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By M. Leahy

"Very little is known about the large scale fluid dynamics and associated distribution of copper in an operating electrowinning cell, yet they will have a major influence on mass transfer and plating quality. The CFD model in this work is used to simulate an entire EW cell with 60 cathodes and 61 anodes, or 121 anode–cathode pairs, elucidating for the first time the three-dimensional (3D) flow and copper distribution in an industrial cell. Two methods for the distribution of electrolyte are modelled:1. Downcomer method: electrolyte is fed by a downcomer at one end of the cell, overflowing at the opposite end.2. Manifold method: a horizontal manifold pipe runs the whole length of the cell and feeds electrolyte via small holes in the top of the manifold pipe.The recirculation that develops within each anode-cathode pair, driven by oxygen bubble generation on the anode, is similar to that seen previously in two-dimensional models of single anode–cathode gaps. However a more complex 3D flow recirculation is established, which involves flow of electrolyte down the side gaps (being a path of low resistance for return flow) as well as the usual return flow down the cathode side of each pair gap. The bubble-driven flow is not influenced by the mode of electrolyte distribution.The electrolyte flow due to the manifold and downcomer is somewhat secondary to the bubble driven flow. In the case of the downcomer distribution mode, the high injection velocity causes a very turbulent flow in the first 1–2 m down the cell from the downcomer, with several large vortices developing. This may lead to some sludge particles being entrained into the bulk of the cell.In the manifold pipe case, the jet from each hole is dissipated very quickly, within the first 10–20 cm. The jets are directed into the downward flowing zone of the bubble-driven recirculation, which leads to unstable and periodic behaviour on a large spatial scale.In both the manifold and downcomer cases, there is a marked two-zone vertical stratification in copper concentration."

Jan 1, 2016

By K. Iturralde

The article discusses the possibility of automation in refurbishment processes of social dwelling built from 1950 to 1970. These massively produced buildings were mostly designed prior to the law enforcement regarding thermal insulation or accessibility. Nowadays, many of these buildings are being retrofitted. The article focuses on the works in the external envelope. The task of renewing the whole social building stock is big and it requires a systematic process that facilitates a rapid upgrading, without neglecting the specific situation of each case. How could an automatic refurbishment process of these buildings be defined? The process should start with the data collection of the building and the creation of a 3D model using software such as BIM. The project, drafted in 3D, should facilitate the manufacture of building elements by robotics. In turn, it should be noted that during the assembly at the site, the pieces must be fixed quickly and efficiently. Is it possible to implement an automated process for the refurbishment of apartments built in the second half of the twentieth century? To approach the answer, a virtual refurbishment project is performed. The article focuses on the rehabilitation of the building envelope. Furthermore, it gives special attention to the double skin facade. It is well known that a second skin in this type of building can be an element that integrates several functions. Finally, needless to say that refurbishment of residential buildings is a need in our society. By extending its life cycle, robotic refurbishment provides more favorable socioeconomic and environmental capabilities than the sole construction of new buildings.

