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By R. Marleau, R. Assad, J. Dugas

"A study of the geological features of known occurrences of mineralization in Gaspe is the basis for a classification. Nickel, chromite, asbestos and some copper are pre-or syn-Taconic, whereas the most important deposits are tied to granitic post-Taconic stocks. Most occurrences are clearly related to igneous rocks: nickel, chromium and asbestos to Ordovician serpentinite; copper to volcanic rocks of different ages; and copper, zinc and lead to acidic intrusions with apparent zoning. Some lead-zinc deposits lying between the Grande Greve and York Lake formations are stratigraphically controlled. Some occurrences are tied to faults; e.g., the nickel-copper mineralization along the North Grand Pabos fault. Northerly-trending transverse structures appear to coincide with the Gaspe Copper, Mount McGerrigle (Tabletop) granite and Lemieux dome areas of mineralization. JEAN DUGAS, after graduating"

Jan 1, 1969

By M. Zamalloa, P. J. Mackey, P. Coursol, Y. Prévost

"Over the last decade or so, the availability of commercial thermodynamic modelling packages, such as FactSageTM, have been utilized to help the plant optimize slag chemistry and to minimize slag handling issues that can arise, such as those due to a process upset, for example, by undue feed variability. This paper illustrates an extension of the application of this software in examining a large range of NCV operating parameters, such as the %Fe/SiO2 ratio in the slag and the level of minor gangue components in the slag including CaO, Al2O3, ZnO, MgO, and PbO. The conditions influencing the slag liquidus range of NCV slag are discussed with respect to the overall process chemistry.Given that a sufficiently low %Fe/SiO2 ratio is used in NCV slag, most components such as CaO-ZnOPbO- Al2O3-MgO, in small concentration, all contribute to lowering the NCV slag liquidus. Considering the present level of these minor components, the NCV can operate consistently at 1200°C if the %Fe/SiO2 is between 0.6 and 0.8 in the slag. Using the type of phase diagrams presented in this paper, it is possible to develop different Noranda reactor/Noranda converter operating strategies adapted to the feedstocks available at Xstrata mines/plants or from other sources. The NCV is unique in that a fayalite-based slag is employed for high-efficiency continuous converting with excellent operating results."

Jan 1, 2007

By M. A. Rabah

This study aims to recover europium, yttrium metals, some valuable salts or oxides from the white powder (apatite) coating the inner surface of spent florescent lamps (SFLs). Pressure leaching using sulphuric/nitric acid successfully dissolved the metals of interest. Europium or yttrium metals were obtained by hydrogen reduction of their oxides. Addition of potassium thiocyanate converted the dissolved sulphates to thiocyanates. Selective separation of Eu and Y was then carried out by solvent extraction from the thiocyanate solution. The used solvent was trimethyl-benzylammonium chloride. N-trihutylphosphate in 1 M nitric acid was used to strip the metal loaded in the organic phase. Results showed that the quality of the cleaned glass tubes of the SFL met the standard requirement for the lamp manufacture. The white powder (WP) is composed of calcium sulphate 35.2%, phosphate 61.5% and oxides of europium and yttrium 1.65%wt. respectively. Autoclave digestion of the WP for 4 h at 120°C and 500 kPa in sulphuric acid/nitric acid mixture dissolved 96.4% of yttrium and 92.8% of europium. The conversion rate of sulphate to thiocyanate was favoured at low temperature. Stripping of Eu and Y from the loaded organic phase behaved in an opposite way. A metal separation factor of 9.4 was obtained. ate recovered europium and yttrium salts were selectively separated using ethyl alcohol or dilute nitric acid. Yttrium was very soluble while europium was not. Europium and yttrium metals were obtained by hydrogen gas reduction at 850°C and 1575°C respectively.

