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By Q. Ricoux, F. Goettmann, A. Maihatchi

"Electrodeposition processes are widely used in the metallurgical industry to produce, extract and refine metals from various feed materials. However, raw materials used to provide non-ferrous metals often contain high amounts of iron. In the presence of iron, while metals are plated at the cathode, electrowinning processes produce corrosive and highly oxidative ferric ions at the anode that are harmful for the process sustainability. In fact, these ferric ions cause dramatic current efficiency loss, induce high maintenance expenditures to limit the corrosion of devices and it results in the formation of impure and dendritic deposits on the cathode. Consequently, the management of iron in electrodeposition process became a major issue in non-ferrous metals production. Actually, numerous methods have been developed to limit the ferric ion concentration in the electrolyte or, at least, to limit its harmful effect. Many methods aim to limit the iron(III) concentration in the electrolyte, generally by coupling electrowinning to extraction process such as solvent extraction (SX) (Bender & Emmerich, 2015), ion exchange (IX) (Gula, Dreisinger, & Horwitz, 1996) or cementation (Kust, 1979) processes to remove ferric ions. Other routes consist of (i) using the ferric ions oxidant properties to leach raw materials, either directly in the electrolytic cell (Fanta & Tributsch, 1975) or through a secondary circuit (Cain, 1950), or (ii) reducing ferric ions through periodic reversal of direct current to enhance the formation of Fe2+ (Loutfy & Bharucha, 1980). On the other side of the spectrum, papers discuss methods to valorize the iron from by-products of the non-ferrous metal industry, that generates vast quantities of iron containing wastes (A. Agrawal, Sahu, & Pandey, 2004). Many studies on iron electroplating and electrolytic iron production from ores have been carried out (Cain, 1950; Mostad, Rolseth, & Thonstad, 2008), but very few have been conducted on waste or by-products. Therefore, we propose to build on the previous literature review to develop a process for the production of electrolytic iron from by-products.INTRODUCTIONNon-ferrous metals and their alloys are used in a large variety of applications. Aluminum and titanium are used for their strength, light weight and corrosion resistant properties in structural applications. Copper has been used in various applications requiring high thermal and electrical conductivity, as kitchen products and electrical wires. Nickel and zinc are commonly used as plating materials; nickel offers a wide range of working temperature and zinc is used for steel plating. Gold, silver, and platinum group metals are used in electrical/electronic applications, jewelry and chemistry as catalysts."

Jan 1, 2016

By C. Chongo, L. Little, Q. Mclennan

Since commissioning in 2005, First Quantum Minerals’ Kansanshi Mine in Zambia has produced over three million tons of copper and 1.8 million ounces of gold from a deposit with highly varied copper mineralization. The processing plant is complex with three independent flotation circuits, gold gravity concentration, atmospheric and high pressure leaching, solvent extraction, and electro-winning. For the first ten years of operating the plant, copper mineralogy was inferred from total copper and acid soluble copper assays, and various misconceptions developed about the mineralogy which impacted operational strategy and project decisions. In 2015, an on-site mineralogy section was set up with an Automated Scanning Electron Microscope, the Zeiss MinScan. This instrument has provided detailed mineralogical data that have debunked some of the mineralogy myths that had developed, highlighting the key underlying issues affecting processing performance. This has enabled the development of projects targeting losses of specific copper minerals in defined size classes, unlocking significant value. This paper describes some of the early misconceptions around mineralogy at Kansanshi processing plant, outlining projects that have benefitted from understanding copper mineral distribution. Learnings from Kansanshi are to be applied at other FQM sites, with a similar mineralogy program being set up at the Cobre Panama project. INTRODUCTION The deposit Kansanshi Mine is located in the North Western Province of Zambia, and it has been the largest copper producer in Africa for over a decade. The deposit occurs within a broad northwest trending antiform that can be traced for 12 km, hosted in a zone of complicated faulting, abundant vein injection, breccia development and down-dropped rock units that lies within Kansanshi’s mining license. The copper mineralization within the deposit is predominantly vein-hosted, although some is strata-bound, occurring in thin bands and veinlets parallel to foliation, and some is disseminated associated with albite-carbonate alteration (Gray, 2015). Supergene enrichment has led to significant variety in the copper mineral speciation. This alteration is complex, and has not followed the text-book principles with a neat layer of supergene mineralization overlying fresh hypogene ore. Rather, the occurrence and extent of oxidation and supergene enrichment is highly irregular throughout the deposit, sometimes occurring at significant depth in localized pockets and along fault lines. Gold mineralization tends to follow the copper within the deposit, but it is dominated by coarse-grained, free-milling native gold. The extent of copper oxidation – measured as the fraction of total copper that assays as acid soluble – is used to classify ore into three main ore types, named Sulphide, Mixed, and Oxide, which are then fed to three different primary crushers for processing in independent circuits.