Aug 1, 2013

By J. Arzúa, L. R. Alejano, P. Rodríguez

"After six years of successful excavation with a support pattern, some roof failures have happened in a room-and-pillar underground mine excavated in a stratified rock mass. In this paper the authors give explanation to the failure mechanisms and redesign the support in order to solve the recent problems of roof collapse.The mine magnesite bed is approximately 14 m thick, and runs in the E-W direction with an average dip of 18º. Due to mine constraints and the inexpensiveness of the ore, the excavation is performed in the mineral itself, avoiding the need for mining dumps and waste excavation. Rooms and drifts are oriented in the mineral bed to form an angle of 19º to the direction of the strata, reducing the roadway gradients to less than 10%. Rooms are 11 m wide and pillars are 7 m wide. They are designed to leave a 1 meter thick magnesite bed in the roof of the rooms to act as a supporting beam. More often than not there is a layer of very poor quality marly shale up to 1 m thick resting on this magnesite beam. Overlying the poor quality marly shale there is a better quality, self-supporting sandy shale.First, a characterization of the involved rock masses (magnesite, marly shale and sandy shale) is performed, collecting the geotechnical data from previous studies and performing new in situ geotechnical surveys to check the soundness of the previous data. A distinction is made between different quality zones inside the mine by means of the RMR classification, associated to the occurrence of faults.Back-analysis of some of the failed rooms and data from exploration boreholes were used to determine the failure mechanisms (associated to Voussoir type failure or occurrence of sub-horizontal joints crossing the magnesite beam). Based on an understanding of these mechanisms, the method used to design the support and to analyse the stability of the different possible thicknesses of the magnesite beams of the rooms and drifts of the mine were improved.Numerical models of the most relevant conditions found in the mine were performed in order to better understand the behaviour of the roofs and to simulate the supporting solution obtained in the previous analyses.The most relevant conclusions with regard to the main elements causing the instability of the roof include the appearance of sub-horizontal discontinuities crossing the magnesite bed, which causes total instability of the roof and usually leads to collapse; excessive thinness of the magnesite beam in the problematic rooms; and the relaxation of the deepest (around 270 m in depth) zone of the mine because of existing faults."

Jan 1, 2015

By Y. Jiang, B. Li, R. Liu

"In this study, laboratory flow tests were conducted on 2-D artificial rock fracture network models containing a single intersection constituted by two inlet and two outlet branches. Three models with different intersecting angles of 60°, 90° and 120° were tested using both dye solution and distilled water. Constant flow rates were imposed on one inlet, and the flow patterns in the fracture intersections were captured by using a CCD camera. The test results were compared with the predictions made by numerical simulations that solved the Navier-Stokes equations. The results revealed that when Reynolds number (Re) is as low as less than 1, the intersecting angle has negligible influence on the flow rate of each branch and the flow patterns within a fracture intersection. As the interesting angle ? and Re (e.g., from 10 to 200) change, the normalized flow rates of different outlet branches change significantly, due to the inertial effect of fluid flow. These changes could be represented by a series of mathematical expressions involving Re and ?, which could be applied to fracture network models to improve their prediction accuracy on hydraulic properties (e.g., permeability and breakthrough curves of particles) of rock masses. INTRODUCTIONCoupled stress, flow, heat and mass transport are the corner stone subjects for many geoscience and geo-engineering disciplines, such as geological disposal of radioactive waste and geothermal energy exploitation. Many outstanding issues need to be investigated to enhance the knowledge on these subjects, and specifically more in-depth research in testing and modeling of the fluid flow in fractured rock masses is needed. In recent years, discrete fracture network (DFN) models have been extensively used to study the fluid flow and mass transport behaviors of fractured rock masses (e.g., Min et al., 2004; Zhao et al., 2011). In these models, each fracture is usually represented by a parallel-plate model, in which fluid flow exactly follows the cubic law. Therefore, comparative flow rate in each outlet branch of an intersection in these models only depends on its aperture. In reality, due to the surface roughness of fractures, the magnitude of mechanical aperture is usually larger than that of the hydraulic aperture of each fracture (Li et al., 2008; Xiong et al., 2011), and abundant flow patterns could exist in an intersection, influenced by its geometry, varying with changing Reynolds number (Re) (Kosakoswski & Berkowitz, 1999). Recent studies have also revealed that different mixing patterns might exist at a fracture intersection, bounded between streamline routing model and complete mixing model, that determine the final distribution of solutes in fractured rock masses (Johnson and Brown, 2001; Park et al., 2001). Numerical simulation has been the principal method adopted in previous studies, and the studies conducting flow tests on intersected fractures are less reported (Wilson & Witherspoon, 1976; Johnson and Brown, 2001). In this study, laboratory flow tests and numerical simulations by solving the Navier-Stokes equations were conducted on 2-D models containing a single intersection constituted by two inlet and two outlet branches, intersected at different angles. The main objective is to study the influence of intersecting angle on the flow behavior of the intersected fractures and the variations of flow patterns and fluid redistribution in each model along with the changes of the Re and the intersecting angle ?. The influence of surface roughness was not considered."

