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By Thomas Genty, Pascal Marcotte, Matthew Gillman, John Baechler

Elevated concentrations of ammonia nitrogen is a common characteristic of mine impacted water and generally results from the dissolution of undetonated explosives (i.e., Ammonium Nitrate and Fuel Oil and emulsion explosives) by contact water. Several active water treatment technologies are commercially available to remove ammonia nitrogen, but reduction of active treatment demand by promoting natural attenuation is considered best industry practice. In this paper, the results of laboratory-scale and full-scale trials of a semi-passive approach (i.e., enhanced algae growth) to remove ammonia nitrogen at the Meliadine mine are presented. Phosphorus was found to be the limiting factor to algae growth at the mine site. The addition of various concentrations of phosphorus was first tested at a laboratory scale. The samples were exposed to in-situ conditions, and ammonia nitrogen removal rates ranging from 40% to 93% were achieved over a period of 24 days. This paper also presents the methodology and results of an in-pond treatment during which a 50% ammonia nitrogen removal rate was observed after 68 days. The studied mine site uses breakpoint chlorination as its primary treatment approach for ammonia nitrogen removal. The results presented in this paper show the potential of using enhanced algae growth as a pre-treatment method, subsequently reducing the quantity of chemicals required for operating the breakpoint chlorination plant. This potential requires further investigation and additional trials are currently under evaluation.

Jan 1, 2023

By G. Zárate, G. Tapia

Anglo American Chile has been doing copper concentrate leaching studies at the laboratory and small pilot plant scale since 1992. Among the processes evaluated are bacterial leaching and pressure leaching using Mantos Blancos, Salobo Project and Quellaveco Project concentrates. Late in the nineties, it was decided to focus the research on pressure leaching, either medium or total pressure oxidation. Preliminary scouting tests were run with Mantos Blancos concentrate samples during 2000, which were repeated during 2003 together with samples of Los Bronces and El Soldado concentrates, in order to define the most suitable concentrate for running a pilot plant campaign at AARL, which was carried out in two campaigns, a first one from November 2003 through January 2004 and a second one during April 2004. Mantos Blancos was the selected concentrate and the laboratory and pilot plant results are discussed in this paper together with some preliminary economic estimates.

Jan 1, 2004

By S. Mostaghel, Fariba Azgomi, Steven Goodman, M. Oliazadeh

"It is known that copper loss to the slag phase can be in the forms of chemical dissolution and mechanical entrainment. The contribution of each mechanism to the total Cu-loss depends on different parameters and may vary significantly. To reduce emissions to the atmosphere and to shorten the converting cycle, most industrial processes are aiming at production of high matte grades. Increased oxygen-to-sulfur potential, required by these processes, results in a highly oxidized slag, which in turn leads to an increased concentration of the chemically dissolved copper in the slag phase. Hence, slag cleaning processes are becoming increasingly important for economic viability of the smelting operations. Hydrometallurgical, pyrometallurgical, and mineral processing routes have been used for copper recovery from slag. The current article reviews a trade-off study evaluating two of the commonly used methods (namely flotation and electric slag cleaning furnace) by comparing the technical pros and cons, operability/maintenance requirements, and capital/operating costs of the operations.INTRODUCTIONLarge volumes of smelter and converter slags are produced by copper smelters around the world. It is estimated that for production of each ton of metal 2.2 tons of slag is produced (Gorai, Jana, & Premchand, 2003). Considering the current pressure on the mining and metals industry for “zero-waste, sustainable and environmentally friendly” extraction of metals, it is absolutely essential for metal producers to improve their efficiencies in order to remain competitive. To meet these objectives, almost all metal producers, from steelmaking plants, ferroalloys, base and precious metals producers, are trying to reduce their metal losses to the slag phase. In particular, copper producers are aiming to produce higher matte grades in their smelting furnaces to reduce the converting time and improve their overall throughput. Copper smelters need to minimize their copper/precious metal losses to the slag phase before final landfilling/use of slag. The current article, therefore, briefly reviews the copper loss to the slag phase, methods of metal recovery from the slag and then presents a trade-off study conducted for a green field flash smelter of the sulfide concentrates. A comparison was made between two of the major process routes for metal recovery from slag, namely slag cleaning furnace and flotation."

