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By Wojciech Kasprzak, Guoxian Liang, Michel Gauthier, Mickael Dolle, Yulong Liu, Xueliang Sun, Hernando Villazon Amaris, Majid Talebi-Esfandarani, Pierre Sauriol, Thomas Bibienne, Gregory S. Patience, Delin Li, Steeve Rousselot

In the 1990s, LiFePO4 (LFP) was discovered as a cathode material for lithium ion batteries and was successfully used in the variety of devices such as power tools, E-bikes and grid accumulators. New challenges associated with use of lithium ion batteries for automotive applications demand higher performance and operating requirements, yet these requirements need to be achieved at affordable cost and without compromising vehicle safety. The advantages of LFP as a cathode material include thermal stability, limited environmental impact and potential of low cost as compared to the cathode chemistries containing cobalt. Currently, solid state and hydrothermal processes are used to synthesize LFP at the industrial scale. However, they require multiple, time-consuming steps and costly precursors. Recently, a melting-casting process to produce LFP cathode material was investigated. The motivation behind this new process is the great flexibility of raw materials including chemical makeup and particle size, and the use of lower cost, commodity chemicals, with the benefits of increased kinetics in the molten state and energy efficiencies leading to overall process cost savings. Also, if successful this process could represent a novel application of conventional casting. Melting lithium-, iron- and phosphorus-bearing precursors in near stoichiometric ratios and casting LFP material that forms around 1000 °C requires fewer processing steps.

Mar 1, 2018

By L. Mabiza

Keywords: Pyrometallurgy, furnace, sulphur, SO2, off-gas, Zimplats Zimplats embarked on an off-gas sampling campaign in December 2009 to characterise the concentration of SO2 in the off-gas from their 13 MW furnace. In excess of forty isokinetic samples (US EPA Method 8) were taken over seven days. The aim of the sampling campaign was to increase the understanding of factors that influence sulphur release from sulphide concentrates in an electric furnace. Specifically, detailed monitoring was conducted over various operating conditions to evaluate: ? The relationship between SO2 and feed rate (i.e. furnace power) ? The relationship between SO2 and ingress (i.e. furnace freeboard pressure) ? The impact of concentrate bed thickness on SO2 (i.e. blacktop) ? The effect of events such as tapping and converter slag return on SO2 ? The desulphurization reactions that take place in the blacktop A model was developed to predict the SO2 content in furnace off-gas for a particular set of operating conditions. In order to evaluate the impact of random, uncorrelated changes in concentrate composition, ingress and power (feed rate) on the SO2 content of the off-gas, a Monte Carlo approach was adopted whereby concentrate composition, power, and ingress were allowed to vary randomly around selected set-points. The model is primarily based on the release of ?labile? sulphur from the partial thermal dissociation of sulphide minerals with an over-stoichiometric sulphur content (e.g., Fe7S8 decomposition to FeS and S). The main findings of this work suggest that labile sulphur does not fully account for the measured SO2 content of the off-gas, and that limited oxidation of sulphides during melting also contributes to the SO2 content. Details of sulphide oxidation reactions in the furnace remain unclear, and it is currently not possible to provide a theoretical framework for the relationship between the extent of oxidation and variables such as temperature, gas composition, particle size, and residence time in the furnace black top. Through the use of the Monte Carlo model it was, however, possible to constrain the extent of sulphide oxidation to about 1%. This work has shown in practice what was expected in concept, that SO2 in off-gas is proportional to furnace power and ingress rate. The model that was developed consistently slightly under-predicts the quantity of SO2 generated. It also highlights that more work is required to better understand the analytical methods used to analyse for SO2 in off-gas.

Jan 1, 2011

By Larry DeGraff

With the increase of new mine development in the past several years, many coal mines have decided to self- perform the design and construction for their slope development projects. The development process of determining the proper configuration is challenging, and a major economical consideration. Greenbrier Smokeless Minerals engineering staff and consultants, along with DSI/American Commercial, developed a support configuration that was best suited for their slope. The developmental process took into consideration the length of slope, depth of slope at the high-wall transition, economics of a single or multiple entries, waterproofing, stresses on the steel supports and lagging during the backfilling operation. This paper describes the developmental concept of using a single entry, side by side configuration, using steel ?Banjo String? supports with steel plank lagging, to develop a long term permanent installation in a cut and cover application.

