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By S. Caron

From the early 70?s, ?Centre de Recherche Minérale? (CRM) has conducted and co-ordinated Research and Development activities for the mineralurgical and metallurgical industries. Since 1999, CRM has continued its mandate through COREM which is a consortium of 13 members that uses the benefits and advantages of collaborative pre-competitive industry / university research. In particular, COREM?s ?In-Situ Optimization Group? is involved in the implementation of modern optimization and control tools. The POP Project was launched in order to increase and consolidate the use of modern optimization and control tools and methods for mineralurgical and metallurgical processes. To ensure a successful transfer in the industry, there are a number of essential activities that have to be undertaken. These activities have been identified by COREM?s members and are grouped into three main modules: - R&D Module: Research and Development in universities, research centres and other partners; - Technology Transfer Module: integration of new tools and methods into the POP Software, industrial applications and technical support; - Training Module: education of new engineers in universities, continuing education of plant personnel through on-site workshops and resource networking by specific information exchange tools. This paper outlines the opportunities that led to the definition of the POP Project and describes its main modules. The main features of the POP Software are presented, the first application is described and finally, future developments are discussed.

May 1, 2001

By Kazutoshi Haga, Batnasan Altansukh, Yasushi Takasaki, Mohd Yazid Bin Abdul Razak, Atsushi Shibayama

"In this study, the volatilization behaviour of arsenic (As) and antimony (Sb) from arsenicantimony bearing minerals such as tennantite (Cu12As4S13)/tetrahedrite (Cu12Sb4S13) in copper ore was investigated using a roasting process. Specifically, the thermal decomposition of tennantite and the arsenic volatilization were investigated under nitrogen and air atmosphere. The roasting experiments were performed at temperatures ranging from 500 to 1,200oC and different retention times using a laboratory electric furnace. The results indicated that over 95% volatilization was achieved at 700oC. On the other hand, when the temperature increased to 1,200oC, volatilization rate of Sb reached to 90%. Therefore, volatilization of Sb requires high temperature compared to As. It suggests that As and Sb can be separated using temperature difference. Selective removal of As is possible at 700oC, subsequently Sb can be recovered as a volatilized product by increasing the temperature to 1,200oC. Meanwhile, volatilization of Cu and Fe was not observed on these conditions. The content of As and Sb in the residues obtained from roasting at 700 and 1,200oC was less than 0.3 and 0.75 mass%, respectively. The Cu content in solid residue at 1,200oC increased to 34 mass%. The clean copper concentrate with lower amounts of arsenic and antimony was obtained from the process. INTRODUCTIONRecently, arsenic (As) and antimony (Sb) contents in copper (Cu) concentrates are increasing year by year. Arsenic and antimony are present with Cu minerals such as enargite (Cu3AsS4), tennantite (Cu12As4S13) and tetrahedrite (Cu12Sb4S13) that associate with copper sulfides [chalcopyrite (CuFeS2) and bornite (Cu5FeS4)]. They are normally concentrated by flotation and treated in copper smelters. However, treatment of copper concentrates containing high amounts of arsenic and antimony by a smelting process is difficult due to environmental implications of toxic arsenic and antimony. As demand for copper continues to grow, the need to source copper from several types of resources including those that contain high levels of As/Sb becomes necessary. Therefore, a novel processes for the treatment of As/Sb bearing Cu concentrates are required. Reviews on copper resources such as enargite, tennantite and tetrahedrite containing high amounts of arsenic and antimony are covered widely in literatures by many researchers (Padilla et al., 1998; Welham, 2001; Vinals et al., 2003; Guo & Yen, 2005; Balaž & Achimovicova, 2006a; Filippou et al., 2007; Mihajlovic et al., 2007; Lattanzi et al., 2008)."

Jan 1, 2016

By M. Ataka

Magnesium alloys are not easy to plastically deform at room temperature and may suffer from edge cracking at high reductions, especially during sheet rolling. In this study, the authors attempted to improve the rollability by the low-temperature hot rolling method, in which the rolling temperature range is lower than that of hot rolling, and also by the edge-heating method, which locally heats sheet edges.