Jan 1, 2004

Cameco Corporation is in the process of revitalizing the Key Lake mill. As part of this process, the company is considering installing the Rabbit Lake style strong acid stripping in solvent extraction. This would lead to using hydrogen peroxide for uranium precipitation. The process currently employs ammonia stripping and ammonia precipitation. As part of the process evaluation, an indirect fired drier pilot plant test was conducted. This paper will discuss the results of that test work, including the relationships between the following: ? Drying temperature and product grade ? Drying temperature and product colour ? Drying temperature and product reactivity with water ? Drying temperature and energy input requirements ? Drying temperature and shipping costs

Aug 1, 2010

By Hökmark. H., M. Lönnqvist

"The Swedish Nuclear Fuel and Waste Management Company are planning to construct a permanent storage facility for high-level nuclear waste at about 500 m depth in fractured crystalline rock. One potential concern for the long-term performance of the repository relates to large fracture shear displacements, since these may damage intersected waste containers. Although details in fracture surface geometries are known to influence slip magnitudes and distributions, fractures are commonly approximated as planar features with lab-scale properties due to lack of relevant field-scale data and to limitations in available modelling tools. The purpose of the work described in this paper is to explore the possibilities to use the distinct element code 3DEC to generate and analyze models with isolated, non-planar fractures and, based on the results of such models, get perspectives on the influence of basic disturbances such as ridges, steps and waves. Given the model set-up, fracture segments with orientations deviating from the critical one will contribute to stabilize the fracture. As a result, all analyzed non-planar fractures slip less than the critically oriented planar fracture. We demonstrate that the angle of deviation is the most influential parameter determining the slip magnitude for comparable surface geometries. Similarly inclined steps and ridges have almost equal slip reductions despite differences in surface area restricting the movement. Although it may be possible to translate the influence of such irregularities to an effective coefficient of friction that could be used as input to models with idealized planar fractures, additional analyses with randomly shaped and distributed asperities, different fracture sizes and with alternative stress loads, need to be carried out to devise a defensible strategy for this type of parameter variation. INTRODUCTIONThe Swedish Nuclear Fuel and Waste Management Company’s (SKB) concept for deep geological storage of high-level nuclear waste is the KBS-3 method according to which the waste will be encapsulated in copper canisters and deposited, surrounded by compacted bentonite clay, in vertical deposition holes at about 500 m depth in fractured crystalline rock (SKB 2011). A site has been selected in the Forsmark area, which is located some 120 km north of the Swedish capital Stockholm. One potential concern for the long-term performance of the repository that has been identified by SKB (SKB 2011) is related to large shear displacements along repository host rock fractures induced by a nearby earthquake, since these may cause mechanical damage to intersected waste containers. Due to lack of relevant data at the appropriate field scale and to limitations in available modelling tools, fractures are commonly approximated as planar features with lab-scale properties. The standard numerical tool, 3DEC (Itasca 2013), used in SKB’s rock mechanics analyses, for example, generates planar fractures by default. Results from dynamic 3DEC earthquake-models (Fälth et al. 2010) currently provide input to layout decisions, i.e., the diameter of the smallest planar fractures that must be avoided when deciding on waste container positions at different distances from potential earthquake faults. It is, however, well known that fracture surfaces are rough or undulating on a wide range of scales (e.g., Candela et al. 2012) and that such deviations from planarity influence the mechanical behaviour of the fractures (e.g., Dieterich and Smith 2009, Marshall and Morris 2012, Ritz and Pollard 2012). It will probably never be a realistic option to attempt to represent the geometrical complexity of a population of fractures of different size, shape and surface structure in any large-scale rock mechanical analysis relevant for the performance assessments of the nuclear waste repository. It may however be possible to find approximate ways to represent different styles and degrees of non-planarity by assigning mod"

Jan 1, 2015

By K. P. Plucknett, Z. Memarrashidi

WC-Co ‘hard metals’ are widely used in a variety of industrial applications due to their resistance to abrasive wear, in addition to their high hardness and toughness. However, in contrast to their mechanical properties, the corrosion response of these materials is relatively poor. In the current work the corrosion mechanisms of two WC-Co cermets are analysed, with 10 and 30 vol. % of the Co metal binder, in a 3.5 wt.% NaCl aqueous solution. The assessment of corrosion involved a variety of electrochemical measurements, including open circuit potential, potentiodynamic polarisation and cyclic polarisation, together with systematic analysis of the post-corrosion solution chemistries using inductively coupled plasma optical emission spectroscopy. The corrosion potential and current density were determined, following Tafel extrapolation, allowing the calculation of the corrosion rates. It is demonstrated that continuous dissolution of the cobalt phase occurs during corrosion, which is a result of poor cermet passivation behaviour, and this response increases with the amount of binder in the cermet.