Jan 1, 2019

By Rachel S. Prudhomme, Michael L. Jeremic

"The consolidation of mine backfill by free zing is a concept which has been under study in the mining engineering laboratories at Laurentian University during the past three years. The proposed underground application of freezing involves the artificial freezing of in-situ backfill by means of a refrigerated brine solution which would be circulated through a circuit off freeze pipes. The most interesting findings to date are: (I) The uniaxial compressive strength off frozen fill is considerably higher than that of cemented fill in a ratio of 20:1 (aggregate to cement), and (2) load deformation characteristics of the frozen fill suggest that a higher ice content results in more brittle failure and that samples which have initially failed can still support up 10 one-half the ultimate load without additional failure.Although at this early stage a derailed economic analysis of the procedure has not been possible, a general evaluation of the costs involved suggests that the method could be competitive with the hydraulic placement of cemented backfill. Results obtained from laboratory investigations indicate that the freezing of backfill is a structurally feasible option .IntroductionGround consolidation by freezing is based on the principle of transformation o f water contained in an aggregate-slurry into ice, which act s as a binding agent between the bulk particles, and which results in the transformation of a granular soil into a ""rock -type"" material. The abrasive nature of the particles enhance s the strength o f the ice by providing internal friction. As a result of this internal friction, the chances of plastic flow of the frozen mass when in a loaded condition are reduced(1). T he strength of a frozen aggregate is al so dependent on the grain shape of the aggregate particles which may or may not promote particle interlocking(2) and on the temperature since, below the freezing point of the water/aggregate mixture, the strength of the frozen mass increase s with decreasing temperatures.In the shaft sinking industry, artificial freezing of loose , unconsolidated soils has been in practice for several decades. Shafts for Saskatchewan 's potash industry have been sun k to depths of 3000 feet by employing artificial freezing to stabilize the Blairmore Formation(3). The common procedure for freezing ground for shaft sinking is summarized as follows(4,5): I) 150 mm diameter bore holes spaced on 1.5 m centres are drilled in a circular pattern with a radius of 1.5 m outside the periphery of the proposed shaft."

Jan 1, 1985

By L. Nastac, Y. Xuan

"The metal-matrix-nano-composite (MMNCs) in this research work consists of an A356 alloy matrix reinforced with 1.0 wt. % SiC 50 nm diameter nanoparticles that can be dispersed within the molten alloy matrix via ultrasonic stirring technology (UST) and induction melting and stirring processing. The necessary ultrasonic parameters to achieve the essential cavitation for adequate degassing and refining of the A356 alloy as well as the optimum fluid flow characteristics for uniform dispersion of the nanoparticles into the A356 alloy matrix have been investigated in this study by using computational fluid dynamics (CFD) modeling with a magneto-hydro-dynamics (MHD) model and an UST cavitation model.The MHD model accounts for turbulent fluid flow, heat transfer and solidification, electromagnetic field as well as the complex interactions between the solidifying alloy and nanoparticles by using ANSYS Maxwell and ANSYS Fluent Dense Discrete Phase Model (DDPM) and a particle engulfment and pushing (PEP) model.INTRODUCTIONAluminum matrix nanocomposites can offer outstanding properties, including low density, high specific strength, high specific stiffness, excellent wear resistance and controllable expansion coefficient, which make them attractive for numerous applications in aerospace, automobile, and military industries field (Bozic, 2010, De Cicco, 2009, Elshalakany, 2014, Goh, 2006, Jia, 2013 and 2015, Liu, 2014, Reihani, 2006, and Su, 2010).As shown in literatures (Aki, 1999 and Mussert, 2002), it is highly advantageous to use nano-sized ceramic particles to produce metal matrix nano-composites (MMNCs) since similar ductility and higher strength with the metal matrix can be achieved. Currently, there are several fabrication methods of MMNCs, including mechanical alloying with high energy milling (Chen, 1997) , ball milling (Filho, 2003), nano-sintering (Groza, 1999), spray deposition, electrical plating, sol-gel synthesis, laser deposition, etc. The mixing of nano-sized ceramic particles is normally lengthy, expensive, and energy consuming.Ultrasonic Stirring Technology (UST) has been extensively used in purifying, degassing, and refinement of metallic melt (Jian, 2005, Khalifa, 2008, Eskin, 2002, Xu, 2004, and Meek, 2006) mainly because introducing the ultrasonic energy into a liquid will induce nonlinear effects such as cavitation and acoustic streaming. SiC nanoparticles are widely used as reinforcement particles due to their relatively good thermal and chemical stability. Ultrasonic vibration can improve the wettability between the reinforced nanoparticles and the metal matrix (Lan, 2004, Cao, 2008, and Yan, 2011), which will assist to distribute the nanoparticles more uniformly into the metal matrix. Ultrasonic cavitation in liquids causes high speed liquid jets of up to 1000 km/h. Such jets press liquid at high pressure between the particles and separate them from each other (Hielscher, 2005)."