Jan 1, 2009

By James P. Stewart

This case history describes the engineering design and construction for the Contractor of a 35-ft-deep excavation for an 800-square-foot addition to an existing sewage pump station. The site posed unexpected geotechnical complications that included deep gravelly soil, a history of local construction difficulties, groundwater consisting of heavy salt brine, and the need to underpin the existing pump station. The project took an interesting twist when the Owner issued a change order limiting the dewatering discharge to a fraction of that required to lower the water table. This documents the interesting circumstances of this job and documents the unusual subsurface conditions in the Syracuse, NY Lakefront area.

Jan 1, 2003

The development of an onboard contaminant diagnostic monitor to continuously measure contaminant level in a mining machine was advanced to a prototype stage in this contract. Several concepts were investigated and it was found that a static spool type sensor was the most reliable and accurate. Laboratory and field tests showed that an instrument based on this concept is capable of measuring contaminant levels and/or size distribution, depending on the configuration of the sensor. Moreover, this instrument can function on emulsions or homogeneous fluids. Current laboratory equipment can operate on homogeneous fluids only.

Jan 1, 1983

Support design in jointed or blocky rock masses is often approached by the use of either 'rules of thumb', rock mass classification systems such as the Q-system (Barton, Lien and Lunde, 1974) or RMR (Bieniawski, 1973) or conventional wedge analysis. Generally, this requires that a number of key simplifying assumptions are made and the support system is designed to cater for either a mean, most likely, or worst case scenario depending on the risk tolerance. The design block size is often a major uncertainty and often a worst case block size based on excavation span is used. Thompson and Windsor (2007) state that it is inappropriate to base support designs on the excavation size as these size blocks rarely occur if discontinuity trace lengths are considered. Probabilistic keyblock methods can be used to determine the most likely design block sizes. A methodology is presented whereby JBlock software (Estherhuizen, 1996) is used to estimate potential block sizes as part of the support design process. Using information such as the spacing, orientation and length of discontinuities, it is possible to simulate blocks in the walls of an excavation (Esterhuizen and Streuders, 1998). Keyblock analysis methods (Goodman and Shi, 1985) are used to evaluate whether blocks are removable and whether the chosen support will be sufficient to ensure stability. Data from two mines is used to demonstrate how probabilistic keyblock analyses can be used in support design. Discontinuity data was used to generate 10 000 removable blocks and the design block size statistics were determined. For one mine this information was used to scale blocks in a conventional. Unwedge analysis whilst for the other mine, the point estimate method (Harr, 1987) was applied. The choice of appropriate design acceptance criteria in terms of factor of safety and probability of failure is also considered.

Nov 25, 2010

By E. Wraith, W. W. Culver, B. Wesstrom, P. J. Mackey

Electrodeposited copper of the 1860s was of unprecedented purity, although the profound significance of this achievement was not fully realised until the dawn of the electrical age a decade or so later. By the 1870s there were three somewhat large (4 to 4.5 tonnes Cu/day) electrolytic copper refineries in Germany based on J. B. Elkington’s process, first patented in the United Kingdom in 1865. More such refineries were planned throughout Europe. At the same time, copper output in the U.S.A. was starting to expand and with the spread of European electrolytic copper refining technology across the Atlantic, the door opened to major increases in North American output. The technology was first taken up in 1879 by James Douglas at the Chemical Copper Company in Phoenixville, Pennsylvania, where he was Superintendent. Douglas was assisted in this pioneering work by Edward Weston. The copper refinery at the Chemical Copper Company was small, not unlike the first plants in Europe. The present authors contend that the electrolytic copper refinery at the Chemical Copper should be regarded as the first copper refinery in the United States. The Balbach Copper Refinery in New Jersey, which commenced operations in 1883 with an initial production of about 2 tonnes Cu/day, has been erroneously considered as the “first commercial refinery”; it rightly belongs in second place. The early developments at these plants are discussed in this paper. INTRODUCTION In the mid-1800s, the main uses for copper were as sheathing on the wooden sailing ships of the day to protect from marine growth, boiler components in locomotives and steam engines, along with some construction uses. Copper ores were generally smelted, and further fire-refined for market. The recovery of gold and silver, if present in payable amounts, was a slow and relatively expensive step. This situation regarding copper would change by the 1870s with advances in the generation and use of electricity. The introduction of the dynamo led to major developments in electrorefining. First demonstrated in principle by Faraday in 1831 (Faraday, 1832), the dynamo was subsequently adapted and further developed by J.S. Woolrich for electro-metallurgical applications in 1842 (Woolrich, 1842; Napier, 1845). It provided a new source of power with the unprecedented potential to significantly change the scale of metal production by electrometallurgy. Interestingly enough, copper would be needed for the electrical age just beginning. By 1869, advances in dynamo design offered relatively reliable large machines, which enabled J. B. Elkington in the United Kingdom to use the dynamo in the radically new Pembrey copper electrorefinery — the first copper electrorefinery in the world (Wraith, 2013). Initial production at Pembrey was small — in the range of 1 to 2 tonnes/day — while gold and silver were recovered more readily by the treatment of the slimes than with methods used hitherto.