Jan 1, 2015

By Sabine Noelte, Mikko Petteri Rantamäki, Christopher Robben, Anssi Takala, Karl-Erik Rånman

"Sensor-based ore sorting is on its way to establish as a standard option for physical separation. The increasing number of installations in coal, iron ore, industrial minerals and hard-rock metal mining segments underlines the technological and financial potential that is beginning to be untapped. The Ma’aden Phosphate installation with 1.650 t/h sensor-based ore sorter feed sets a new benchmark for the possible capacity of stationary installations. Besides stationary installations, including multiple sorters parallel in different size ranges and multiple stages, containerised semi-mobile plants are applied. These offer two advantages, first being the reduction of transport costs when applied close to the mining face. The second is that semi-mobile systems enable processing of tens of thousands of tonnes of ore in a piloting phase with an approximate duration of 0.5 to six months, verifying the results laboratory mini-bulk tests on 5–10 tonnes of sample. This is especially important for low-grade metal ores because of the inherent Fundamental Sampling Error, as well as the Grouping and Segregation Error. The paper elaborates the results achieved within the I2MINE project, treating polymetallic ore at the Boliden Concentrator in Sweden.INTRODUCTIONSensor-based ore sorting (SBS) is becoming a standard option for physical separation, applied in all segments of mineral production. The Umm Wu’al project sets the bar for stationary SBS installations with 1,650 t/h feed (TOMRA, 2015). TOMRA Sorting Solutions has finalised an agreement in cooperation with Outotec to supply Outotec-branded sorting solutions for the mining and metallurgical industry (TOMRA, 2014). Especially for low-grade hard rock metal ores, an interdisciplinary approach is necessary applying experts for all aspects of mineral production. Due to the impact on the whole process stream, it is important on the end user side to have high level managerial support and involve all disciplines to ensure that all stake holders are involved in the analysis."

Jan 1, 2016

By D. Runnels, Daniel Roy, Ricardo Esteban, J. Torrealba-Vargas

"An intuitive way to reduce power consumption in grinding operations is to feed the grinding circuit with finer feed by enhancing blasting and fragmentation control. The optimization of blasting with the objective of minimizing power consumption in grinding is not new.The study was based on a Canadian mine that processes a very hard ore. BBA conducted blasting/fragmentation and grinding circuit surveys in 2014. The results of the exercise were used to develop a base case model to simulate the effect of blasting in the operation on the grinding circuit. Tools for fragmentation simulations, particle size measurement and crushing/grinding simulations were used with the objective of reducing the OPEX costs including power consumption.The paper describes the steps involved in the model optimization as well as an economical evaluation of the OPEX savings.INTRODUCTIONIn 2014 BBA was retained by one of its clients to conduct a crushing and grinding survey. The objective of the survey was to update the grinding circuit model with production data and also to develop a tool to investigate opportunities for process improvement.A second phase of the study involved the development of drilling and blasting and crushing models. The models were used to diagnose the operations and to investigate opportunities for process improvement.The objective of the present study is to describe the approach and to identify potential improvements to overall mine site operating costs by better integrating mining and milling operating costs with blasting and grinding models."

Jan 1, 2016

By L. Jiang

This report investigated the dynamic recrystallization (DRX) phenomenon in magnesium alloy AZ31 billets to understand the deformation mechanisms and microstructure evolution during extrusion and other metal forming processes, Compression tests of coarse-grained as-cast magnesium alloy billets containing lamellar Mg17Al12 eutectic phase and (Al, Mn) particles suggest that temperatures higher than 300°C, strains greater than 0,25 and strain rates above 0,l/s lead to the formation of fine DRX grains in the deformed samples. Microstructural observations also indicate particle-stimulated DRX nucleation (PSN) during hot deformation of the AZ31 alloy, facilitated by the presence of Mg17Al12 and (Al, Mn) particles, While the Mg17Al12 is dissolved into the matrix at about 350°C, (Al, Mn) particles may remain effective for PSN at temperatures up to at least 400°C, This study suggests that alloy design with a proper distribution of second-phase particles can provide the desired microstructure for improved properties and formability in wrought magnesium alloys.