Jan 1, 2016

By Henk Dijkman, Wageningen University, Paula Gonzalez Contreras, Irene Sánchez-Andrea, Jan Weijma, Silvia Vega

"More than 20 years ago, Paques B.V. introduced innovative biotechnologies to recover metals and to remove sulfate from aqueous streams. These technologies find their origin in the exploration of microorganisms involved in the global sulfur cycle. Currently, several sulfur cycle biotechnologies are applied successfully at full-scale. The sulfur cycle is closely linked with the iron cycle, and also the latter offers opportunities for application of innovative biotechnology for the mining industry. Microorganisms of the natural iron cycle carry out reactions that are not feasible by chemical methods such as ferrous iron oxidation with oxygen at pH below 4. Iron oxidation with oxygen can be conducted using microorganisms living at pH between 0.5 and 7 and at temperatures between 0 and 95ºC. Remarkably these microorganisms can also carry out arsenite oxidation at similar acidic conditions and high temperatures. Making use of the extreme features of these microorganisms, Paques and Wageningen University have developed a biological process to precipitate arsenic as scorodite. This biological formation of scorodite is a novel combination of biological oxidation and biocrystallization. Depending on the level of saturation, biological oxidation rates and operational conditions, we could control the formation of the iron precipitates such as jarosite and scorodite. Currently new microorganisms have been harvested from hot springs and rock acid mine drainage to foster the growth of specialized microbial communities with potential high iron and arsenic oxidation capacities and higher resistance to other metals. In our paper we address the ongoing research and development of the bioscorodite process.THE USE OF IRON TO REMOVE ARSENIC In 2015 several environmental disasters related to the release of mine wastewater and tailings occurred. On August 5th, a waste water spill occurred from the Gold King Mine near Silverton, Colorado. A dam holding the tailing pond was damaged and spilled three million US gallons (11 ML) of mine wastewater and tailings, including elements such as cadmium, lead and arsenic, into Cement Creek, a tributary of the Animas River in Colorado. “At their peak, arsenic levels were 300 times the normal level and lead was 3,500 times the normal level” (The Guardian, 2015). In early November, another collapse of a mining dam in the Brazilian state of Minas Gerais spilled between ten and sixteen thousand US gallons of water and sediment after a dam failed from an iron ore mine. Arsenic and mercury polluted the Doce River, arsenic levels were found more than ten times above the legal limit in some places of the river (The Guardian, 2015). Waste production is inevitable during Mining. However, a preventive waste management strategy could have minimised waste production, maximised waste reuse and classified waste by their hazardous degree."

Jan 1, 2016

By Gae On Kim, Ki Baik Kim, Suk Hoon Kang, Tae Kyu Kim, Sanghoon Noh

"Advanced radiation resistant oxide dispersion strengthened steel (ARROS) is being developed as a fuel cladding tube material for future nuclear reactor system applications. The research activities consist of advanced radiation resistant ODS steel development and fabrication technology development of ODS steel structural components. One candidate material with a chemical composition of (in wt%) Fe-10Cr-1Mo-0.5Mn-0.1V-0.25Ti-0.35Y2O3and was selected as representative materials, and this material was named as the advanced radiation resistant ODS steel (ARROSTM).On the basis of this ODS steel composition, an optimized fabrication process of structural components such as plates, sheets and tubes has been established through various process conditions in mechanical alloying, hot/cold working, and heat treatment processes. These R&D activities are expected to contribute to the realization of ODS materials in the future.INTRODUCTIONA sodium-cooled fast reactor (SFR) is being developed at the Korea Atomic Energy Research Institute (KAERI) with a view to economics, safety, reliability, and sustainability. The prototype Gen-IV SFR with a capacity of 150 MWe is under design, and this prototype reactor is scheduled to operate from 2028. For a commercial SFR system application, it is necessary to develop an advanced structural material having both high creep strength and irradiation resistance at high temperatures (Jeong, 2014). Oxide dispersion strengthened (ODS)steel is one of the most promising structural materials because of its excellent creep and irradiation resistance on the basis of uniformly distributed nano-oxide particles with a high density, which is extremely stable at high temperatures under a neutron irradiation environment for a prolonged operating period(Kim, 2016). As the first step, several batches of ODS steel were designed and the candidate samples with a 2 kg scale each were fabricated by mechanical alloying, hot isostatic pressing and hot rolling processes. The mechanical properties of these samples were evaluated. Up to now, two candidate materials with chemical compositions of (in wt%) Fe-10Cr-1Mo-0.5Mn-0.1V-0.25Ti-0.35Y2O3 was selected as representative materials, and these materials were named as the advanced radiation resistant ODS steel (ARROSTM).The next step was to optimize the fabrication process of the ARROS compositions for in-core structural components such as the fuel cladding tubes of a SFR. An optimized fabrication process of fuel cladding tube with a composition of ARROS has been established through various process conditions in mechanical alloying, hot consolidation, hot/cold working and heat treatment processes. Joining technologies of the ODS steel tubes is being developed using solid-state welding such as magnetic pulse welding, friction stir welding and diffusion boding. It is expected that the development of ARROS will contribute to the realization of a commercial SFR with high economics and sufficient safety in the future. In this paper, the study of fabrication process of ARROS structural components is introduced."

