cruywagen & O’Connor, 1995; Guler, Hicyilmaz, Gokagac & Emekci, 2006). However, the micro-mechanisms of the selectivity of these three thiol collectors on different sulphide mineral surfaces are not fully understood."

Jan 1, 2016

By A. Vien, A. J. Neale, B. C. Flintoff, R. P. Edwards

Froth flotation is one of the most widely used and effective processes for mineral beneficiation. First introduced in 1911, flotation technology has seen many developments over the past 80+ years. Innovations in reagent chemistry, equipment design, process analysis and process control have given design and plant engineers a powerful set of "tools" for process optimization. However, it does not follow that all flotation systems are optimized. As Klimpel observes: "The problem with the industrial flotation process is that it is relatively easy to get reasonable results, and relatively difficult to get excellent results" Klimpel (I 988). While reasonable was sufficient in the past, competitive forces will make excellent necessary in the future. Judging by the activities in many Canadian plants this transition is already underway. This paper examines the role of some of the optimization "tools" in effecting this change.

Jan 1, 1994

By H. Mindivan

In the present study, the feasibility of recycling AA6061 Al alloy chips by a combination of ciyomilling, cold compaction and hot extrusion processes was investigated. Furthermore, the effect of Al powder addition to the recycled Al alloys chips on the mechanical properties was investigated. The characterization of recycled Al alloys was made by structural examination and mechanical tests (hardness, compression and dry sliding wear tests). The results indicated that by increasing wt. % of Al powder added to the recycled Al alloy chips the studied properties (the density, hardness, compressive strength and wear resistance) increased due to reduction of porosity in the recycled Al alloys.

Jan 1, 2011

By P. Srinivasan

Corrosion is a major operational problem in amine-treating plants causing significant expenditures each year, Corrosion may become more severe when the amine plants contain process contaminants ? namely heat-stable salts. The heat-stable salts enter the plants with feed-gas streams and makeup-solution, and/or are produced within the plants by reactions of alkanolamine and available carboxylic-acid anions, This work investigated interaction corrosion effects that may exist in amine-treating plants containing a mixture of heat-stable salts, The investigation was experimentally carried out in a 5 kmol/m3 monoethanolamine (MEA) solution containing 0,20 mol/mol carbon dioxide (CO2) loading at 80°C under atmospheric pressure using carbon steel 1018, Six heat-stable salts, including formate, oxalate, bicine, acetate, thiosulfate and chloride, were tested with a series of salt combinations, Potentiodynamic Polarization, Tafel Extrapolation, and Cyclic Polarization were used for revealing corrosion behavior, determining corrosion rate, and examining the pitting tendency, respectively, Results show that thiosulfate induces the most corrosive environment when present either individually or in the form of salt mixtures.

Jan 1, 2005

By S. Aram

Concrete reinforcing requires coordination among many roles: structural engineer, estimator, detailer, fabricator, installer and others. The methods used to define and represent concrete reinforcement elements and assemblies in building information models is crucial in determining the efficiency of sharing data among BIM platforms and the effectiveness of using the carried data in production planning, fabrication and site work activities. Starting from the information items that are required to be provided by BIM platforms, as defined in earlier work, we have developed the Industry Foundation Classes (IFC) bound Concepts and Model View Definitions (MVDs) for concrete reinforcement. Furthermore, in coordination with software developers, we propose guidelines for best practices for concrete reinforcement modeling. Implementing these guidelines by software providers will improve reinforcement modeling with regard to various aspects of reinforcement products like geometric representation, placement, and property specifications. The proposed approach is selected as a way to improve functionality of the shared data for production planning, fabrication, project management, and site activities. Guidelines for assigning information to rebar type and instance definitions as well as to rebar elements and assemblies are provided. An efficient method of sharing geometry and property sets among rebar instances of a rebar array is also defined.