Jan 1, 2015

By J. L. Bowlby

OWING to the pressure of routine analyses at the laboratory during the past year, work of an investigational nature on water problems has been greatly curtailed. Favourable reports by the boiler inspectors indicate that the operators are giving satisfactory attention to feed-water treatment at the several . power plants. Some of the operators prefer lime and soda, others the phosphate and soda treatment. Springhill is still on the same commercial treatment as they were using last year, and satisfactory results are being obtained. This individual preference for a particular treatment, although it may be different for feed waters of similar nature, indicates that so long as proper conditions of alkalinity and concentration are maintained within the boiler, it is immaterial what chemicals are used in the treatment. This statement refers, of course, to the low-pressure boilers. In high-pressure boilers, a treatment such as lime and soda cannot be satisfactorily employed, on account of the precipitated calcium carbonate unduly increasing the amount of suspended matter. Only one case of impending trouble was reported during the year. That was at Seaboard, shortly after the new unit was placed in operation. Dissolved oxygen, considerably in excess of the permissible 0.030 cubic centimeters per liter, was detected at various points on the feed line. It was suspected that a de-aerating heater was being operated at too low a temperature, and chemical tests, made before and after the necessary adjustments, proved that this was the source of the trouble. While it has been impossible to give mine waters the attention they require, progress can be reported in the work carried out by the Mechanical Department. Past investigation of the action of mine water on various acid-resisting alloys is now bearing fruit, and it can safely be said that repair work on mine pumps has been reduced by nearly one-half.

Jan 1, 1938

"Geoscan is used for multi-elemental analysis of conveyed bulk materials in the minerals industry with proven performance and demonstrated paybacks of weeks or months in iron ore, manganese, copper, zinc-lead and phosphate industries. Geoscan-M measures continuously through the full bed depth and is unaffected by belt speed, particle size, layering, mineralogy and dust levels. Increments of typically two minutes are accurately measured and provide the plant operators with tonnage weighted results of contained elements. Measurement of the composition in real time enables prompt feedback to the mining operators and also feed forward to the process operators. Crushed ore increments can be diverted based on composition, such as diverting waste for disposal or marginal material to a stockpile for separate processing. Bulk sorting allows material to be placed into relevant stockpiles for subsequent blending to achieve consistency for process feed. Parameters used for decisions may be primary metal content, deleterious component content, other process parameter, or a combination of these. Process parameter may be the elemental ratio between critical components, e.g. Cu:S ratio, basicity, or the content of an “indicator” element (such as Si indicating material hardness). Benefits will be discussed based on case studies in copper and iron ore.IntroductionAs operators of process plants strive to remain competitive as capital and operating costs increase and commodity prices fluctuate, more focus has been directed at incremental performance improvements at incremental cost rather than major expansions to increase output. The philosophy of working smarter allows plants to adopt technologies proven in other industry sectors to minimise risk. This paper discusses one such technology that the minerals sector is adopting and has found to be safe, reliable and accurate with paybacks of weeks in most applications. New applications continue to be found and major benefits realised at various stages in the processing and handling of ores and products."

Jan 1, 2016

By A. Y. Senchenko, S. G. Rybkin, A. V. Aksenov

In gravity processing of gold-containing ore the target produced concentrate which is high gold grade primary concentrate contains a significant amount of cassiterite (SnO2). The plant attempts aiming at concentrate processing using a standard pyrometallurgical technology did not provide any positive results. The present paper is dedicated to development and testing of improved technology for pyrometallurgical processing of rich gold primary concentrate with high cassiterite content. According to material composition study primary concentrates produced at the plant contained 1.5–2.0% Au, 0.1–0.3% Ag, 55–65% SnO2, 20–25% Fe2O3, and 10–15% Fe3O4. The developed technology included alkaline nodulizing of primary concentrate mixed with sodium hydroxide and carbonate at 350–650°? with cake production. In blend nodulizing stannum and iron passed into sodium stannate (Na2SnO3) and sodium ferrate (NaFeO2) respectively. The blend of cake and fluxing agents was smelted at 1,150–1,200°? resulting in dore gold and slag production. Sodium stannate with 360°? melting point is well dissolved in slag system Na2OSiO2- B2O3-CaO. During plant tests 18.5 kg of high gold grade primary concentrate were processed, 1350 g of dore gold and 75 kg of slag were produced. Dore gold contained 16.5% Au, 0.95% Ag, 78.0% Sn, 3.1% Fe. Slag contained 12.4 g/t Au, 6.7 g/t Ag, 9.8% Sn, and 5.6% Fe. Gold recovery to target alloy was equal to 99.58 %, 87.8% of Sn passed into slag. This new technology was accepted for application at the plant.