Jan 1, 2017

By A. Mykytiuk, I. E. Puddington, W. D. Macleod, F. W. Meadus

"A laboratory-scale continuous procedure for the up-grading of naturally occurring tin ores, based on the principle of spherical agglomeration, is described. High recoveries are indicated. A proposed second stage suggests useful fractionation steps.IntroductionA LABORATORY-SCALE batch process for the upgrading of a tin ore using the principles of spherical agglomeration has already been described (1). This procedure consisted of milling, for about an hour, a precrushed ore with at least 200 per cent water, 0.2 per cent of a reagent such as tall oil (to render the de-sired ore particles hydrophobic) and about 3 per cent of a viscous petroleum oil. The feed material passed an 8-mesh Tyler sieve, and the percentages of re-agents are based on the dry weight of the feed. Du-ring the grinding, the hydrophobic particles transfer into the oil phase to produce coherent semi-solid bodies while the gangue stays preferentially in the aqueous phase. The concentrate can be separated from the gangue easily by a mechanical operation. Using an ore containing about 0.3 -0.5 per cent tin, grades of from 1.5 to 7.0 per cent were obtained by varying the pH of the system. Recoveries fell from about 80 per cent to as low as 50 per cent as the grade in-creased."

Jan 1, 1966

By S. Ando

The fatigue crack growth behavior of magnesium single crystal has been investigated, CT (compact tension) type specimens with different notch orientations were prepared. In the case of notch plane and direction are (1-210) and [10-10], fatigue crack propagates parallel to notch, From TEM observation, it is found that pyramial slips occures at the crack tip. When notch is normal to basal plane, a fatigue crack propagates [0001] and parallel to basal plane depending on stress intensity factor range, In the case of notch parallel to basal plane, a fatigue crack propagates through straight route with some {10-12} twin, Fatigue crack growth rate, da/dN of A- and B- specimen is lower than F-specimen with crack parallel to basal plane.

Jan 1, 2004

By Y. Hayashi, A. Fuwa

To analyze zinc vaporization kinetics of zinc smelting slag in the ISP furnace, reduction reaction rate of zinc oxide from ZnO-FeOx-CaO-SiO2 slag system with CO-CO2-Ar gas mixtures has been measured by a therm o-gravim etric apparatus at various ZnO content, Pco, and temperature. The reduction rate was measured under a chemical reaction control in the initial three minutes where surface zinc content can be assumed constant. Through the reaction rate dependency analysis on ZnO contents, Pco and temperature, discussion has been made on its reaction mechanistic information in terms of rate coefficient, adsorption/desorption mechanism and activation energy.