Aug 1, 2013

By Mark Liskowich

When is it the proper time to initiate engagement with various stakeholders, including Indigenous communities? This paper will demonstrate what stage of a project’s evolution is the appropriate time to initiate a stakeholder engagement plan. It will look at aspects to consider when identifying the communities to involve. It will describe the contents of a Stakeholder Engagement Management Plan as well and touch on how tried and true options analyses, such as a Multiple Accounts Analysis can be used to inform the results of the engagement, guide the development of your project and clearly document the engagement process. It will illustrate the benefits of initiating engagement at the appropriate point in your project’s schedule, and the limitations of doing so too early and at later stages of the project engineering. The benefits of this approach can be realized within any legislative Jurisdiction including the Canadian Environmental Assessment Act 2012 and Canada’s new Impact Assessment Act.

Jan 1, 2020

By Xiu-Xiang Tao

This study investigated bio-liquefaction of lignite and its model compounds of thymol, bezioc acid and quinoline by a fungus, Hypocrea lixii AH. It analyzed, during bio-liquefaction, enzyme activity of oxidase, LiP, Lac, MnP and polyphenol oxidase, and degradation products by UV-Vis, FTIR, 13C NMR and GC-MS. The results showed that the bio-liquefaction percentage (by mass) of lignite was up to 44.86 %. The bio-liquefaction products of lignite were mainly aniline, amide, ether, carboxylic acid ketone and ester. The aromatic ring number was 1-3 with an aromatic carbon ratio of 0.328, which indicated rings opening, bonds breaking and oxidation reaction. By considering with the enzyme activity analysis results, it showed that LiP and Lac catalyzed reactions to open aromatic cycles and to break bonds; esterase to break ester bond; and peroxidase in oxidation reaction.

Aug 1, 2013

By Peter Cunningham

Teck Facts and Figures ? Employ more than 14,000 around the world, includes: ? Over 8,600 in Canada (close to 7,800 in British Columbia) ? Close to 2,000 in Chile ? Over 2,700 in Peru ? Approximately 600 in U.S. ? Hundreds more in exploration around the world ? Total capital expenditures ? $1.8 billion for 2012

Aug 1, 2013

In 2009 Newmont Mining Corporation?s annual global spend on grinding media reached $94M USD, having doubled in the five years since 2004. The major contributing factor to the spend escalation during this period was unit consumable price, with total media consumption also rising as a function of annual ore tonnes milled. In an effort to better understand and manage the growth of this expenditure a significant supply chain management program was implemented. This was complemented by a series of technical initiatives focussed on grinding media specifications, quality management and the prediction of grinding media wear rate as a function of physical ore characteristics. This paper discusses the methodology and outcomes of these activities.

Jan 1, 2012

By Abhilash

Uranium is conventionally extracted using a process that employs strong acid (H2SO4) and an oxidant (MnO2) as leaching agents. This method often creates environmental problems, requires large amounts of energy, and involves a complex operational plant. It is not, however, economically attractive to extract uranium from low-grade ores by chemical leaching. Because the content of U3O8 in the Indian ore is usually below 0.1% by weight, it is necessary to develop an alternative process to enable the efficient and economic recovery of uranium. Uranium ore from the Narwapahar mines, UCIL is a type of vein deposit found in India, which accounts for ~54% in India. The ore (0.047% U3O8), though of Singhbhum area, possess exceptionally different mineralogy due to presence of some refractory minerals and richness of apatite (5%) resulting in a maximum 78% recovery through conventional processing at UCIL, with a very high consumption of sulfuric acid and pyrolusite, besides possible loss of uranium as uranium phosphate. To avoid usage of environmentally non-benign oxidants, remediation of influence of phosphates, and improve the overall process output of uranium; an alternate extraction technology using microbial isolate(s) is worthwhile exploring and the same is presented in the paper. The microbial isolate enriched with Acidithiobacillus ferrooxidans grown from source mine water was employed for bio-leaching of uranium while varying pH, pulp density (PD), particle size, etc. On varying pH at 35oC using 20%(w/v) PD and <75µm particle size, 83.5% and 78% uranium bio-recovery were observed at 1.7 and 2.0 pH in 40 days against maximum recovery of 46% and 41% metal in control experiments respectively. Whereas, it was observed that grinding of ore to finer size actually helped dissolution of uranium. Finer size particles (<45µm) gave a maximum biorecovery of 93% in 40days at 10%(w/v) PD, 1.7 pH and 35oC. The bio-recovery of uranium fell down from 93% to 82.73% and 60% on increasing the pulp density from 10% to 20% and 30% respectively for particles of <45µm size. The higher uranium dissolution during bioleaching at 1.7pH can be correlated with increase in redox potential from 433 mV to 664mV in 40 days.