Jan 1, 2006

Drilling is a common process in mining and petroleum engineering applications which have different objectives. For example, drilling deep boreholes in tight gas formations and gas shales is becoming more popular in the oil and gas industry. By contrast, drilling deep small sized holes for mineral exploration in hard rocks is performed to obtain samples for grade analysis purposes. In both applications optimising the drilling process includes using the most effective operating parameters such as rotation speed and weight-on-bit in order to maximise the rate of penetration. Obtaining the optimum drilling parameters requires sensitivity analysis over a range of data, which would be costly and time consuming during real field operations. Therefore, conducting several experimental simulations in the lab would be very beneficial before field operations begin. A drilling rig was designed and developed to simulate various drilling scenarios. The rig works in conjunction with an existing true triaxial stress cell (TTSC) which is in use for different petroleum related applications. The rig allows drilling into a cubic rock sample of up to 300 mm size. Three independent stresses can be applied to the sample to simulate real in-situ field stress conditions while the sample may be saturated with fluid. A significant feature of the rig is its ultra-high speed rotation which can rotate up to 8000 rpm: this is to simulate hard rock drilling for mineral exploration applications where large weight-onbit could damage the bit cutters. With the proposed design, a drilling fluid of any type can be circulated in the simulated borehole similar to the real situation, to study its effect on drilling performance. The TTSC drilling lid is equipped with torque and drag measurement systems which are two important drilling parameters to be recorded during drilling operation. It is believed that this new drilling rig will open opportunities for performing major new applied research in the area of more efficient drilling in both oil and gas bearing formations and mineral exploration applications.

Aug 1, 2013

By Rick J. Chalaturnyk

In Alberta, oil sands bitumen is utilized for synthetic crude oil production by surface mining, bitumen extraction followed by primary (coking) and secondary (catalytic hydrotreating) upgrading processes, or by catalytic hydrocracking and hydrotreating replacing the primary and secondary upgrading processes. Oil sands tailings, composed of water, sands, silt, clay and residual bitumen, is produced as a byproduct of the bitumen extraction process. Several processes have been proposed for the treatment of oil sands tailings, resulting in different recovered water characteristics, consolidation rates and consolidated solid characteristics, which may have effects on the performance of the overall plant operations. A process for the same purpose has been developed by treating the oil sands tailings with CaO lime and CO2 and thickening it using a suitable thickener. In this process a release water of acceptable properties is recovered in a short retention time, which makes it possible to recycle the recovered water, probably after a reconditioning treatment, as warm as possible to improve the thermal efficiency of the extraction process. The paper presents the theory and laboratory results for the CaO and CO2 thickening of low temperature flotation tailings. The water release rates, segregation potential of the thickened underflow and chemistry of the release water are shown and discussed. It is suggested that in using the proposed process, the thickened tailings underflow can be disposed for further consolidation, or combined with the coarse tailings to produce Blended Composite Tailings, corresponding to the Composite Tailings process in the existing hot water extraction plants.

May 1, 2002

By A. Ghirian

Once cemented paste backfill (CPB) is transferred and placed into a mine stope, various coupled mechanisms will take place in the CPB material or structure. It will be subjected to strong coupled thermal (T), hydraulic (H), mechanical (M), and chemical (C) processes. Field studies have shown that the in-situ properties and performance of CPB differ from those obtained in the laboratory. This is mainly due to effects of the aforementioned coupled THMC mechanisms or processes. For a reliable and cost-effective design of a CPB structure and barricade, it is crucial to have a proper understanding of the THMC behaviour and evolution of CPB. Also, it is important to consider the effect of coupled THMC factors (e.g., self-weight pressure, drained/undrained and thermal conditions, pore pressure) while curing the CPB specimens. For this purpose, a laboratory setup is developed to investigate the properties of CPB materials. The setup is capable of curing CPB specimens (10 cm in diameter and 20 cm in height) under controlled vertical pressure (curing under stress) and various coupled THMC conditions, while continuously monitoring the evolution of total stress, pore pressure, suction, temperature, water drainage, chemical composition of the pore water and vertical deformation. Once the required curing time is achieved, the specimen can be extracted and then subjected to experimental tests of interest, such as those that determine the Unconfined Compressive Strength (UCS), shear strength parameters, saturated hydraulic conductivity and thermal properties. In this paper, we describe the developed experimental setup and present some results of the THMC behaviour of CPB under various curing stresses and rates of backfilling. The obtained results show that the THMC properties of CPB are strongly coupled due to several mechanisms, such as self-weight pressure, heat of hydration and suction development as a result of self-desiccation. The findings can assist researchers and practitioners to better understand THMC behaviour and thus design more cost-effective CPB structures.