Jan 1, 2004

By C. Diaz, S. W. Marcuson, K. I. Burgess

Deep roasting in fluid bed roasters is the first unit operation in Inco&apos;s "roast-reduction smelting" process for the treatment of nickel sulphide concentrates. The roaster product, a low sulphur calcine, is reduction smelted with coke in an electric furnace to yield a sulphur-deficient matte which is then converted to low (<1%) iron matte in Peirce-Smith converters. Due to the deep roasting, a minimal amount of sulphur dioxide is evolved in the smelting and converting stages. Sulphur is eliminated from the concentrate almost exclusively in the roasters in a single, continuous, strong, gas stream suitable for treatment in an acid plant. This paper discusses the commercial scale testing of deep fluid bed roasting of nickel concentrate at Inco&apos;s Thompson Smelter as part of two commercial scale campaigns on roast reduction smelting conducted in 1981-1982. Slurry feeding, practised during the second campaign, permitted excellent control of the air/concentrate ratio in the roaster and, in turn, good control of sulphur elimination (about 80% of input). Smooth autogenous operation with high oxygen efficiencies (about 95%) was promoted by operating at bed temperatures of830°C to 850°C with calcine recycle. High throughputs and the desired metallurgy were achieved. The extensive testwork conducted during the two experimental RRS campaigns demonstrated thot deep fluid bed roasting of nickel concentrate at high oxygen efficiency is a technically viable operation.

Jan 1, 1994

By Geir M. Haarberg

Electrochemical techniques, mainly linear sweep voltammetry and potential step chronoamperometry, were used to study the behaviour of dissolved phosphorus species in cryolite-alumina melts, The presence of AIPO4 or Na3PO4 gave rise to voltammetric current waves due to electrode reactions involving phosphorus species at potentials where dissolved alumina is stable in cryolite melts, Diffusion kinetics for dissolved P(V) species were studied, Data from industrial cells were used to determine mass balances for phosphorus, For cells being fed with secondary alumina, more phosphorus tends to end up in the produced metal, Laboratory experiments to study the effect of phosphorus in the bath on the current efficiency for aluminium were also carried out.

Jan 1, 2004

By J. Drenda

The model for methane removal from the workings directly behind an advancing longwall as presented in this paper may be used for U-ventilated cross or length-wise systems of longwall advance, starting from the boundaries of the extraction field. In mines with high methane concentrations, Uventilated longwall extraction from the boundary of the extraction field produces a methane risk. The risk is manifested by a higher methane concentration at the end of the longwall, upper gate and incline. The methane in increasing concentrations, which is emitted mainly from the workings with caved areas, appears towards the end of the longwall and in the upper gate. The graphical model of the longwall provided includes both the workspace of the longwall and the caved area. Based upon a model of the rock distribution in the cave, a ventilation model comprising two standard air splits and large number of crosswise air splits has been constructed. Simulations indicate that if the shearer is not present in the longwall, the air distribution in the caved area is symmetrical. The presence of the shearer, both at the bottom and the top of the longwall, causes an asymmetrical air distribution in the cave, that is the asymmetrical flows in the goaf and longwall workspace and in the inflows and outflow between those regions. This phenomenon causes an increase in methane concentration at the end of the wall and at the upper gate. The methane removal method proposed for workings with a caved area directly behind the advancing U-ventilated longwall, starting from the boundary of the field, consists of the removal of methane-air mixtures from the caved area with the boom pipes. These booms may be of several meters long and may be extended if necessary. The insertion of the boom pipes into the cave towards the end of the longwall and connecting them with the general methane removal system creates negative pressure causing a change in the depression field, which is the aerodynamic potential field in the goaf area around the ends of the boom pipes. This will promote the extraction of the methane-air mixture from voids and the goaf cracks, and the area from which methane is being extracted may extend to the side of the cave. This is a positive phenomenon, which could result in the methane flow from the goaf into the airflow in the longwall workspace decreasing or even stopping. A reduction in the methane flow into the longwall workspace with extractions booms will be advantageous for the production continuity. Based on the floor load model for the rocks in the cave and the methane-removal boom load model, the value of the force required to move the boom behind the advancing wall has been calculated. Strength calculations for the pipe were performed using a finite elements method. The analysis results, as well as the comparison of the pipe material effort to the strength parameters of steel, which can serve as piping material (for the assumed load conditions), lead to a belief that the proposed boom construction satisfies the strength requirements.