Aug 1, 2010

By A. H. Onur, S. Ural

"The Afsin-Elbistan coal deposit with its 3.4 billion metric tons of reserve is the biggest coal basin and one of the most important resources for electrical energy production in Turkey. The coal deposit is located north of Elbistan, Kahramanmaras Province, in southeast Turkey (Fig. 1).The Kislakoy sub-basin of the Afsin-Elbistan basin was selected as the first open cast mine to feed four power station blocks of 340 MW each. The mine is equipped with six identical bucket wheel excavators of the type Sch Rs (2300/5) 32. The annual coal demand of the power station is 18.5 million metric tons. The Elbistan basin encompasses an area of 900 km2, and its centre lies about 1150 m above mean sea level. The sedimentation took place mainly in the upper Pliocene period. The thickness of the coal bed varies from 20 m to 60 m, respectively. The basal part of the coal beds consists of clay, marl and sandy clay. These formations are overlain by gyttja, which may also occur in the form of calcareous ooze, enveloping coal beds. The thickness of the gyttja is up to 35 m (Otto-Gold, 1969). The coal of Afsin-Elbistan is soft coal and the quality has been found to vary considerably throughout the deposit. The thicknesses of the sterile intercalations vary from 0.50 m to 2.2 m and average 1 m in thickness. From the quality control point of view, the coal seam is regarded as upper seam where the gyttja formation occurs as sterile intercalations, and lower seam where the clay formation occurs instead of the gyttja (Fig. 2). The CaO content of upper Kislakoy coal is very high, grinding resistance is low and base to acid ratio of ash, that is, the ratio of acid oxides of metals to base, is greater than one (Ural and Onur, 2001). Contrary to upper Kislakoy coal, CaO content of lower Kislakoy coal is very low, grinding resistance is high and base:acid ratio of ash is smaller than one. Modified Impact Strength Index (MISI) tests are used to determine the grindability of the Elbistan coals (Ural, 1999)."

Jan 1, 2003

By Nobuyoshi Yabuki

Building Information Modeling is a prevailing methodology in the building industry and half (by length) of the world&apos;s shield tunnels are in Japan. Accordingly, for shield tunnels from 2005 to 2007, we developed a product model called IFC-ShieldTunnel, which is based on Industry Foundation Classes (IFC), in order to meet the future demand for such a product model. IFC-ShieldTunnel was developed by adding new elements that are specific to shield tunnels and that are not included in the original IFC. The added elements include shafts, segments (A, B, and K types), waterproofing elements, segment joint elements, and ring joint elements. Furthermore, soil layers and void elements were created. Recently, we updated the product model by re-organizing the entities and correcting errors. We deployed the updated IFCShieldTunnel model in the construction of an actual shield tunnel in Tokyo for about a year from August 2010 in order to check its feasibility. In the verification process, first, segments were modeled using Autodesk Revit Structure 2011 and property data were assigned to each segment element. Next, a mapping between the original attributes of the entities of IFC and properties of IFC-ShieldTunnel segments was developed. Using this mapping and IFC?s IfcBuildingElementProxy function, we were able to convert the IFC data from Revit Structure 2011 to IFC-ShieldTunnel automatically. Segment data were also converted from Revit Structure to Google SketchUp by IFC-ShieldTunnel. Furthermore, the construction scheduling and cost data were converted from Revit Structure to EXCEL for 4D and 5D analyses of construction. We interviewed engineers who used IFC-ShieldTunnel and received positive comments about the utilization of the product model. Overall, our test demonstrated the feasibility of IFC-ShieldTunnel. In future work, we plan to apply IFC-ShieldTunnel to more projects and test its practicality.