Jan 1, 2016

By James J. Roettger, Robert J. Mitchell

"The results of a series of model stope pours designed to investigate working pressures on bulkheads during hydraulic pouring of classified tailings backfill are reported. Total bulkhead pressures and fill water pressures were monitored under the condition of a fully saturated backfill. Similitude of the model testing is discussed and equations are developed to estimate bulkhead pressures under prototype conditions. The model results show that good base drainage, combined with a bulkhead setback, can reduce the expected bulkhead pressures to values such that timber or concrete block structures should be capable of supporting a saturated backfill. Introduction Bulkheads are used in underground running operations to block drift openings in order that hydraulically placed sand backfill can be contained in stope pours. Whenever possible, the sand fill is designed to have sufficient percolation rate so that excess hydraulic transport water will gravity drain out through the bulk headed drifts. This avoids costly decanting systems. Early bulkhead design assumed that the bulkhead pressure could be as high as 0h = Hy where H is the fill height and ""y is the saturated unit weight of the fill (Thomas et al., 1979)(1). A typical design pressure for a 50 m fill height would be 1250 kPa giving a design force of 12,500 kN on a bulkhead located in a drift of 10m2 in area . Typical bulkheads were 1 m thick heavily reinforced concrete structures formed and poured into a notched drift. Not only were these expensive structures but the associated problems of inside drainage systems and curing time delays increased production costs. As experience with bulkheads for large bulk pours increased and fill pressure measurements became available [see, for examples, Libby et al., 1975(2), Askey et al., 1978(3)] , 'free drainage' timber and concrete block bulkheads were designed. Substantial savings have been realized using these types of bulkheads but greater engineering design and monitoring of backfill pours is necessary to ensure that backfill pressures do not exceed the bulkhead design pressures.The effective and total stress components of fill pressure, the engineering concepts associated with the 'free drainage' design and some detailed design considerations have been discussed by Smith and Mitchell (1982)(4) . It is important to the safe use of these designs, however, that the basic engineering concepts be demonstrated and communicated to those responsible for the day-to-day backfill operations. This paper describes and explains observations from a series of model studies designed to measure bulkhead pressures in a saturated fill."