Jan 1, 2008

By P. C. Lightfoot, J. M. Duke, A. J. Naldrett

"The segregation of magmatic sulphides from mafic and ultramafic silicate magmas, in many circumstances, leaves the magma with a lower-than-normal Ni/MgO ratio, which is characteristic of both lavas erupted from the magma chamber and olivine crystallizing within it. Two end members of the segregation process are discussed; i) batch segregation and ii) fractional segregation.In the former, the critical factor is the magma/sulphide ratio. Computer modelling suggests that where this ratio has been less than 1000, the magma will be recognizable as anomalously low in Ni, due to sulphide segregation, and thus a good target for exploration. In fractional segregation, the critical factors are the proportion of sulphide to silicate being segregated and the degree of fractionation.Samples believed to represent the liquid portion of komatiitic lava f lows from a series of unmineralized sequences in the Abitibi greenstone belt, Canada. Belingwe belt, Zimbabwe, and Barberton Mountainland, South Africa coincide with the sulphide-free fractionation model. They are in marked contrast to samples from the ore-bearing districts of Kambalda and Scotia. Western Australia in which distinct Ni depletion, corresponding to fractionation of olivine plus sulphide in a ratio of between 100 and 200:1 is recognizable. Ni-depleted olivines also mark the sulphide-bearing Dumont intrusion of the Abitibi belt.The Moxie intrusion of northern Maine has distinctly Nidepleted olivines, as does the nearby and petrologically related Katahdin body. In both of these intrusions, the composition of the olivine allows reasonable predictions to be made of the Ni tenors of sulphide showings within them. At Katahdin, the Ni depletion is so widespread that little hope is help out for the presence of economic concentrations of sulphide. At Moxie. the olivine compositions suggest that the best chance of economic sulphides lies in the southern lobe of the intrusion.Ni-depleted olivines also characterize certain rock units within intrusions of the Insizwa complex, Transkei, Southern Africa. Many millions of tonnes of Ni have apparently been removed by sulphides from these rock units, many more than are contained within the single mineralized occurrence so far identified at Waterfall Gorge."

Jan 1, 1984

By Michael K. O’Leary, William D. Coplin

"Risks from political instability and government policies restricting equity ownership, local operations and transfers of payments affect the profitability of foreign mining ventures. More than seat-of-the-pants judgments and old-boy networks are required to anticipate these risks and to take actions appropriate to offsetting them. A system for making political forecasts, called the Prince System, and a series of charts relaying risk s to a production of key minerals will be presented.IntroductionFirm s with extractive operations outside their home country do not have to be told that political stability and government decisions play a big role in the success o f their operations. The takeover of copper firm s in Chile during the Allende administration in 1971 and the recent decision by Venezuela to reduce Reynolds Metals equity share in a smelting operation from 50% to 28% are two examples of hundreds of events that have determined the profitability of extractive operations over the past decade. Both risks and opportunities for international firms seeking to produce and market raw materials are heavily affected by political conditions. While news of political events travel much faster than in the past and host governments are more clever in shaping the risks as well as the opportunities, politics has always been part of the mining business.What has changed is the need to be more systematic in approaching the assessment of political conditions and how it affects business. The increasing costs of extractive operations, the need for long-range planning, the importance of financial arrangements and the world-wide scope of man y firm s' activities require that the assessment be updated continuously and be comparable across different countries and different types of investments. Political risk analysis, the assessment o f macro-political changes and specific governmental decision s on the operations of extractive industries needs to become as systematic and integrated into corporate decision -making as economic analysis has become over the past two decade s."

Jan 1, 1983

By Robin Perry, Claude Bazin

"Discrete transfer functions which use the grinding circuit feed tonnage to predict mass flowrates at reagent addition points in a flotation circuit were calibrated using a dynamic grinding/flotation circuit simulator. Predicted mass flow values are multiplied by reagent addition ratios to obtain actual reagent flow. The transfer functions are currently integrated into the distributed control system of Les Mines Selbaie.IntroductionThe development of adequate tools for the control of flotation processes is a continuous challenge. Since the early 1970s there have been numerous publications dealing with practical aspect of control of flotation processes. Most plants use a combination of feedback and feedforward controls to reduce the effect of the following flotation process disturbances (McKee, 1991):• changes in throughput;• changes in feed grade;• changes in particle floatability (size, liberation, surface oxidation ... ); and • deliberate changes of setpoint;Feedforward control manipulates variables such as reagent and/or air flow rate to attenuate the effect of disturbances such as changes of feed rate and mineral content. The feed forward strategy is driven by measurements of these disturbances. Feedback control is used to maintain process variables to targeted set-points of concentrate or tails grades. The feedback control action is driven by deviation from the set-point, caused by a deliberate change of set-point or disturbances.This paper proposes a method to improve feed forward control schemes by the addition of a simple model for solids transportation. The feedforward strategy considered in this paper is the ratio type, in which the manipulated variable is changed according to a predefmed ratio between this variable and the measured disturbance. A typical example is the ratio of the reagent addition to mass flow of ore.The paper reviews the state of the art in feed forward control strategy applied to flotation processes and describes the method used for predicting mass flow rates. The last section shows an application of the method in the Les Mines Selbaie flotation circuit."