Aug 1, 2013

By B. J. McKay, K. Schneider, H. B. Nadendla

"A series of experiments were conducted to assess the impact of zinc additions on the morphology and soundness of the interface of Al-Mg compound castings. It was found that high amounts of zinc (>15wt%) are necessary to affect the morphology and microstructure of the interface. At these zinc concentration levels, the formation of the zinc-rich phases t1 and ? were observed along with the Al-Mg intermetallic phases ß and ?. The micro hardness of all phases across the interface was found to be similar, ~200 Hv. This even hardness gradient is thought to avoid mechanical failure in the interface under load. In samples containing large concentrations of zinc (>15wt%), the formation of bubble shaped voids as well as the complete transformation of the aluminium alloy was observed. While the exact mechanism causing the voids has not been identified it thought to be connected to the Kirkendall effect. INTRODUCTION Conventional single material components are increasingly failing to meet the demands, in terms of cost and performance, of the transport industry. Compound castings have been identified as a promising alternative as they possess a number of benefits (Bührig-Polaczek, Röth, Baumeister, Nowack, & Sussmann, 2006). Compound casting is described as a process in which a metallic melt is cast around a solid metal shape. Preliminary research has concluded that for the stability of such a resultant hybrid structure it is imperative that both metals form a sound connection via form closure, force closure, or material bonding. A continuous material bond between the two metals is also highly desirable as the formation of a crevice between the metals could lead to galvanic corrosion, particular in a humid environment (Lao, 2013; Rübner, Günzl, Körner, & Singer, 2011). Even though Al-Mg compound castings could offer the biggest potential in terms of weight savings to date only a limited amount of research concerning such structures exists."

Jan 1, 2018

By X. T. Zeng, X. Z. Ding, W. R. Chen, L. R. Zhao

The effect of deposition defects in metal nitride coatings on erosion behavior is presented. AlCrN, AlTiSiN, TiSiN and TiSiN:MoS2 coatings were fabricated by reactive cathodic arc evaporation and unbalanced magnetron sputtering processes. The microstructure and mechanical properties of the coatings were characterized by X-ray diffraction, scanning electron microscopy and nanoindentation, and the erosion property was assessed by solid particle impingement testing. The erosion characteristics on the coating surface and cross section were analyzed and correlated to the defects, which played an important role by promoting formation of erosion pits.

Jan 1, 2006

By B. Chareyre, H. Pourpak, L. Scholtès, E. Papachristos

"Numerical methods used to study hydraulic fracturing in low permeability rock masses need to take into account the interaction between the progressive failure mechanism of the intact rock matrix and the pre-existing natural fractures. A fully coupled hydro-mechanical 3D discrete elements model dealing with such interaction is presented here. The ultimate objective is to grasp the role of the rock-matrix failure on the propagation of the main fluid driven fracture under different stress fields and pre-existing fracture orientations. The proposed method provides the spatiotemporal distribution of the induced crack events which can be tracked during the simulations, making possible the identification of the local mechanisms leading to macro-failure in the rock matrix or reactivation of the discontinuity planes. Fluid flow inside a fracture, pressurized crack and hydro-fracking experimental tests were simulated as part of the validation process of the model and, are presented in this paper.INTRODUCTIONWith the expansion of shale gas and geothermal reservoirs exploitation, the technique of Hydraulic Fracturing (HF) has been widely used over the past years (McClure, 2012; Britt, 2012). Despite recent advances in micro-seismicity analysis or numerical modeling (Nagel et al., 2013), the way progressive failure of rocks affects the fluid flow depending on the in situ stress conditions or the rock heterogeneities is not fully controlled yet (Zoback, 2010).In this work we focused on setting up a three-dimensional discrete elements model to study fluid driven fractures propagation. The intact rock is modeled by a discrete element method (DEM) able to reproduce fracture initiation and propagation (Scholtès and Donzé, 2013, Garcia et al., 2013). The pre-existing fractures are explicitly modeled and can be individually defined or be part of a discrete fracture network (DFN) (Harthong et al., 2012). Their mechanical response is fully coupled with the fluid within a HM-DEM framework. The fluid flow and it’s interaction with the intact matrix and the pre-existing discontinuities is modeled through a Pore-scale Finite Volume (PFV) scheme specially enhanced for fractured rock modeling (Chareyre et al., 2012, Catalano et al., 2014) ."

Jan 1, 2015

By J. W. Choung, T. Fu, Z. A. Zhou

An on-line visualization technique and methodology was developed to investigate the role of fine sphalerite (< 10 um) aggregation in flotation. The images of particle aggregates under different operating conditions were recorded and analyzed. The effect of impeller design on particle aggregation was demonstrated. This difference was not mainly due to the energy input into the system, but due to the resultant hydrodynamic conditions created by the impeller and their effect on particle interactions. The recorded image showed that adding fine silica (- 5 um) did not interfere with fine sphalerite aggregation, thereby showing no effect on the sphalerite recovery. Effect of the enlarged aggregate size on increasing flotation recovery was confirmed. Although Malvern Mastersizer produced consistently lower estimates of aggregate size than those by the image analysis, both methods responded to the changes in operating conditions in the similar trend. It was shown from this study that on-line visualization technique is a powerful tool for studying fine particle aggregation and morphology in the context of diagnosis for the flotation separation.