Jan 1, 1984

By Junto Nishiwaki, Shinji Kumai

"Mechanical and physical properties of the impact welded dissimilar metal joints are controlled by joint interface morphology. An intermediate layer (IML) is often formed at the joint interface and this deteriorates the interface quality in some metal combinations. Numerical and experimental studies were performed in order to examine the formation mechanism of the wavy interface and intermediate layer for explosive welded Al/Cu dissimilar metal joints. The impact welding process consists of (1) high-speed oblique collision of metal plates, (2) metal jet emission and large deformation and temperature increase at collision point and (3) rapid cooling at the joint interface. Euler-Lagrange coupling method, smooth particle hydrodynamic (SPH) method and modified laplacianFoam (LF) method were linked together to simulate a series of processes from (1) to (3), and the final interface morphology including the formation of IML was reproduced. The wavy morphology (wave-height, wavelength) and the position and composition of IML formed at the joint interface of Al/Cu joints were quantitatively in good agreement with those reproduced by numerical analysis. Our simulation results are useful for the control of the interface morphology, reduction of the amount of IML, and improvement of the mechanical properties of the impact welded dissimilar metal joints.INTRODUCTIONImpact welding is a kind of solid state joining method providing extremely high joint strength for both similar-and dissimilar metal combinations. Explosive welding and magnetic pulse welding are representative methods to achieve the impact welding. By a high-speed oblique collision between two metal plates, a metal jet is emitted from the collision point. The metal jet can remove any oxide films and contaminations on the plates and produce an active refreshed surface. Consequently, good metallurgical bonding can be achieved even for dissimilar metals (Crossland, 1982). Solid metals deform like fluids under the high pressure condition at the collision point and characteristic wavy interface is formed. In addition to the wavy interface, an intermediate layer (IML) is often formed at the joint interface in some metal combinations. Elimination or reduction of the amount of IML at the joint interface is desired since the excessive IML formation along the joint interface causes a large reduction in physical and mechanical properties. Formation of IML is considered to result from characteristic thermal history at the joint interface including partial melting due to the local temperature increase and successive rapid cooling behavior at the joint interface. In order to control the IML formation at the joint interface, it is necessary to reveal both heating and cooling processes at the joint interface. However, it is impossible to observe the phenomenon occurring at the joint interface and also difficult to investigate the temperature change at the joint interface directly during the impact welding. Therefore, simulation or numerical analysis is indispensable to overcome this problem. In the present study, the explosive welded Al/Cu joint, which is prone to form IML at the joint interface, was selected for the research. By using a newly developed numerical analysis method, not only the formation process of wavy interface, but also the local temperature increase and successive temperature decrease at the joint interface were reproduced. The formation process of IML was investigated by using both numerical analytic and experimental results."

Jan 1, 2018

By C. B. Ndimande, C. Ntsele, M. Lisso, L. Arlow

"In the processing of UG2 platinum ore, stirred milling technologies are dominating regrind applications that require grinding the particles to P80s’ in the region of 45 µm. For this application stirred mills are 30–40% more energy efficient and require a smaller foot print compared to traditional tumbling mills. In this work a study was carried out using a batch pin mill and three scales of Stirred Media Detritors. A laboratory scale pin mill, a pilot scale Stirred Media Detritor with an installed power of 18.5 KW and two industrial scale Stirred Media Detritors in continuous operation, with an installed power of 355 KW and 1,100 KW were used. The industrial scale SMDs were in the secondary grinding section of a mill floatmill float (MF2) UG2 processing plants. The tests were focused on assessing the effect of feed rate and percent solids on power consumption and product fineness at lab scale, floatation response of the SMD product at pilot scale and on an industrial scale, the effect of feed rate on energy consumption and product fineness. The measurements obtained were feed flow rates, mill power and from the samples cut, particle size distribution of both feed and product. Specific energy was observed to increase with increasing percent solids over the 30wt% to 80wt% studied. Floatation response tests of the pilot scale SMD products show improvement in grade. Specific energy and reduction rations are observed to decrease with an increase in feed rate.INTRODUCTIONThe purpose of comminution in most mineral processing applications is to liberate the valuable minerals from gangue so that they can be recovered in subsequent separation stages. Most precious and base metal plants treat low grade fine-grained ores which require a higher degree of size reduction to yield the necessary degree of liberation (Partyka & Yan, 2007). Many authors have shown that the relationship between product size and grinding energy consumption is exponential, the finer the product from the comminution device, the higher the energy consumption (Gao & Weller 1993; Napier-Munn, Morell, Morrison & Kojovic, 1996; Jankovic, Valery & La Rosa, 2003). The suggested reason for this kind of relationship is that smaller particles have fewer flaws and higher strength than larger particles. Particles with fewer flaws and higher strength require higher energy for breakage to occur. One of the challenges most plants face is that of efficient energy utilisation in the liberation of the mineral from these complex ores. Conventional tumbling mills are not energy efficient in fine and ultra-fine grinding applications because some of the energy is spent on moving the charge and does not go directly into breakage. Stirred mills have been found to be about 30% to 40% more efficient and require a smaller foot print compared to traditional tumbling mills for regrind applications that require product size with P80s’ in the sub 45 µm regions (Radziszewski & Allen, 2013). Stirred mills are able to produce fine product because they can achieve a high number of stress events per unit time and volume compared to tumbling mills (Kwade, 1999a). To minimise energy usage without compromising product quality, the mining industry has adopted stirred milling technologies for fine and ultra-fine grinding (Radziszewski & Allen 2014; Kwade, 1999b). The south Africa platinum group metal (PGM) industry alone had over 40 stirred media mills installed by 2011 (Rule, 2011). Of that 40, 13 were in the ultra-fine grinding (UFG) application and the rest in main stream inert grinding (MIG)."