Jan 1, 2016

By V. H. Valenzuela

Materials in process or in stocks are quite relevant items in almost every plant, particularly in mining operations, where efficiency in rate of recovering material of interest becomes a key issue when production costs are evaluated. A manager requires information to do an effective use of the resources, especially when raw materials are involved. Losses associated to leaking, efficiency in the transformation process, performance of equipment, and operating conditions are a short list of items which must be properly identified and evaluated. Operations supervisors require information in order to keep key process variables under control. Because of these information needs, it is absolutely necessary to carry on a series of activities related with installation and maintenance of measuring equipment, sampling equipment, sample preparation, chemical analysis, statistical analysis, data handling and reports generation. These pieces of data must be managed on a wise manner in order to get the most of it, keeping always on mind data reliability. Normally, information related with metallurgical balance and even more, the metallurgical balance concept, is handled under an accounting criteria which does not allow dealing with the real world. This situation happens because the criteria utilized do not consider aspects such as bias and uncertainty associated with every measurement that affect the quality of the information and therefore conclusions drawn from it. The purpose of this paper is to give a few rules, necessary to follow, in order to develop an adequate Metallurgical Balance System for an operational point of view. The Gaussian approach for error propagation is used as a basis, allowing one to know the actual uncertainty of the balance and the way how it can be improved. A few real applications of this concept are listed, detailing experiences obtained from practice.

Jan 1, 2007

By S. A. Willis

For over 150 years gypsum from Nova Scotia has been shipped via water to the United States east coast. The history of the movement has been one of continual improvements in quarrying, loading, and shipping. At the start, man-size rock quarried by hand auger and black powder was loaded into horse-drawn carts, hauled to the waterfront, and dumped into 100-ton sailing schooners. Last year the Canadian Gypsum Company completed the latest and most modern of these successive installations for the movement of this Nova Scotia product. The new system loads crushed gypsum into 11,600-ton vessels at Hantsport in two hours' time at high tide. At the head of the bay of Fundy are located vast deposits of gypsum. The tidal rise and fall of 45 feet twice a day, with its attendant swift currents, has always presented major navigation and shipping problems. When the tide is low, the Hantsport ship-loading pier is high and dry, with no water within 400 feet. Three hours later a large river has flooded in (running up hill) and large steamers can dock at the wharf. Before high water, the ship has been loaded and -there is a depth of 30 feet or more of water around the wharf. At high water, the ship sails away on the ebbing tide as the river runs in the other direction. Tides are caused by the gravitational attraction of the moon and sun on the ocean. When both celestial bodies are pulling together the 'spring tide' results, which means a 50-foot variation from high to low. This occurs at new and full moon. A week later, when the sun and moon work in opposition, the difference is only 32 feet between high and low water. The bay of Fundy, having a funnel shape (150 miles wide at mouth from Yarmouth to Portland, while the upper estuary at Hantsport is only one mile wide), builds up a tidal influence from 10 feet at the mouth to an average of 45 feet at Hantsport.