Aug 1, 2013

By P. Hajiani

"It has been shown that the economics of the hydrometallurgy of a rare earth process depend upon the amount of acid needed to extract the metal per unit mass of the ore. In this paper, we show how to save a significant amount of acid treating a low grade ferrocarbonatite and extracting +99% constituent REEs. In order to save the acid, the alkali earth metals, originated from gangue minerals were removed prior to REE leaching. Moreover, the operating conditions of leaching reactor are optimized to leave iron behind and to leach REE selectively and effectively. Consequently, the hydrochloric acid consumption per ton of ore drops significantly compared to other processes.INTRODUCTIONThe viability of an extractive metallurgy process of rare earth elements (REEs) to produce an intermediate mixed concentrate depends upon a low-cost simple flowsheet (Bogner, 2014). It has been known that regardless of the mineral, the acid consumption is intimately associated with the operational cost (OPEX) of any REE project, particularly when the initial REE grade is low. Besides acid, the other reagents consumed in the process impact the OPEX. This makes minimizing acid consumption in an REE method a critical priority. The acid consumption in different projects has been reported to be equivalent of 100 kg to 1000 kg HCl (100%) per tonne of ore (Average: 500 kg/t HCl 100%) (Bogner, 2014). This value is strongly correlated with the grade of REE in the ore and therefore in the pre-concentrate.Previously, it has been stated that the Montviel flotation concentrate requires about 300 kg HCl (100%)/t ore to attain +99% REE recoveries using direct leaching (Yu, Verbaan, Pearse and Britt 2013). Hence, for an ore feed rate of 2500 t/d ROM, a large acid production plant (744 t/d HCl 100%) would be required for acid leaching of such concentrate. The equivalent Chlor-alkali plant is estimated to cost M$ 150 (CAPEX) and may require 100 MW power. Therefore, there is a necessity to improve the extractive hydrometallurgy and to reduce the acid consumption significantly."

Jan 1, 2016

By N. Giguère

Until recently, the heat treatment of pressure die cast parts has always been considered unpractical because the solution heat treatment resulted in unacceptable blistered parts. This was due to the presence of massive porosity associated with the die casting process where the inflow of metal inside the mold cavity is extremely turbulent. With the steady improvement of foundry practices and the generalization of vacuum die casting, porosity defects have been reduced to the point that a partial solutionizing heat treatment can be applied without any damage to the casting. However the solutionizing temperature must be lower than that applied to macroporosity free castings and for much shorter time. The object of the present study was to determine the optimum solutionizing temperature that can be applied to aluminum 383 die cast brackets along with the optimal temperature and time of aging resulting in the highest improvement in mechanical properties (both strength and ductility). This was done by testing strength and deformation on the casting itself using a specially designed jig; the crushing force to deformation curve was analyzed so as to quantify the improvement in both strength and ductility gained with the partial precipitation hardening heat treatment.

Jan 1, 2011

By C. Blawert

The corrosion properties of the skin and the bulk of semi-solid processed and high pressure die cast AZ91 alloy were studied in 5% NaCI solution by (a) analysing the corrosion morphology, (b) measuring electrochemical polarization curves, (c) performing electrochemical impedance spectroscopic measurements, and (d) immersion tests at constant pH-values. Using XRD, LM, SEM and EDX to evaluate the microstructure of skin and bulk specimens, the corrosion results were related to the microstructures of the particular alloys. However, microstructure and corrosion performance were found to be similar for both production processes, and only slight but distinct differences were found. Generally, the skin corrosion properties are inferior to those of the bulk, with the exception of the high pressure die cast AZ91 alloy, where the finer microstructure of the skin layer exhibits a better performance as showed by impedance studies and confirmed in long term immersion tests.