Jan 1, 2016

By J. Sadaki, G. Dodbiba, S. Murakami, T. Fujita, S. Matsuo, H. Ono, K. Okaya

Printed circuit boards (PCBs) from discarded personal computer (PC) and household appliances were crushed by mechanical crushing or water explosion to remove mounted parts. More parts were stripped from PCB for PC composed of epoxy resin than from PCB for household appliance composed of phenol resin. In an attempt to raise the copper grade of PCB by removing other components, a carbonization treatment was investigated. The crushed PCB without surface-mounted parts was carbonized under a nitrogen atmosphere at 1073K. After screening, the char was classified by size into oversized pieces, undersized pieces and powder. The copper foil and glass fiber pieces were liberated and collected in undersized fraction. The copper foil was liberated easily from glass fiber by stamping treatment. On the other hand, tantalum capacitors were collected from mounted parts. The tantalum-sintered bodies were separated from molded resins by heat treatment at 723 to 773K in air atmosphere and screening of 0.5mm. Silica was removed and 70% of tantalum grade was obtained after more than 823K heating and separation.

Jan 1, 2011

By R. Heikkilä

As a part of a large research and development program in Finland, a system calibration for an UAV measurement method having practical experiments in a Jorvas Railway Yard design and construction project. The Railway yard construction are was measured using an UAV measurement device by Smartplanes (Smartone) and using some reference points measured by a GNSS device. The measured data was cleaned, combined and adjusted through Least Squares Optimization using the software developed by a Finnish company Pieneering Oy. As references, two different laser scans as well as total station surveys were used. For applicability evaluation, the accuracy of measurement, the reliability of measurement, and the economy of measurement were used. Based on the comparisons, the achieved precision of the UAV measurement was high, instead the accuracy of measurement was not sufficient in this case. The principle of this photogrammetric measurement includes a lot of redundant observations making it possible to achieve a high level of reliability. The economy in this Railway Yard Design project was not able to achieve.

Aug 1, 2013

By C. E. Cairnes

The Slocan mining camp in Kootenay district; British Columbia; has long been noted for the great number of its silver-bearing deposits; and for the success that has; in many instances; attended their development. The orebearing area lies east of Slocan lake and mainly within a radius of 6 to 8 miles of the mining town of Sandon. Within this limited area 135 or more properties have shipped ore in quantities of from 100 tons or less to more than 500; 000 tons; and with a total value in silver; lead; and zinc ranging from a few hundred dollars to well over $10; 000; 000. Of the three metals; silver has easily ranked first in value; with lead second and zinc third. Zinc production; however; made slow progress in the early years; and with . the exception of the Lucky Jim mine; and a few others where high-grade ore could be readily hand-sorted; was a detriment to the silver-lead ores until improved methods of separation enabled it to take an important place in the mineral production of the Slocan.

Jan 1, 1954

By Gheorghe Vieru

Security and safety due to environmental impact as well as the radiological consequences during the uranium mining operations, tailings management, uranium processing, disposal of waste in conventional landfill sites are matters of great importance. The Uranium National Company (CNU) from Romania is responsible for all aspects belonging to the management of the entire Romanian uranium industry- the uranium ore extraction, transport and processing of uranium ore, concentrates processing, as well as disposal of sterile ore and waste. The paper will presents specific safety problems related to the identification and evaluation of potential environmental risks, as well as possible radiological consequences associated with the disposal of sterile and the uranium processing waste resulting from processing of the uranium ore. Computer codes will be used, such as IAEA INTERTRAN II and RADTRAN 5. It is also to be noted that this paper considers the main results of the scientific research carried out by the main author as CSI (Chief Scientific Investigator) for Romanian Research Contract on NORM concluded with IAEA Vienna.