Jan 1, 1948

By J. Bakos

Solar Hydrogen Energy Corporation (SHEC Labs) recently constructed a pilot-plant to demonstrate a Dry Fuel Hydrogen Generation System that is powered primarily by sunlight focusing-mirrors. The pilot-plant consists of: A Solar Mirror Array and Advanced Solar Concentrator and Shutter System; and two thermo-catalytic reactors to convert Methane, Carbon Dioxide, and Water into Hydrogen. Results from the pilot study show that Solar Hydrogen generation is feasible and cost-competitive with traditional Hydrogen production. More than 95% of Hydrogen commercially produced today is by the Steam Methane Reformation (SMR) of natural gas, a process that liberates Carbon Dioxide to the atmosphere. The SMR process provides a net energy loss of 30 to 35% when converting from Methane to Hydrogen. Solar Hydrogen production provides a 14% net energy gain when converting Methane into Hydrogen since the energy used to drive the process is from the sun. The environmental benefits of generating Hydrogen using renewable energy include significant greenhouse gas and criteria air contaminant reductions.

Jan 1, 2005

By S. Nikolic

"Calcium ferrite slags are currently used in a number of copper-converting processes. Despite the industrial importance of this system the phase equilibria have not been fully investigated. Characterization of this slag system is necessary to improve the control of process parameters, including fluxing and operating temperatures. Recently, a modified experimental method has been developed; this involves rapid quenching of slag samples equilibrated at high temperatures with the resulting phase assemblages analysed using electron probe microanalysis (EPMA). In the present study, experiments were completed under controlled temperatures and oxygen partial pressures using CO/C02 or H2/C02 gas mixtures. The investigated slags were supported during equilibration by a substrate of the primary phase. This technique removes the limitations arising from the use of crucibles and facilitates rapid quenching of the melt. Experiments were carried out at 1200°C and 1250°C (1473 Kand 1523 K) and in the composition range 0-40 wt.% Cu20, 0-25 wt. % CaO and 45-80 wt. % Fe203. Liquidus and solidus data are reported for the primary phase field of spinel between the oxygen partial pressures of 10-4.5 to 1 o- 6-5 atm. The analyzed compositions of liquids and solids are used to construct the phase diagram of ""Cu20"" -CaO-""F ez03"" system in equilibrium with metallic copper at fixed oxygen partial pressures."

Jan 1, 2007

By Matthew Violot

Vale Canada?s Birchtree Mine, located in Thompson Manitoba, has been experiencing problems with hanging wall / footwall dilution, as well as sloughing off of adjacent stopes and temporary stope block backs. Birchtree Mine is interested in determining how time affects the stability of their open stope blocks. Many factors simultaneously influence open stope stability (rock mass quality, joint condition, stress condition). This makes it challenging to determine the influence of a single parameter such as exposure time or stand-up time. This study focuses on determining the effect of exposure time on open stope dilution and combines stress analysis and empirical based approaches.

Jun 1, 2012

By P. J. Oakley, W. M. Thomas, S. W. Kallee, D. G. Staines

A Friction stir welding (FSW) is now extensively used in aluminium industries for joining and material processing applications. The (FSW) technology has gained increasing interest and importance since its invention at TWI almost 15 years ago. The basic principle, recent applications and the continuing development of the FSW technology are described. The paper will introduce some of the variants of FSW, such as Dual-rotation, Twin-stir(TM), and the Stir-lock(TM) technique.

Jan 1, 2006

By Michael S. Moats, Alex Luyima, Tomas Oliveira

Some commercial copper electrowinning facilities use Cyquest N-900 (a polyacrylamide) or HydroStar (a modified polysaccharide) to improve the density and smoothness of copper electrodeposits. However, the effects of these additives have not been studied extensively in the open literature. Thus, the electrodeposition of copper at 40 oC from a non-stirred synthetic electrowinning electrolyte (40 g/L Cu2+, 160 g/L H2SO4, and 20 mg/L Cl-) in the presence of various concentrations of either additive was evaluated using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). CV results show that neither additive has much effect on the nucleation overpotential of copper electrodeposition on stainless steel. However, Cyquest N-900 polarized the copper deposition reaction upon the return sweep. The EIS data indicates that Cyquest N-900 increases the reaction’s charge transfer resistance and creates a second low frequency loop. HydroStar had minimal effect on the electrochemical data generated by CV or EIS. Thus, the mechanism by which HydroStar affects the copper deposition reaction still needs to be determined.