Jan 1, 2019

By Sanjiv Dhanjal

"Often mineralogy dictates the physical properties of a material rather than chemistry. This in turn affects how that material behaves in a process plant, and whether optimum conditions for refining one mineral are different to those for refining another. For example how does refining copper from chalcopyrite differ to refining copper from bornite?Minerals are naturally occurring inorganic solids that have a definite chemical composition and an ordered atomic (crystalline) structure. X-ray diffraction is a common and highly developed method to identify and quantify minerals. X-rays are fired onto a material and the mineral is identified by the angles where the diffracted X-rays are in phase.Most X-ray analyzers are laboratory based. A sample is prepared and analyzed by a detector that travels in an arc to collect the diffraction pattern. COSMA has a curved detector which picks up the complete x-ray pattern instantaneously. Therefore, material is collected and transported through the machine where is it is analyzed continuously.COSMA measures about 0.5 tons of material per day, while laboratory analyzers measure a few grams at a time. Real time data trends are produced allowing for improved process evaluation and automatic control. The COSMA on-line system has taken X-ray diffraction out of the laboratory into the field.There are a number of systems in operation in cement production. It is recognized that on-line mineral analysis has a role in many other processes. This paper presents the technology and invites further discussion should the technology be beneficial to members of the audience.INTRODUCTIONThis article describes COSMA, a system that provides direct and continuous on-line mineral analysis using X-ray diffraction in the field. While X-ray diffraction is a common technique used in mineral analysis, the time from sampling to analysis can be hours and plant operators typically do not get the data in time to control a process or respond to an upset. COSMA provides rapid measurement, analysis and feedback of data, in real time. This provides powerful information that can be used to optimize operation, thereby reducing costs and increasing quality."

Jan 1, 2009

By R. Simonson

Agenda ? Need and Introduction ? Interface Management Programs ? Outcomes of Successful Interface Management ? Key Success Factors ? Lessons Learned ? Concluding Remarks Need for Interface Management ? Complex projects ? Larger in scale ? Physically dispersed and delivered remotely ? Involved with several stakeholders ? Risks thus imposed due to: ? Iterative and dynamic nature ? Large information flow ? Document revisions and information updates ? Related sources of Risk: ? Ineffective communication ? Poor work relationships ? Person to job mismatches ? Failure to clarify expectations

Aug 1, 2013

By Thomas Varley

"The literature on flotation of oxidized ores except for patents (especially for reagents) is very sparse. The Bureau of Mines in 1936, published a circular on the subject, by Ralston and Allen. The treatment of oxides by flotation was then in its infancy, but several of the most important mining companies in the Western United States and Mexico are now operating flotation plants for treating oxidized ores. The purpose of this present circular is to review the progress made and bring the subject up to date. One of the writers of the 1916 report (Mr. Allen) has been associated with some of the most important mining companies who have put into practical operation the process of flotation of oxidized ores; among these companies are the Shhttuck Arizona Copper Co., Bisbee, Arizona (now the Shattuck Denn Co.) and the San Francisco Mines of Mexico, Ltd., San Francisco Del Oro, Chihuahua, Mexico. His experience and other sources of information have been freely drawn on in pre-paring this paper. Mr. Ralston, assistant chief metallurgist of the Bureau of Mines, contributed many valuable suggestions and criticisms.Sulphidizing Reagents for Oxidize Ores.The various reagents and methods that might possibly be used for sulphidizing were summarized by Ralston and Allen as follows:""Sulphidizing (1) by the use of hydrogen sulphide on either the dry or the wet crushed ore, (2) by the use of solutions of the various sulphides and sulpho-compounds of sodium, (3) by the use of solutions of the various sulphides and sulpho-compounds of calcium, (4) by the use of sulphur vapor, (5) by the use of a sulphureted oil, (6) with colloidal sulphur."