Jan 1, 1994

By Wei Wei

Mining induced ground movement and/or stress redistribution could cause ground instability issues. This is particularly true when the extraction of large stopes is done with one or two large production blasts. Often enough, it is the nearby mine development like haulage drifts and cross cuts that are influenced the most by production blasts. Proper and timely mitigation of ground control issues due to stress redistribution is required. This is usually done by drift rehabilitation involving the installation of secondary support system in the affected areas of the mine development which include; slashing, wire mesh, and in some cases the use of shotcrete liners. It is imperative that such rehabilitation be implemented to the mine infrastructure in a timely manner in order to avoid aggravated ground control problems and production delays. If the real time performance of the support system is captured, it would be possible to determine the timing for rehabilitation job. Birchtree Mine in Thompson, at the Vale Manitoba Operation, has begun mining the 84 Deep Orebody. One of the identified risks is the stability of the crusher room under mining induced stress redistribution. It is proposed to use the U-Cell technology to monitor the primary support system performance (rebar bolts and extension bolts) and monitor the real time performances of the bolt axial loads. The U-Cell technology is a 7-inch long, coupler load cell that is screwed onto the threaded portion of a rock bolt prior to installation. Rehabilitation in the vicinity of the crusher area where U-Cells are installed is recommended when the bolts have reached 70% of their yielding capacity. Catastrophic ground failure can be avoided by adding secondary support in a timely fashion. This paper presents a case study at Birchtree Mine in Thompson Manitoba, where the performance of primary ground support system is monitored and recorded during production.

Jun 1, 2012

By G. M. Hughes

"400 cubic foot Agitair Flotation Cells are in use at Sherritt Gordon's Fox and Ruttan Mine Cu-Zn concentrators. The 4 impeller model No. 120, used at the Fox Mine Operation, appears to offer superior agitation and aeration qualities compared to the single impeller model 120A, in use at Ruttan. The advantages of the model 120 are most significant with ores of high specific gravity and coarse grind.IntroductionSherritt is using 400 cubic foot Agitair flotation machines at both the Fox and Ruttan Mine Concentrators.At the 3000 tpd, Cu-Zn Fox concentrator, 18 model 120 machines have been in operation since May, 1969.The 10000 tpd, Cu-Zn operation at Ruttan utilizes 49 model 120A machines. The plant started operation in May, 1973.The 4-impeller model 120 flotation cell has been marketed by Galigher since the early 1960's but the single impeller model 120A is relatively new.Model 120 Agitair -Cell DataThe Model 120 (Dwg. 1) has floor dimensions of 101 x 10' and a lip height of 2~ to 4 feet to provide up to 400 cubic feet of volume. This machine is shown with a froth crowder and stabilizer plates which are optional.Each motor drives two agitators. 20 HP is recommended by Galigher but 25 HP is more realistic with massive sulphides. The SG of ?ox ore is about 3. 6.The Model 120 can handle up to 600 cubic feet of air per cell at 2 psig which requires 5-6 HP at the blowers. Air volume to each impeller is controlled by a valve from a main header.During the first 3 years of operation at Fox there were few mechanical problems with the 120's."

Jan 1, 1974

By J. Someehneshin

Nowadays along with population growth, industry development, consumption of mineral resources and the fact that the reserves on hand are running out, the depth of surface and underground mines for further exploitation are increasing. During recent years, in underground mining, the block caving method for low-grade and large-scale deposits has shown a growing rate of application. This method is very cost effective and economically affordable. The dimensions of blocks are one of the most important parameters which should be taken into account since it has been proved to have a great deal of effect on technical issues such as commencement of caving and mine design. Proper calculation of the length and width for a block in this method leads to proper caving and discharging which are the most important stages. Therefore, in this method, the calculation of the optimized dimensions (length and width) of blocks is not only important but also directly helps the productivity of extraction. In this study, firstly for the purpose of facilitation, some assumptions were considered and having used these assumptions for estimation of optimized length and width of block, a relationship based on rock mechanics and physics was explored. Furthermore, some necessary details were added to the said relationship and finally, it was transformed into an inequality. Solving this inequality provides us with the optimized length and width of the block. The explored relationship was analyzed with MATLAB software and the graphs thereof were drawn. In these graphs, each time one of the input parameters has been drawn up in a logical range so that it could be compared with previous states.