Jan 1, 2014

By L. Frost

Physical Conditions Great Britain The physical conditions in the mines investigated in Great Britain are similar to those found in the mines of the Dominion Steel and Coal Corporation, with the important difference that many of the coal seams visited were interspersed by a large number of heavy faults, making the development of a continuous face operation difficult, and in many cases the life of a unit development was exceptionally short, adding to unit cost; but in spite of these difficulties, a great deal has been accomplished in the application of mechanical loading units in a number of the mines in the areas visited. The coal-bearing measures, as in Nova Scotia, consist of shales and sandstones, and in some sections mussel bands overlie the coal seams making roof conditions difficult'. In several mines, the main roof consisted of weak shale bind, being held by a coal roof of varying thickness. This shale bind had a tendency to flow when the coal roof was broken. The floor, in some cases where cutter loaders were operated successfully, consisted of weak, flaky shales with very little resistance and a tendency to disintegrate into powder when broken. The depth of cover under which these mines were operating varied from 250 feet to 2,340 feet, with an average of 1,700 feet. The coal seams varied in height from 3 feet to 8 feet 6 inches, and the gradients from level to 33 per cent. The seams vary in hardness, but all-with the exception of one seam, the 'Morrison Busty'- presented a cutting problem similar to that found in Nova Scotia. The structure and cleavage of the coal was well defined and uniform. Some of the seams visited were gassy, ?but the temperature of the workings generally was not in excess of 70°F.

Jan 1, 1948

By Kurt Tischler

This paper presents the field experience of Siemens with regard to Gearless Drives in the mining industry ? We consider the elapsed production hours of Siemens Gearless Drives to be extensive enough to provide a reliable estimation of availability calculated on the basis of data representing repair time, downtime, and operating time. The users of Siemens Gearless Drives confirm an availability of more than 98% after exclusion of some major issues. The paper addresses all of these major issues of Siemens Gearless Drives, describes successfully applied corrective measures, explains the influences on the design of the drives, and lists the downtimes associated with each of these issues.

Jan 1, 2012

By Q. F. Wang, M. H. Lai, T. Q. Liu, G. G. Dong

Compared with the traditional pre-treatment process, biological oxidation process has many advantages including higher gold recovery, less cost, easier operation. The bio-oxidation reactor is the most important equipment for biological oxidation process. In this paper, the characteristics of biological oxidation are investigated, and the design principles are proposed based on laboratory tests. Both increasing the tank height and taking new inflation system can enhance higher dissolved oxygen. The new type of large-scale industrial bio-oxidation reactor is designed, which is 9.5 m in diameter and 10 m in height. The bio-oxidation reactor metallurgical performance has been tested by industrial-scale experiment. The slurry of flotation concentrate is divided into two parts to feed two bio-oxidation reactors. The feeding rates of two reactors are adjusted on the basis of getting the same content of S, Fe, As in overflow. The result shows that the feeding rate of the new type of 700 m3 bio-oxidation reactor is 3.72 m3 per hour, and the feed rate of the conventional 700 m3 bio-oxidation reactor was 3.23 m3 per hour. The processing capacity of the former is 15.2% higher than that of the later, which demonstrates the new type of bio-oxidation reactor has higher oxidation rate.