Aug 1, 2010

By . A. C. Atenas

Control of arsenic in the Potrerillos' Refinery electrolyte has been obtained by withdrawing a bleed stream of circulating electrolyte and ensuring the ratio of [O]/[As] in the cast anodes is maintained between 0.9 and 1.0. In order to achieve this control the anode oxygen must be adjusted, depending on the arsenic level in the cast anodes. It has been necessary to modify the time of the reduction step in the anode furnace refining process. Control of this ratio has permitted electro refining of anodes with high levels of arsenic, up to 3000 ppm, while minimizing the volume of electrolyte that must be removed for impurity control so as not to affect the copper concentration in the electrolyte. However this control strategy is not useful when the arsenic concentration in the cast anode is too high, because it is limited by the maximum oxygen concentration allowable for a good quality anodic. Costs have been reduced in anode furnace refining because it is no longer necessary to use alkaline flux injection to remove the arsenic in cast anodes.

Jan 1, 2007

By M. C. Bluteau, G. P. Demopoulos

Arsenic reports in the effluents of many non-ferrous metallurgical operations. The production of scorodite, a crystalline ferric arsenate, is considered as an attractive option for the fixation of arsenic from aqueous effluents. However, scorodite solubility and long-term stability in the pH region of interest for tailings disposal have not been thoroughly investigated. In this study the long-term stability of scorodite in the pH 5 to 9 region and the mechanism of scorodite dissolution were studied. Construction of eh-pH diagrams indicated that scorodite stability is highly dependant on the nature (stability) of co-existing iron-hydroxide/oxyhydroxide. It was also found that when scorodite dissolves, a ferrihydrite phase having very small particles size (nano-scale) forms and that the growth and crystallization of this material are delayed by the presence of arsenate even under accelerated (75°C) ageing conditions. Around neutral pH and ambiant temperature (22°C) scorodite seems to reach an equilibrium with ferrihydrite after 48 weeks yielding soluble arsenic concentrations < 5 ppm.

Jan 1, 2004

By Lorna Ortiz-Soto

A series of titiania- and silica-supported Au, Pt and Pt-Au catalysts prepared through different synthetic routes have been investigated in terms of their structural properties, adsorption of CO, and catalytic activity for the selective catalytic reduction of NO by propylene and the oxidation of and CO. Catalysts prepared by incipient wetness impregnation from individual Pt and Au precursors, exhibited characteristics very similar to those of monometallic Pt catalysts. This behavior is consistent with a model in which the two metals remain segregated due to their miscibility gap, and only Pt participates in the adsorption of CO and the reactions under consideration. In contrast, catalysts prepared from a Pt2Au4(C=CtBu)8 organo-bimetallic cluster precursor exhibited different behavior both in terms of CO adsorption and their catalytic activity for the three reactions examined. The combination of the kinetic, spectroscopic and structural characterization data suggests that in this case Pt and Au remain intimately mixed in the form of Pt-Au bimetallic particles, and that the presence of Au modifies the behavior of Pt.

Oct 1, 2003

By Owen Owens, W. P. Armstrong

The process of arriving at the size and grade of: (a) a newly-discovered body of mineralization, (b) a potential ore resource, (c) an orebody proposed for mining, or (d) the ore reserves in a mine, requires fundamental geological, and geometrical determinations as well as physical and chemical analyses. This paper outlines geological and geometrical features considered critical, in the authors&apos; experience, in realistic reserve determination. These are discussed under the headings "The Four Cs". They include the Character, type or nature of the mineralization; the Continuity of various types of mineralization in the deposit; various key concerns in the Calculation besides the mathematics; and the Classification section which refers to basic considerations in classifying a mineral estimate. It is suggested that the responsibility for the calculation of a Resource or Reserve should be that of a geologist experienced in the ore type under review. Further, it should be the responsibility of the board of directors of the company owning the deposit to ensure that a sufficiently experienced person is chosen to carry out the process.