Jun 1, 1927

The pressure of low commodity prices forced the design process for the second lift of Northparkes E26 Mine to adopt a continuous improvement philosophy. The emphasis was to minimise capital expenditure while still maintaining the excellent low operating costs achieved on Lift 1. Although the first block cave lift at Northparkes is the most productive underground mine in the world and is held up as a benchmark for the use of technology in mining, areas for improvement were identified. Every area was critically assessed and investigated for the possible application of new techniques and technologies. Key learnings from the construction and production phases of Lift 1 were captured, documented and used as the starting point for the Lift 2 design. This paper shows how and why the design parameters initially used onLift 1 were changed to become the current E26 Lift 2 developmentproposal. The main differences between the two block caves arehighlighted. The alternative techniques and equipment that wereconsidered are also discussed. * Originally published in the Proceedings of MassMin 2000,published by The AusIMM.

Jan 1, 2001

By Vladimir N. Rudashevsky, Louis J. Cabri, Nikolay S. Rudashevsky, Thomas Oberthür

"EPD (Electric Pulse disaggregation) and HS (hydroseparation) are exceptional technologies for research, concentration, evaluation, and mineral extraction of specific minerals such as precious metals (Au, Ag, PGM), kimberlites (extraction and concentration of indicator minerals), zircons and baddeleyite (recovery of objects for geochronology), and even gemstones (method of evaluation and production of the 100% gemstone concentrate of ideal crystals) etc. EPD is used for recovery of pristine undamaged crystals of diamond, emerald, ruby, sapphire etc, including large crystals. It was tested on various hard ores and was especially successful for recovery of “soft” minerals from “hard” matrix. EPD products are very convenient for HS processing, resulting in representative concentrates of all heavy minerals including the finest particles (5-10 µm). The combined EPD and HS method enables high sensitivity (20 ppb) for evaluation of precious metal ores providing objective information about original grain size, associations, and recovery using a very small amount of sample (1-3 kg). Latest developments of EPD and HS techniques at CNT Mineral Consulting Inc. include the HS-21 hydroseparator (50 kg/hr) and the Spark-21 EPD (5 t/hr), which enables use of both techniques for prospecting and mineral processing of industrial size samples of certain ores.INTRODUCTIONThe main task for mineral processors is to find a reliable technology for testing of mining feasibility and the efficiency of mineral extraction procedures. Among various mineral processing approaches of extraction and concentration there are two alternative cost-effective methods that can be described as the most environmentally benign and complementary: electric-pulse disaggregation and hydroseparation. These techniques were tested on many different ore types and process products with great success providing a precise and comprehensive mineralogical determination of different accessory precious metal and other useful minerals constituent in rocks, ores, and tailings.This article describes several examples of EPD and HS use: native gold from the Kostomuksha deposit (Karelia, Russia), a Ag-Au deposit in South America, zircons from ancient ultramafic igneous rocks of SW Greenland, bauxites of West Australia, PGM from the Driekop dunite pipe and gemstones (ruby, sapphire, emerald and demantoid) from different deposits."