Aug 1, 2013

By Robert J-M Ethier

"Sequential blasting has been introduced at Mines Gaspe to reduce the harmful effects associated with the instantaneously primed blasting method. Three stages of modifications had been tried to improve this method: trials of a rectangular pattern instead of the square one, trials of lengthened hole collars at the perimeter of the blast and trials of increased inter-row delay intervals from 35 to 50 ms. Results showed that improvements to the instantaneously primed blasting method were limited by the probability of increasing the number of bootlegs.Doing these modifications allowed the definition of a general approach to improvements before the sequential blasting method was introduced. This general approach included: planning of the mining sequence, following up on the drilling, loading and tying-in of each blast, compiling and evaluating blast results, comparing results from one bench to the other and moving along with one change at a time. This approach has permitted the successful introduction of the sequential blasting method in two steps: trials of blast by rows of delayed holes and trials of hole-by-hole blasts. The optimum result has been analyzed by high-speed camera and by computer blast simulations, The actual optimum sequential blast is obtained with a CORDLINE priming system using period 15, permitted in a large drilling pattern, with an intersequences delay interval of 230 ms and an inner-sequences delay interval of 50 ms.While these modifications were being introduced, a careful study of the drilling and blasting costs was made, which showed a sharp reduction of drilling cost per tonne. Even though there was an increased use of packaged slurry the blasting cost per tonne also dropped. The reduction in cost per tonne was explained by the fact that the average energy factor was maintained while the blasting pattern was expanded.The sequential blasting method, successfully introduced at Mines Gaspe, permits blasts of better quality, reduces the drilling requirements by more than 30% and helps to achieve improved productivity while minimizing costs."

Jan 1, 1984

By R. B. Casault, J. D. Boyd, D. R. Bell

"Full-scale sections of three different types of Grade 483 line pipe have been evaluated extensively. The variations in chemical composition, optical microstructure, tensile properties, hardness and Charpy impact toughness with specimen orientation and location were determined. Significant variations in several properties, notably Charpy shelf energy, impact transition temperature, inclusion content and ferrite grain size, were observed for different locations in the pipes. The results indicate that current specifications call for test samples for the most conservative locations, except for impact tests. Minimum Charpy impact values generally occur at the II2-width location, which may be a more appropriate specified test location than the present I/4-width location. The anisotropy of impact toughness, and the importance of low sulphur content and inclusion shape control for adequate toughness in the transverse/rolling-direction orientation were demonstrated. The orientation of impact specimens is critical for spiral-weld pipe, and the current specification test is non-conservative in that it can give results which are two to three times higher than the minimum value for the steel.IntroductionThis report presents the results of an extensive metallurgical evaluation of three different Grade 483 line-pipe steels. The sample material came from full-scale sections of line pipe, which represented current commercial practice at the time of manufacture (1975-1977). Since then, significant improvements have been made in the manufacturers&apos; procedures for producing skelp and pipe, and the line-pipe specifications have been revised. Hence, the information in this report is dated in terms of current design, but it is unique and significant in several respects:"

Jan 1, 1982

By Godfrey MacDonald

"The East West Caribou deposit with an underground mine, concentrator and ancillaries is located 30 km west of Bathurst, New Brunswick. The Restigouche deposit, an open pit mine is 30 km west of East West Caribou. The ore will be trucked from the Restigouche site to the East West Caribou minesite.History:The East West Caribou ore body was discovered in 1955 and the subsequent metallurgical programme focused on producing a bulk sulphide concentrate. However, in 1966 a Mr. P.G. Kihlstadt of Anaconda did float a Copper-Lead concentrate and a Zinc concentrate. He also reported that as the grind became finer the recoveries improved. In 1968 the Mines Branch in Ottawa produced a Lead concentrate of 30 percent at a 60.5 percent recovery and a 52 percent Zinc concentrate at an 83.4 percent recovery.Laboratory testwork proceed the 1988 start up of our current concentrator and underground mine facilities. The concentrator was designed to produce a Lead ""rich"" concentrate and a Zinc ""rich"" concentrate which were combined to make a marketable Bulk concentrate. In 1990 the operation was suspended because of declining base metal prices, increasing smelter treatment charges, increasing operating costs and operating difficulties.The 1997 operating plan is to produce a Lead concentrate and a Zinc concentrate.The Restigouche ore body was discovered in 1989. The subsequent testwork done at Lakefield Research recommended the production of a Copper, a Lead and a Zinc concentrate. The ore reserve could not support a stand alone concentrator so the project was put on hold.Laboratory testwork was carried out at Lakefield Research to confirm compatibility of the East West Caribou ore and the Restigouche ore in their processing."