Jan 1, 1993

By G. J. Hawkes

"We all know that every man who works for us should have a thorough knowledge and understanding of his responsibilities. But how about ourselves? Du we have a thorough knowledge and understanding of our own responsibilities as Mill Superintendents?I once had an occasion to say to a Manager that I did not know something was my responsibility and he replied with suitable emphasis ""Everything inside those four walls is your responsibility"". That makes the extent of our responsibilities clear but does not give us a check list to keep an eye on as we do our job from day to day.What are our responsibilities? I suggest they are the following:1. Developing and maintaining efficient operating and maintenance crews.2. Milling the required tonnage.3. Recovering the economical maximum amount of gold.4. Keeping costs at the economical minimum.5. Seeing that the figures are reasonably accurate for tonnages, assays, production, losses, and costs.6. Preventing accidents.7. Preventing fires.8. Maintaining the equipment and building and keeping them clean and tidy.9. Enforcing company rules and regulations."

Jan 1, 1965

A series of small scale tests have been conducted to evaluate the effect of micro-fracture development, imposed by blasting, on the material properties of the rock as well as its resistance to crushing and grinding. The uniaxial compressive strength, tensile strength, Poisson?s ratio, P-wave, Swave velocity, point load test index, crushing and grinding work indices were evaluated for samples without any blasting load and for samples which had received a variety of blast loads ranging from a single impact with low strength detonating cord, to combination of impacts at different times and significant impacts with powder factors close to those used in practical blasts. It was shown that the rock mechanics parameters change even at low impacts, suggesting easier crushing of the rock. Damage values appear to be affected by timing as stress wave superposition affects the damage process. Fragmentation is achieved at higher impact levels while work index modification of the fragments is also observed when high powder factors are used, suggesting improvements in grinding.

May 1, 2003

Deformation is a critical indicator required to evaluate the structural safety, stability, and integrity. For example, the deformed shape of a building structure is a key parameter that needs to be measured and tracked during laboratory testing or post-disaster inspections. However, existing techniques used for the deformation measurement and tracking do not have all the desirable characteristics, such as: reliability, accuracy, low-cost and simplicity of tools installation. In order to address this issue, a novel method has been proposed in this study. The method consists on using the image processing technique to automatically measure and track the deformations of concentrically braced frame (CBF) structures. Accordingly, the critical points in a CBF structure are first identified and the topological configuration of the structure is retrieved. The points and topological configuration characterize the basic shape of the structure. In this way, the deformation of the structure can be determined by measuring and tracking these points and their topological configuration. To show its effectiveness, the proposed method has been tested against the manual deformation measurements.

Aug 1, 2013

By T. I. Kunkel

The economic prosperity of many Canadian communities depends on resource extraction within the traditional territories of Indigenous people. The geographic sites where these resources are situated are also areas where these Indigenous people have sustained themselves for millennia through hunting, fishing, trapping, and gathering activities. These traditional activities provide not only sustenance, but also cultural and spiritual values, and the ability to transmit oral Indigenous cultures and customs from generation to generation. The multimillion dollar revenue mine project proposed within the Cariboo Chilcotin region of British Columbia is situated geographically in a location which has sustained the Tsilhqot?in people for millennia. However, this group of people have important social and cultural values nested within the traditional activities at this location. These values are typically not at the forefront of resource development. Using Indigenous research and grounded theory, this research paper briefly outlines Aboriginal values of the First Nations communities within the Cariboo Chilcotin region and some lessons learned from the Tsilhqot?in people during the environmental assessment of the mine proposal.

Aug 1, 2013

By R. W. Nice

"For many decades the incidence of a highly active graphite-like ore has plagued the McIntyre mine. This ore acts as a precipitant of the gold complex immediately upon formation of this complex. The gold is subsequently discharged with the tailings.Many different methods have been devised by various researchers all of which proved inapplicable for the McIntyre problem.Recently, McIntyre personnel, through their own research, developed a flowsheet. This circuit should give an overall recovery of 36% which is below the 94% experienced in the mill at present. Therefore, less revenue would arise from treatment of these ores. On the other hand there exists a possibility of more efficient mining methods in some of this ore thus allowing more economic recovery.INTRODUCTION This paper has been prepared to serve two purposes:i) To propose a method of recoverying gold from a sizeable orebody at the McIntyre mine at Schumacher.ii) To summarize and present the many methods suggested to solve a very old but very real mineral dressing problem familiar to the industry as long as cyanidation itself."

Jan 1, 1971