Jan 1, 2008

By M. J. McLeod, S. Watters, G. G. Lutes, S. Castonguay

"Gold-bearing mineralization at Anomaly A occurs in polydeformed Ordovician turbidites of the Kendall Mountain Formation of the St. Croix belt in southwestern New Brunswick, and is hosted by WSWtrending, shallow-dipping, brittle-ductile high-strain zones associated with the latest stage of the second of four regional deformation events. Gold-bearing syn-deformational stockwork, massive, and multiply brecciated quartz-sulfide veined zones form irregular pods and sheets up to several meters thick, which contain arsenopyrite, pyrrhotite, pyrite, stibnite, and a variety of rare minerals that are gold-bearing. Mineralized zones are enveloped by locally auriferous, weakly to intensely altered wall rock. Vein paragenesis includes: (1) early (pre- to syn-D2) quartz-chlorite veins that are largely the product of migration of quartz by pressure solution; (2) crosscutting, multiphase, vuggy quartz-sulfide veins that contain most of the gold and are interpreted to be structurally controlled; (3) late, crosscutting, nondeformed, non-gold-bearing veins containing laumontite, chlorite, muscovite, quartz, fluorite, and base metal sulfides. Carbonate-poor alteration associated with zones of gold mineralization is lithology-specific, and appears to reflect overprinting of multiple events. Major elements removed during alteration include Si, Na, Mn, and Mg. The minor and trace elements removed include Co, Li, Sc, and possibly Sr, Ni, and Zn. Minor and trace elements added include Au, Ag, As, Sb, S, and possibly F, Cu, Pb, and Zr. On the basis of proximity, time constraints, and a similar ore mineral assemblage, gold mineralization at Anomaly A is interpreted to be a distal equivalent of the intrusion-related gold mineralization at the nearby Clarence Stream Main zone deposit. La minéralisation aurifère de l’Anomalie A se trouve dans des turbidites Ordoviciennes polydéformées de la Formation de Kendall Mountain, dans la ceinture de Ste-Croix du sud-ouest du Nouveau Brunswick, où elle est contenue dans des zones de déformation fragile-ductile à faible pendage de direction OSO associées au dernier stade du second de quatre épisodes de déformation régionale. Les zones aurifères syn-déformationelles se présentent en forme massive, de stockwork, ou de veines de quartz-sulfure bréchifiées à répétition formant des lentilles irrégulières et des couches de plusieurs mètres d’épaisseur contenant de l’arsénopyrite, de la pyrrhotite, de la pyrite, de la stibine, ainsi que divers minéraux aurifères rares. Les zones minéralisées sont entourées d’une enveloppe de roches faiblement à intensément altérées, localement aurifères. La paragénèse des veines comprend : (1) des veines précoces de quartz-chlorite (pré- à syn-D2) qui sont principalement le produit de la migration du quartz par solution-pression; (2) des veines polyphasées de quartz drusique et de sulfures contenant la plus grande partie de l’or, celles-ci sont considérées comme étant sujettes à un contrôle structural; (3) des veines tardives stériles, sécantes et non déformées contenant de la laumontite, de la chlorite, de la muscovite, du quartz, de la fluorite et des sulfures de métaux usuels. Les zones de minéralisation aurifère sont associées à une faible altération en carbonate contrôlée par la lithologie et semble résulter de la superposition d’événements multiples. Les éléments majeurs perdus durant l’altération sont le Si, le Na, le Mn et le Mg. Les éléments mineurs et traces perdus durant l’altération sont le Co, le Li, le Sc et possiblement le Sr, le Ni et le Zn. Les éléments mineurs et traces enrichis comprennent l’Au, l’Ag, l’As, le Sb, le S et possiblement le F, le Cu, le Pb et le Zr. Étant donné sa proximité géographique, les contraintes temporelles et les similitudes de leurs assemblages minéraux, la minéralisation aurifère de l’Anomalie A est interprétée comme un équivalent distal de la minéralisation aurifère associée aux intrusions du gisement avoisinant de la zone principale (Main"

Jan 1, 2008

By Guy Chevalier, Jean-Guy Chartrand, Louis Barrette, Daniel Michaud, Michel Fortin