Jan 1, 2015

By Brian Hart, Roger St. C. Smart, James Francis, Mark Biesinger

"There are a number of challenges involved with the surface analyses of different mineral phases from process streams in a flotation facility. The first of course is to collect samples that are representative of the process and to ensure that they remain in a pristine condition prior to introduction into the instrument. In mineral processing, sample collection from the different streams is done on site and preservation involves simply removing oxygen from the sample by bubbling nitrogen or argon gas through the sample and snap freezing with dry ice.The second challenge in studying the surface chemistry of specific minerals is to find reliable methods of mineral phase recognition. In surface analysis of mineral particles confident mineral selection can be difficult with many multi-metal minerals (e.g. chalcopyrite, pyrite, sphalerite) and with precipitated, adsorbed, reacted and contaminant species in the outermost molecular layers.In this paper we show that principal components analysis (PCA) of ToF-SIMS data provides improvement in phase recognition, particle selection and associated variations in surface species. We will demonstrate, with specific examples, that this technique can be utilized to differentiate surface chemical factors promoting (hydrophobic species) or inhibiting (hydrophilic species) flotation.Species recognition based on the PCA method in a study of Cu transfer between chalcopyrite, pyrite and sphalerite mineral mixture clearly identified a statistical difference in copper intensities between the sphalerite and pyrite phases. A similar ToF-SIMS/PCA based study applied to concentrate and tails samples collected from the Inco Matte Concentrator demonstrated extensive CuOH and NiOH transfer between the chalcocite and heazlewoodite minerals. The statistical analysis has been able to confirm some mechanisms and deny others proposed to control recovery and selectivity giving more focus on the control factors.The ToF-SIMS PCA statistical analysis has elucidated differences in surface chemistries which illustrate the discriminating depressant action of adherent aluminosilicate (gangue) fine particles and adsorbed ions on the surface of sphalerite grains. In the flotation test concentrates, HIC conditioning resulted in the removal of these gangue fines thereby improving surface collector attachment efficiency, promoting a greater recovery of sphalerite."

Jan 1, 2007

By John F. Kearney

Labrador Iron Mines (?LIM?) Schefferville Projects consist of 20 major DSO deposits lying along a 120 km strike length in both the provinces of Newfoundland and Labrador and in Quebec. The town of Schefferville, Quebec lies close to the middle of this 120 km strike. LIM?s various properties comprise twenty different iron ore deposits which were part of the original Iron Ore Company of Canada (?IOC?) direct shipping Schefferville operations conducted from 1954 to 1982 and formed part of the 250 million tons of historical reserves and resources previously identified by IOC. LIM intends to develop all these resources in five separate stages. The first four stages will see the various deposits treated in three beneficiation plants, to be built adjacent to several of the deposits that comprise the Central, South Central and North Central Zones. The final stage is not yet planned but will likely involve a fourth plant. A Feasibility Study has not been completed on any of these Projects. LIM plans the development and mining of the various deposits in separate Stages. It should be noted that only the James and Redmond deposits have been permitted. All other deposits require environmental assessment and permitting. Only the James and Redmond deposits have been subject to detailed mine design. The Houston deposit has had preliminary mine design carried out. All other deposits will require detailed mine design when further geological data is collected and compiled. Detailed metallurgical testwork has been carried out on blue ore from James, Houston, Redmond and Knob deposits and to a more limited extent on yellow and red ores from these deposits. Only limited review work has been carried out on the high-silica blue ores. All of this work will be needed to be complete to confirm the final process routes. Additionally some metallurgical work will be required to be conducted on each of the other deposits to characterize their metallurgical response and to confirm expected recovery levels. Detailed mine design and metallurgical testwork has been carried out on those deposits that will form the basis of production for the initial years but further exploration, testwork and design is required for all the remaining resources. The first plant at Silver Yards and mine construction at James are now complete and initial production is expected in the spring of 2011. Metallurgical testing of the first stage deposits has established that the ore can be successfully upgraded to marketable standards. Based on the current testwork, a program of plant enhancement on the Silver Yards plant is now planned with the objective to increase both the plant throughput and recovery. Production of direct shipping lump ore and sinter fines is forecast at around 1.5 million tonnes in 2011 and, based on current and historical resources, growing to approximately 5 million tonnes in 2015 and thereafter. Production from the first four stages is expected to continue at about this rate through to about 2028.

May 1, 2011

By I. E. Puddington, F. W. Meadus

The beneficiation of barite in mill tailings using an agglomeration technique has been demonstrated. Barite was selectively absorbed from a conditioned aqueous slurry into a collector oil by mechanically mixing slurry and oil. The resulting oil-bonded barite-containing agglomerate was washed, to remove gangue material, and further mechanically contacted with dilute H2SO4 This treatment resulted in the transfer of barite into the aqueous phase. Grades as high as '97% BaSO4, with recoveries of 80%, have been obtained using this technique.

Jan 1, 1973