Jan 1, 2004

By H. S. Fowler

The Consolidated Mining and Smelting Company has been in the business of mining and exploration since its incorporation in 1906. The Company has reports written as early as 1890. Consequently, its files contain a very large number of reports, and also of maps, of ail descriptions. REPORTS Before describing the filing of maps, a brie{ note on our general system of filing reports will perhaps clarify the discussion. Reports of a non-periodic nature, primarily those based upon examinations by field engineers, are separated from all other data and filed in what we know as the Mine Series System. Each property on which reports are written is given a serial number, known as the Mine Series Number. This serial number is assigned at the time the first report is filed and it remains permanently identified with the property, regardless of its state of activity. Our mine series numbers now total over 5,000. The serial number for a property may be found by referring to an alphabetical index of properties. MAPS We found it necessary to divide maps into two groups: (1) Maps of properties (2) Maps of areas

Jan 1, 1944

By J. Q. Chen

The elastic-plastic behavior and the fracture mechanisms of two 2198 Al-Cu-Li thin sheets are investigated. The first material (2 mm thick) is in a recrystallized state after cold rolling. The second material (6 mm thick) is hot rolled and has a fibrous grain structure. The two materials are studied in both T351 and T851 conditions. Tensile tests are carried out along different sheet directions using flat and notched specimens. Fracture resistance was characterized using Kahn tear specimens and M(T) panels. Macroscopic fracture surface of smooth tensile specimens depends not only on testing material but also on the loading direction. For Kahn tear specimens, fracture is initiated in a small flat triangle whereas slant fracture is observed during crack propagation. Fracture mechanisms were investigated using scanning electron microscopy (SEM) and X-ray 3D tomography.

Jan 1, 2011

By S. A. Willis

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

Jan 1, 1948

By Andrew Dobson

The assessment and control of environmental noise from mines has become increasingly important in recent years, due to urbanization and population growth, increased regulation of environmental factors, and overall awareness and sensitivities to noise exposure.&nbsp;Minimizing adverse effects on communities and achieving compliance with local ordinances is now commonplace, and consideration of noise during the design and/or operation of a mine cannot be ignored. Ventilation equipment can represent the loudest and most bothersome equpiment at mines, however there are complexities when attempting to control the assocaited noise, due to the acoustical nature of&nbsp;mine vent fans. In fact, the utilization of traditional and/or&nbsp;industry standard methods can intensify&nbsp;the noise impact, or simply not work as intended. This paper provides recommendations on specific noise control methods that are suitable for mine ventilation equipment, based on recent assessment work and field experience.

Oct 1, 2024

By Glenville A. Collins

IN 1932, Horace Onyett at Oroville, California, built a practical floating washing plant along the general lines as now known, using a 24 in. by 12 ft. trammel; it was fed with a ½ yard dragline bucket, rated then at 200 yards per day. Onyett dubbed his plant a &apos;Doodlebug&apos; which name has clung to this type of operation ever since. In general, the &apos;Doodlebug&apos; dredge is the outgrowth of the depression of 1929, wherein many dirt contractors had surplus idle equipment and a few of them ventured to use it for placer mining. Many such plants were impractical and poorly designed and adapted often to locations not suited to the purpose. However out of the general idea came refinements until today dragline dredging has a very definite place in the gold production of the world. Many of the early operators, being mainly contractors without mining experience or technical knowledge of gold saving, geology, or mechanical design, naturally went through stages of trial and error until a workable unit became standard practice. Credit should be given Bodenson Iron Works of San Francisco, who did a notable job of pioneering and building of floating washing plants; also, to Lord and Bishop, contractors of Sacramento, who were among the early operators, and to several others who built and rebuilt their plants until the weak spots were strengthened to take the beating required, and yet deliver a high degree of efficiency.

Jan 1, 1945

By R. Erpelding

High Pressure Grinding Rolls (HPGR) are said to be a good option in new grinding circuits. Due to their low energy consumption compared to other grinding systems such as SAG milling, there is a strong incentive to check their behaviour for certain ore types. With rising energy prices the operation will become even more beneficial in future. As published in the past, the HPGR is claimed to increase the liberation of the valuable mineral component within an ore. An investigation at the research centre of Polysius was conducted to substantiate the liberation behaviour in finish grinding operations. A pilot scale HPGR test unit (POLYCOM MAGRO) with a roll diameter of 950 mm and processing capacity of 80 t/h was used. Grinding tests were completed with a screen and a two stage drying air separation process (SEPOL). Analysis included standard screen analysis, fractional XRF and modern MLA technology. A technique was developed to oppose the amount of produced slimes (resuming bad flotation) against the positive effect of producing high mass fraction at flotation-easy sizes. The paper shows how effective the use of a dry grinding separation could be in terms of production of mass of liberated metal.