"COREM has developed, specifically for the mineral industry, a mobile laboratory using the Laser-Induced Breakdown Spectroscopy (LIBS) technique. It has been used to perform onstream analysis (OSA) of the chemical composition of slurries in both gold-ore and iron-ore processing plants. Industrial tests have been carried out respectively at La Mine Doyon (Cambior), a gold-ore processing plant near Rouyn-Noranda, Quebec, and at QCM's iron-ore pelletizing plant in Port-Cartier, Quebec. The aim was to demonstrate that the LIBS technique is capable of providing information that meets the needs for process control. C, Si, Ca, Mg, Mn and Al were the elements targeted on iron ore while Cu, Fe, Ag and Au were targeted for gold ore. The results obtained meet or exceed the requirements for process control and consequently clearly show that the LIBS technique is suitable for industrial applications.The feasibility of OSA, through in-plant validations using COREM’s LIBS mobile laboratory, has been demonstrated in four essential aspects: slurry sampling, LIBS chemical measurement, robustness for continuous operation, and functionality for industrial operators.INTRODUCTIONThere is a general need for optimization in the mineral industry. Process control is a favoured means to achieve this goal (McKee 1991). Real-time knowledge of process status is the key to effective control (Da Silva 1994). Only a few techniques, such as XRF, NMR and digital imaging, are currently amenable to chemically monitor industrial processes (Braden 2002). LIBS is an emerging technique with appealing characteristics for on-line and real-time measurement of bulk material (Lorenzen 1992, Palanco 2000). While our ultimate goal is to provide our industrial partners with performing monitoring tools, a shorter-viewed objective is to demonstrate the feasibility of developing a LIBS system for OSA. The LIBS technique has shown interesting capabilities for measuring solids, liquids, dusts and gases. Our work has focused on mineral slurries (Barrette 1999 and 2001, Turmel 1999). Special equipment is needed to perform in-plant validations. A mobile laboratory based on the LIBS technology has been assembled for this task."

Jan 1, 2004

O. S. GARRETSON, Buffalo, N. Y.: If I may judge from the half-tone illustration engraved from a photograph of this medal and accompanying Dr. Prazer's paper, I do not think the cast ing is exceptionally fine. I have often made castings of simi lar character which I think were equally good. For instance, I have taken a coin, moulded it directly in fine sand, and cast from it in Scotch (or the equally good, if not better, Ameri can Scotch ") foundry-iron a copy quite as sharp and smooth as the original. The secret is in using very fine sifted sand. In fact, I have used for this purpose the dust which had accumulated on the beams overhead in my foundry, riddling it with a very fine sieve before using it. ['NOTE BY THE SECRETARY.—After the session at which these remarks were made by him, Mr. Garretson cast at his Buffalo foundry, in the presence of a number of members of the Institute, copies of the bronze pin furnished to visiting members by the Local Committee of the Buffalo meeting. The accom panying illustration, Fig. I, has been reproduced from a photograph of such a casting, made in green sand, under the conditions of ordinary foundry-practice, and not subsequently polished in any .way. I can also certify that the photo graphic negative was not touched, to improve its clearness of definition, before the production of the " half-tone" plate from which Fig. 1 has been printed. As, in the case of the Kytchtym medal, it was the thin, ribbon-like sprue, rather than the low-relief features of the medal itself, which indicated the fluidity of the metal and the sharpness of the casting, so in this work of Mr. Garretson it is the long and slender pin which offers the strongest evidence of these qualities. It is scarcely neccssary to point out that the filling in the mould of a long and nar row opening, such as this pin presents, is the severest test that could be imposed upon the casting, and that the sharpness of the point of the pin in the casting is striking evidence of the success with which this test has been met. The Pittsburgh Testing Laboratory .has made for the American Manufacturer measurements of this casting and an analysis of the sprue. The thickness of the main casting is from 0.049 to 0.068 inch. That of the tag bearing the stamped number is 0.024 inch. The analysis, which represents the iron ordinarily employed by Mr. Garretson for thin castings, is as follows :

Jan 1, 1899

By G. X. Zeng

A calculation programme of finite element method has been developed in order to study the behavior of excavation with sheet piling in soft clay. Based on a series of isotropically consolidated-undrained tests (CIU) on Hangzhou clay a linear relationship between the normalized initial tangent modulus number, E1, and stress-path parameter, a, is found for four different stress paths, and stress-path dependent modulus equations derived. Meanwhile, several influence factors, such as embedment depth and stiffness of the wall and soil conditions, were taken into consideration in the programme. Some valuable conclusions were obtained. Finally, a case history was studied by the proposed method of calculation. The result of calculation and the field observation are in good agreement.