Jan 1, 1997

By Elaine R. Goetz

The eastern and southeastern regions of Ohio are part of Appalachian coal country, with a documented 1,300 miles of streams impacted by acid mine drainage. Since 1995, partnerships of local watershed groups, government agencies, private industries and universities have focused on the remediation of the affected waterways. The partnerships have spent $2.4 million annually in constructing and operating treatment systems such as wetlands, anoxic limestone drains, successive alkalinity production systems, steel slag leach beds, and lime dosers. These systems have been partially successful, and water quality has improved in the region, but no treatment has yet met the ultimate objectives of low cost, continual remediation. Our research group has investigated an alternative system for acid mine drainage treatment: electrolysis combined with pH adjustment to selectively precipitate recoverable, saleable metal products to offset the cost of treatment. We utilized a $0.2 million pilot facility constructed by the Wayne National Forest, in Nelsonville, Ohio, to process approximately 40 L/min of mine drainage from surrounding seeps. The pilot facility has multipurpose tanks that can be adapted to process acid mine drainage with different characteristics, such as high or low aluminum content or high or low carbonate concentrations. Sodium hydroxide was used for pH adjustment. Results indicate that saleable product can be generated with this treatment technology. In an initial, not optimized trial, one seep yielded 4.7 kg of dried 69 % iron oxide product from 10 hours of pilot facility operation, treating 23,000 L with electricity costs of $4.68. Dissolved iron concentrations in the water were reduced from 242 ± 18 mg/L to 2.8 ± 2.0 mg/L (99.0 % removal) while the initial acidity of 443 mg/L as CaCO3 was neutralized to an alkalinity of 160 mg/L as CaCO3. Iron oxide can be sold as pigment for an average of $1.47 per kg in the United States. Currently, approximately 80 % of all pigment used in the United States is imported, and there is incentive to purchase domestically recovered pigment. If the iron oxide from the pilot facility could be sold as pigment for $1.47 per kg, 43 % of the operating cost (raw materials, electricity and construction costs) of treatment could be offset by the sale of the product. Considering the cost offset, the electrolysis process shows potential as a sustainable low cost alternative for treating acid mine drainage.

Aug 1, 2013

By K. Huang

"Solvent extraction (SX) is one of the most effective techniques for the multi-metal separation. However, repetitive pre-treatment of feed-in solutions and/or multi-steps two phase equilibrating in conventional SX processes were always unavoidable due to the poor separation selectivity between those metals with similar physicochemical properties. In this paper, our recent efforts, aimed to develop a “Three Liquid Phase Extraction” (TLPE) strategy for one-step separation and selective enrichment of different metals respectively into three coexisted liquid phases, are reviewed. Various feasible “Three Liquid Phase Systems” (TLPS) are evaluated. The TLPE technique provides a potential possibility for multiphase extraction to separate multi-metals.INTRODUCTIONLiquid-liquid Solvent Extraction (SX) is one of the most effective techniques for metal separation and purification. Traditionally, extraction and separation of multiple valuable metals from the leaching solutions of complex ores, industrial wastes and byproducts have to face such difficulties that multiple target metals with similar physicochemical properties co-exist in the solutions, and therefore their mutual separation selectivities are very poor. In conventional organic-water two phase SX processes, repetitive pre-treatment of feed-in solutions including the adjustment of the solution acidity, removal of impurities and/or multi-step liquid-liquid two phase equilibration were always unavoidable (Wang and Chen, 2001). Only one of the target metals is obtained in each extraction step, therefore the whole separation processes for multi-metal separation are typically very long and costly.Liquid-liquid-liquid three phase extraction is a developing technique for separation of complex systems containing multiple target components (Tan, 2003; Shen, 2006; Yu, 2009). The technique is in fact a three-liquid-phase selectively partitioning of different target components through the control of phase-forming behaviors of extraction system to create a unique separation medium with three co-existed liquid phases. The separation selectivity of “Three-Liquid-Phase System” (TLPS) may derive from its three-layered liquid phases from up to down with different hydrophobic or hydrophilic environment, and therefore each phase has its own specific selectivity for dissolving of an individual component. In a well designed “Three-Liquid-Phase System” (TLPS), multiphase extraction and selective separation of different components respectively into three different liquid phases can be achieved by only one-step of extraction. Owing to its distinct advantages, “Three-Liquid-Phase Extraction” (TLPE) technique has found many potential applications in purification of various organic chemicals (Shen, 2007) and biological activities (Chen, 2002; Tan, 2006; Jiang, 2008), treatment of environmental wastewaters (Shen, 2006; Yu, 2009; Yu, 2010; He, 2012), extraction of valuable components in natural products (Liu, 2010) and separation of multi-metals in complex leaching solutions (Jin, 2009)."