Jan 1, 2012

By F. E. Lee

The following outline gives a brief account of some of the ways in which microscopy is applied to the problems arising from the various operations of the Tadanac reduction works, at Trail, B. C. The Sullivan ore is a very fine-grained mixture of galena, marmatite, pyrite and pyrrhotite. The separation of minerals associated so intimately is a difficult task and requires careful control. Various oils and reagents are used in the process as developed, and it is essential that the operators have a means of control which shall be rapid, and at the same time, approximately correct. This result is obtained by microscopic analysis in the following manner: The operator places a quantity of the material upon a slide, a drop of water is added, and it is covered with a cover glass. Upon examination with transmitted light, the zinc mineral particles appear reddish, the ordinary gangue colorless, the lead and iron sulphides opaque. This method has proved of great assistance both in the development and in the operation of the present method for concentrating Sullivan ore. The miscroscope has thus become as much a part of the metallurgical equipment as the balance and burette. The microscope used in the laboratory is a Fuess "petrographic" with a specially-made vertical "illuminator" by Bausch & Lomb, with the usual accessories.

Jan 1, 1924

By S. Uddin

Microsegregation manifests its effect on microstructural evolution of cast or welded alloys which in turn influences their important mechanical and electro-chemical properties. In the above context, mathematical models of microsegregation have proven to play an important role in estimating the nature and predicting the effects of this phenomenon in wide varieties of solidification processes. Microsegregation models are useful in designing new commercial alloys, in estimating the homogenization time for the post-process heat treatments and in many other practical applications. In this study, two semi-analytical models of microsegregation were developed to predict the concentration field of solute in the liquid and solid regions for dendritic solidification of binary metallic alloys. Both models assume that the growing dendrites are cylindrical in shape. This assumption is more realistic compared to the common assumptions of plate like dendrites that most of the earlier researchers employed in their microsegregation modeling study. The solute redistribution profile, in the developing solid layer, necessary to determine the back diffusion parameter was derived from Fick&apos;s second law for the model without coarsening. The application of this parameter in a wide range of conditions and the use of its basic form in the model with coarsening has been verified. The concept of coordinate transformation and enhancement of back-diffusion Fourier number were used in deriving the model which took into account the coarsening of dendrites. The models are then extended to deal with rapid solidification and peritectic transformations and the results were compared with relevant experimental data for Aluminum and other alloys. A good agreement between model predictions and experimental results was found.

Jan 1, 2007

By M. H. ElMaghraby

This paper describes the development and validation of a strategy for vibration-based online detection of faults in a particular class of machinery commonly found in industry. This machinery is defined by two basic characteristics that preclude it from the application of standard online condition monitoring approaches. The first characteristic is that the machine is in a constant state of transient operation, thus making it difficult to differentiate between changes in transducer measurements that are due to variable duty and those that are due to machine malfunction or fault. The second characteristic is the fact that the machinery involves multiple sub systems that are subject to identical and simultaneous loading, operating environments and duty cycles. An example of such machinery is a system of multiple hydraulic pumps driving a common load. The monitoring strategy presented here employs an anomaly detection scheme together with methods of signal processing and feature extraction that exploit the parallel duty arrangements of this equipment. Preliminary data is collected from a pair or motor-gearbox assemblies used in a material haulage system in the mining industry. Testing and validation was performed on a mechatronic test bench with both healthy and faulted components. Experiments were carried out to investigate how various configurations of the system were able to detect different types of faults. The results indicate that this approach is effective and merits further investigation.

May 1, 2013

By Dwayne D. Tannant

This paper presents a summary of results from a questionnaire sent to surface mines in western Canada seeking information on haul road design, construction, and maintenance. There has been a marked increase in the size of the trucks used over the last decade with some mines now using trucks with a payload capacity of 360mt. Consequentially, geometrical elements of haul roads, such as width, have been enlarged to accommodate larger trucks. Most haul roads are constructed on the basis of past experience without use of formal design procedures. With the introduction of larger haul trucks, problems related to rolling resistance, deterioration, and maintenance of the haul roads have become more important. This has lead to adoption of more rigorous design methods for roads at some mines, most notably for the oil sand mines operated by Syncrude Canada Ltd. A summary of the evolution of haul road designs implemented at Syncrude Canada Ltd. is presented.

May 1, 2001