Jan 1, 2010

By D. Harrington

A uniform hoisting-signal code for mines hoisting from more than one level, if adopted by all mining States, would be beneficial to employees and owners alike and should largely reduce the number of hoisting accidents. Misunderstood hoisting signals cause many shaft accidents involving injuries to men, damage to equipment, and loss of production from the resultant delay. Many of the metal-mining States have adopted codes for hoisting that are effective within the borders of that State but usually entirely different from the signal code, if any, in use in an adjoining State. For many years safety engineers have recognized this lack of uniformity as a distinct hazard, but a uniform code has never been adopted by the States or by the mining industry in those States that have not incorporated signal codes in their mining laws or mining regulations.

Jan 1, 1944

About MAC ? The national organization of the Canadian mining industry ? Mining, smelting and refining of base and precious metals ? Mining of iron ore, diamonds, uranium, oil sands, coal and industrial minerals ? Many associate members ? www.mining.ca

Aug 1, 2013

By Tassos Grammatikopoulos, Gary Pearse, Massoud Aghamirian, Charlotte Forstner, Stephen Mackie

"SGS Minerals Services (Lakefield, Ontario site) has conducted a number of developmental and pilot programs that examined methods for the beneficiation, extraction and recovery of lithium from a variety of spodumene containing hard rock sources. An overview of the beneficiation programs is presented separately by Aghamirian, Mohns, Grammatikopoulos, Imeson & Pearse (2011). The focus of this discussion will be the hydrometallurgical steps involved in producing a high grade lithium carbonate (Li2CO3) sample from the spodumene concentrate. SGS has applied the standard Li2CO3 hydrometallurgical flow sheet to a number of spodumene concentrates and has determined that all of these samples respond in a similar manner to the process and produce a final product having a Li2CO3 grade of >99.5%. The standard process is sufficiently robust to accommodate the observed variability in the concentrates that have been tested. Advantage of one spodumene deposit over another will thus be gained through process optimization and innovation. Optimization at the beneficiation stage and at the hydrometallurgical stage must be considered. Some aspects of the process optimization of the hydrometallurgical flow sheet will be presented.INTRODUCTION The current activity in the exploration, development, and mining of lithium based minerals is due in large part to the key role that this metal plays in the rechargeable battery industry (U.S. Geological Survey, 2011). Lithium battery technologies are widely applied in a range of portable electronic consumer products. The expanding development and production of hybrid and fully electric vehicles has contributed to the increased interest in finding and developing new lithium sources in order to meet the expected demand from the lithium battery industry. Lithium may be sourced from continental brines (sub-surface salars), hard rock minerals (pegmatite, spodumene), hectorite clay deposits, geothermal brines and oilfield brines. Currently the majority of the lithium products are produced from Li brines. The four major lithium producing countries are Chile, Australia, China, and Argentina (U.S. Geological Survey, 2009; Roskill, 2009). These countries accounted for 97.6% of the total lithium produced in 2010."

Jan 1, 2012

By Thomas Novak, Sampurna Arya

Controlling dust generation and keeping it below permissible limits to meet federal dust standards at the working face of a roomand-pillar coal mine is a challenge for a mine operator. With the recent changes in federal dust regulations requiring lower worker exposure, maintaining compliance has become increasingly difficult. The current most effective practice of dust control at a continuous miner face in an underground mine is the use of a flooded-bed scrubber. A study carried out by the National Institute for Occupational Safety and Health (NIOSH) indicated that a flooded-bed scrubber could achieve cleaning efficiencies between 58 and 90%. But, the operation of such a system is maintenance intensive. The flooded-bed scrubber screen becomes clogged with dust particles and requires frequent cleaning to maintain performance. However, the dust control issue is not solely a mining industry problem. Other industries face similar issues. The University of Kentucky collaborated with Toyota Motor Manufacturing on the development of a novel wet scrubber, called the vortecone scrubber, for capturing oversprayed paint particles in automotive paint booths. The vortecone scrubber achieved a cleaning efficiency of 99% and required minimal maintenance. This study aims to assess the ability of this vortecone scrubber to capture respirable dust in an underground coal mine. The paper presents the results of computational fluid dynamics (CFD) modeling of this vortecone scrubber. It discusses the effects of air quantity and dust particle size on the performance of the scrubber.