Jan 1, 2004

By Fathi Habashi, Michel Pagé, Farouk T. Awadalla

"Chrysotile asbestos can be dyed with certain dyestuffs to form stable coloured products whose hemolytic and cytotoxicity are greatly reduced. Examples of these dyes are Thiazol Yellow G (a monazo dye) and Trypan Blue (a diazo dye). Other dye stuffs, for example, basic dyes with triphenyl methane structure, Brilliant Yellow (a diazo dye), and Methylene Blue (a thiazine dye) colour asbestos but do not reduce its toxicity. Similarly alizarin, 8-hydroxyquinoline, and representative members of the phthalein group Bromocresol Purple and Phenolphthalein.IntroductionThere is, at present, a controversy regarding the dangers of asbestos fibres, and attempts are being made to render it less toxic. One of these attempts consisted of treating chrysotile asbestos with gaseous phosphorus oxychloride, POCI], at ambient temperature and in absence of moisture. The product had to be heated at 300°C to 500°C to expel exess entrained reagent to get a material containing 0.5070 to 5% phosphate groups and known as Chrysophosphate (Lalancette and Dunnigan, 1982). This product showed decreased toxicity as measured by its hemolytic effect on red blood cells (fable 1). In another approach, Flowers (1983) showed that when chrysotile asbestos was thoroughly mixed with a solution of ferric ammonium sulphate and the slurry was then filtered and dried, the product showed a marked decrease in cytotoxicity.In the present investigation the problem of toxicity was considered from a different point-of-view. Chrysotile asbestos is a hydrated magnesium silicate that can be represented by the structural model shown in Figure 1 from which it can be seen that magnesium hydroxide groups, Mg(OH)2, form a part of the silicate structure. Certain organic reagents that are known to react with magnesium ion in solution to form chelates were reacted with asbestos to find out whether a chelate was also formed on the fibres, and if so , what will be the hemolytic action and cytotoxicity of the product."

Jan 1, 1991

By J. M. Goris

"Researchers at the U.S. Bureau of Mines are conducting research on cable-type ground supports to assess their material and support properties and to provide design criteria for implementing cable supports as a workable roof control system under various underground mining conditions. Much of this work involves laboratory assessment of the material and support properties of cable supports using both conventional and birdcage steel cables. Included in this assessment are single and double cables, effects of changes in embedment length on support strengths, water-cement ratios, use of breather tubes, and pumpability and water-bleeding properties of grouts.IntroductionSince cable supports were introduced in the early 1970s, considerable research has been conducted in laboratories and at mine sites to understand their behaviour. The U.S. Bureau of Mines began a laboratory evaluation project in 1985 at the Spokane Research Center (SRC) to study the behaviour of cables supports under uniaxial loads so that the effects of various cable support components, such as grout and breather tubes, could be identified. Other objectives were to compare the behaviour of various types of cables and grouts and to collect meaningful data for numerical analyses. Pull tests were conducted to determine how cables supports reacted under uniaxial loads and how they failed when ultimate loads were exceeded. Such data are essential for the development of numerical models for analyzing rock mass behaviour when the rock is supported with cables.Test ProgramBecause each cable support can be composed of either single or double cables as well as a breather tube, pull tests were designed to include a variety of samples containing these components. A series of samples containing a single conventional cable, a neat cement grout having a water-cement ratio of 0.45, and no chemical additives was selected as a standard (Table I). Then one component in the system, such as the presence of a breather tube, was changed, and results of tests compared to results obtained for the standard samples to determine what influence that component might have on the behaviour of the support system. If significant changes in test data occurred, they could be attributed to that one component. To control the quality of the samples, the physical condition of the cables and tubes were monitored closely, and compressive and tensile strengths as well as flow properties were determined for the grout used in each test series."