Aug 1, 2013

By Greg Yuriy

This paper discusses research carried out by the Laurentian University Mining Automation Laboratory (LUMAL) in the field of discrete-event simulation of mine equipment systems and reliability assessment of these machinery using genetic algorithms. The AutoMod simulation package, from Brooks-PRI Automation Inc., is used in this research. It is a 3-D discrete-event simulation/animation software tool for creating realistic depictions of manufacturing and materials handling systems. Discrete-event simulation involves modeling of real-life systems based on variables and events which occur or change at distinct points in time. In our case, a two level, multi-drift sublevel stoping model was created in AutoMod for the simulation of the equipment fleet employed in the development cycle (drilling, explosives loading, blasting, materials hauling, ground support) of a typical underground mine in the nickel mining region of Sudbury in Ontario, Canada. The equipment primarily considered in the simulation is Load-Haul-Dump (LHD) vehicles (scooptrams), drills, explosives-loaders and roof bolters. The purpose of the simulation study is to assess the impact of equipment failures to mine?s production throughput. In more detail, using Mean Time Between Failures (MTBF) data of scooptrams derived from a reliability assessment model based on genetic algorithms, LHD failures are incorporated into the simulation model. These failures cause production interruptions to the development cycle and consequently loss of hauling capacity. This paper will indicate the significance of equipment failures to a mine?s production and suggest a methodology based on the combination of discrete-event simulation and a predictive reliability assessment model using genetic algorithms for the study and analysis of mine equipment systems.

May 1, 2003

By Dallas Bienhoff

Boeing Study Team Participants Andrew Daga & Associates American Aerospace Advisors Hamilton Sundstrand Harris Honeywell ILC Dover Lunar Transportation Systems Oceaneering Orion Propulsion SICSA Thin Red Line USA LSSCA BAA Topic 2: MFHE Definition Minimum Functionality Habitation Element Deployable Habitat DHE Update The Path to Growth

May 1, 2013

By Matt Schuett

Antamina Mine Facts • Surface Water Design Principles • Drainage Areas • SEDCAD Modeling • Impacted Runoff Collection • Clean Runoff Collection • System Flexibility • Outfall Construction

May 1, 2004

By Jacek Paraszczak

Possibility to move human workers away from dangerous places ?enhanced safety and improved working environment; ? Increase of actual operational time: ? Less losses due to shift changes, regulatory breaks, blasting periods, ventilation after blasting, etc.; ? Possibility to work in extremely dangerous conditions where man-operated machine could not be used (for example: ST-14 loader in backfilling operations in the Kemimine, following roof collapse). Reduction of the production cost through: ? Lower maintenance cost (less damage due to operator?s mistakes and no machine abuse); ? Higher productivity and effectiveness of the equipment (less machines to meet production targets, less operators required, lesser maintenance cost...). ? Although personnel health and safety are key drivers behind autonomous operation of mobile equipment in U/G mines, with significant capital and operation costs one expects to achieve: ? Productivity higher, or at least equal to that offered by man-operated equipment and systems; ? Lower production cost. Therefore, high effectiveness of the autonomous equipment is crucial to succeed.

May 1, 2010

By Walter Valery, Sergio Vicuna, Roberto Valle, Hamer Arevalo, Ben Burger, Lui Vargas, Alex Jankovic, Jim Seidel, Eduardo Nozawa

This paper describes the design, the first three years of operation and optimization of a large, single stage SAG mill at Minera Yanacocha’s Gold Mill facility located in northern Peru. The Gold Mill was commissioned in March 2008 with a 32’ x 32’ EGL, 16.5MW single stage SAG mill, to process 5 million tonnes per annum high grade oxide Au/Ag ore. Operational control, feed size distribution, grinding media, mill liner, grate and pulp lifter optimisation have allowed the mill to operate 15-30% above design throughput rates, but with a product P80 coarser than design. As part of the optimization, full grinding circuit surveys were conducted. Historical operating data and survey data were analyzed and used to evaluate possible circuit changes and determine alternative operating strategies. A number of changes were implemented which allowed the SAG mill to operate similarly to a large ball mill and achieve finer mill product that was closer to design. This paper summarizes life to date data analysis and improvements made by Minera Yanacocha as well as the grinding circuit optimisation study conducted by Metso Process Technology and Innovation.

Jan 1, 2012

By Martin Bergeron

Producteur d?or de taille intermédiaire Mines Aurizon Ltée Bureau-chef àVancouverMine et projets localisés au Québec2

May 1, 2011