Jan 1, 2012

By Quenton Johnson, W. A. Gough, David Carr

"This paper describes the application of the BrainWave Model Predictive Controller (MPC) and Advanced Control Expert (ACE) Advanced Supervisory Control System on the SAG Mill, Ball Mill, and Rougher Flotation cells for a new gold processing line at the Oceana Gold - Haile Gold mine in Kershaw, South Carolina. For this project, ANDRITZ supplied the control system design and programming, operator-training simulator and advanced control. The advanced control was tested against the IDEAS™ dynamic simulator, and commissioned during the startup of the processing plant to help achieve target production as quickly as possible. Operators were able to run the equipment in a consistent and optimized manner from an early stage of the plant operation, increasing efficiency and profitability. MPC is able to reduce process variability beyond the best performance that can be obtained with conventional Proportional Integral Derivative (PID) control methods. MPC is able to optimize the control of processes that exhibit an integrating type response in combination with transport delays or variable interaction, which are characteristic of many gold processes including SAG mill weight control and Flotation cell froth level control. The experience and benefits of applying MPC during the startup of a new gold processing plant are presented in this paper.INTRODUCTION Mineral processing operations present many challenges for automatic process control due to variations in unmeasured ore properties, material transport delays, and non-linear response characteristics. Advanced process control technologies such as expert systems and multi-variable model predictive controllers are often used to improve the control of these processes to increase productivity and recovery efficiency. Typically these systems are applied after the mine has been in operation for a period of time. For this project, a complete dynamic process simulator was developed using the IDEAS platform for the purpose of training operators before the plant was constructed. Operators were able to become familiar with the process and the control system in order to become proficient in the use of the controls before the plant was ready to start. They were able to practice abnormal condition management including startup and shutdown of the process using the simulator and develop complete Standard Operating Procedures (SOPs) for these situations. The simulator was also used to test the control system functionality and operator Human Machine Interface (HMI) configuration to reduce errors and improve the performance of the control system during plant start-up."

Jan 1, 2017

By J. V. Thirgood

"Reclamation legislation was introduced in British Columbia in 1969 amidst public concern and controversy. This paper reviews this legislation as it relates to coal mining, and how it is being implemented.Although the principles of land reclamation are reason-ably well understood, reclamation of industrial wasteland has never previously been attempted under such rugged conditions as occur in the Canadian Rockies and a new methodology is being developed.The resolution of the technical and organizational problems involved are discussed and the techniques and experiences described."

Jan 1, 1971

By A. Bamber

Canadian leadership in a global mining context will depend not only on entrepreneurship and best practice but also on technological innovation. This paper argues for more ambition and commitment to R&D for technological innovation in Canadian mining. It focuses on underground hardrock mining, where past R&D initiatives have simply not stood the test of time, and it is important to examine why. Concerns arise because industry’s commitment to R&D has not been sustained over time. Innovation through exploration, processing, and environmental technologies has been more significant. Meanwhile, R&D capacity and synergies in government institutions and universities have not been exploited. There is a need for more commitment, coordination, and collaboration by industry, governments, and universities. This paper examines some corporate models that have achieved sustainable innovation, along with some that have not. A strategy for innovation is discussed that relates to culture, commitment, coordination, and collaboration.

Jan 1, 2005