Jan 1, 1991

By L. Cheng, Y. W. Pan, Y. R. Liu

"Impounding deformation of slope and foundation is significant during and post dam construction. Reservoir impoundment is accompanied with various phenomena, including material degradation, effective stress decreasing and buoyancy in rock masses. These phenomena are related with some engineering concerns like reservoir-induced earthquake, landslide and dam stability. The Malpasset dam and Vajont dam are typical hydraulic projects suffering from seepage in dam foundation and slope, which finally led to failure and landslide. Pore pressure in jointed rock masses is considered in constitutive relation. The expression of effective stress for porous rock with fluids is incorporated into the Drucker-Prager criterion. Based on monitoring data of valley width and dam deformation, the effective stress law is applied to analyse the impounding influence of slope and foundation to Jinping-I high arch dam. The dam is accompanied with complicated topographical and geological conditions. The results show that calculated and monitored values agree well, and the application of effective stress law provides an approach to evaluate dam deformation, stress and stability with impounding effect considered.INTRODUCTIONImpounding deformation of slope and foundation is a common and significant problem during dam construction and operation. This phenomenon exists in a lot of reservoirs in China, like Laxiwa, Ertan, Xiluodu and Jinping-I arch dams, and some dams in Europe. It is related with some engineering concerns like reservoir-induced earthquake, landslide and dam stability. The Malpasset dam and Vajont dam are typical hydraulic projects suffering from seepage in dam foundation and slope. Monitored data indicates that the valley width tends to shrink in hydraulic engineering during the impounding process, which will change the stress and deformation of dam and abutment. Therefore, global stability of dam and foundation should be evaluated with impounding process taken into consideration."

Jan 1, 2015

By J. G. Kelly

"IntroductionOver the past twenty-five years of improvements to scooptrams In the Ontario Division of Inco Ltd., records indicate that on average, an 8 yard capacity machine at 80% availability will load, haul and dump about 100TPH from an average stoping area. This, essentially, means that Inco mines are limited to 2000 TPD as an approximate maximum production cap per minute. Some of the improvements made to scooptrams over this period have been:• dry disc and oil immersed brakes on larger loaders;• to replace air over hydraulic systems;• modulated shift transmissions;• greater breakout and tramming capacities by using larger engines and buckets;• operators&apos; compartments have been enlarged and better seats,• joystick controls and air-conditioned cabs have been utilized&apos;• major cost savings have been realized through tire maintenance improvements; and• major savings, safety improvements and increased ore recovery by using remote controls.After reciting the improvements listed above, and the list is by no means exhaustive, it is quite obvious that scooptrams are a mature product and that major design or performance improvements will not occur in the futre. Any futher improvements will be incremental in nature. Loading, hauling, and dumping with scooptrams is a batch process and as such is limited in its total output.Continuous Load/Crush/Convey Systems:In order to improve productivity, a radical new system was required. The target was 2000 tons per shift. In 1984, to meet the goal, Inco acquired the rights to a contiunous loader from Canadian Mine Services. Inco made modifications to the original prototype machine, such as: (I) conversion from rail mounted to crawlers for increased mobility; (2) a hydraulic cooling system was added; (3) flight bars were changed from cast to forged; (4) motor horsepower increased to 200 hp from 150 hp. Emerging from these modifications came a machine known as the CL-looo Oscilloader (Fig. 1).The CL-looo Oscilloader is an electric hydraulic 35-ton machine which is crawler mounted and has a drawbar pull of 30 tons. It has an adjustable frequency, oscillating lip which simulates the digging action of a manual .shovel. This action agitates and lifts the muckpile enough to allow it to settle by gravity onto the chain and flight conveyor table which then removes the ore to the tail end for discharge into either a crusher, a conveyor, a truck, or a combination of these.Late in 1985, six oscilloaders were fabricated and put into Inco mines for field trials. At Creighton Mine some early field trials were conducted with a rail mounted continuous loader loading directly into 140 cu.ft. Granby cars. Much of the field testing was in VRM drawpoints with the Oscilloader loading into 20-ton trucks or into Teletrams . At Levack Mine, by puttmg the truck on remote control, it was possible to have the operator run the Oscilloader and load his own truck (Fig. 2). At McCreedy West Mine, Copper Cliff North Mine, and Copper Cliff South Mine, the Oscilloaders discharged directly into 26-ton trucks."

Jan 1, 1988