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By Mostafa Benzaazoua, Bruno Bussière, Jean Lelièvre

De nombreuses opérations mimères exploitent et traitent des minerais sulfurés pour concentrer des métaux precieux (Au, Ag ... ) OU des métaux de base (Cu, Pb, Zn ... ), laissant en fin de parcours des tonnages considérables de résidus plus ou moins générateurs de drainage minier acide (DMA) selon leur contenu en sulfures. De nos jours, Jes restrictions en matière de protection de l'environnement obligent Jes opérateurs miniers a trouver Jes solutions Jes plus efficaces pour préserver Jes sites environnants de la pollution due a l'oxydation des sulfures. Cette oxydation cause une acidification accrue du milieu et une mise en solution des metaux toxiques. L'utilisation des recouvrements multicouches est l'une des solutions Jes plus efficaces pour limiter la pollution liée au DMA mais entraine des coilts de construction qui sont souvent considérés par l'industrie miniere comme prohibitifs. Une façon de rendre cette technologie applicable, d'un point de vue économique, est de désulfurer Jes résidus à l'usine de traitement et d'utiliser la fraction inerte comme composante d'un recouvrernent multicouche. Cette opération de desulfuration peut etre réalisée par flottation non sélective des résidus dans le but d'obtenir d'une part un faible volume de concentré de sulfures qui devra être géré convenablement et d'autre part un rejet non générateur d'acide.

Jan 1, 1998

By Patrick Andrieux

Cet article décrit une nouvelle méthodologie qui quantifie les chances de succès d’un sautage confiné à grande échelle de relaxation des contraintes dans un pilier de mine souterraine, pour un massif rocheux et un régime de contraintes donnés. La méthode est basée sur un nouveau paramètre nommé « Indice de relâchement », qui considère huit paramètres géomécaniques et de forage-sautage qui contrôlent ultimement le procédé. La rétro-analyse d’études de cas bien documentées a démontré que l’approche peut indiquer de manière fiable si une situation donnée de hautes contraintes de terrain est susceptible d’être améliorée par un tir de relâchement confiné à grande échelle et si le design proposé est adéquat pour atteindre ce but.

Jan 1, 2009

By V. Evans

Mine lateral development advance rates currently average about 5 metres (16.5 ft.) per day. Granduc Tunnel hit 35.1 metres (115 ft.) on their best day, 12 km from the portal, single heading forty-three years ago. This Canadian mining record remains an excellent example of rapid drill and blast excavation with suggestions for improving current practice.

May 1, 2011

By Royston Colbourne

Objectives Of Presentation - Identify specific risks - A fresh look at risk - Provide a moment reflection on risk - Open discussion on risk A route to solution and advanced thinking.

May 1, 2010

WHAT IF? ?Mine closure and reclamation liabilities were fully funded -at all times from current mine revenues ?Unexpected & catastrophic events were insured ?Remediation costs could be capped ?Risk management was improved ?best practice and independent oversight ?Host communities?concerns were adequately addressed If this could be achieved within a cost-effective financial structure, this may be a solution to a complex issue for the mining industry

May 1, 2006

Spatial information Critical to a project since it underpins: ?Discovery of mineral resources ?Orebodydefinition and technical assessment ?Mine design and planning ?Profitability and project value Data ?Single most import asset. ?Good interpretation of quality data underpins project growth and success. TEAMWORK

May 1, 2002

By C. Sideco

"Concentrate drying at the Sullivan Concentrator goes back to 1937 when the original coal-fired dryer was put into operation. This was a second hand 8' dia. x 56' long Struthers-Wells rotary dryer that came from the phosphate plant in Warfield, B.C.In 1962, replacement of the old dryer was seriously considered. The shell and the auxiliary drive mechanism were badly worn and needed replacing. In April 1963, the new 8' dia. x 65' long fuel oil-fired Struthers-Wells dryer went in operation at an installed cost of $174,000.In 1965, it was apparent that a major rebuilding of the dust collecting system would have to be done. A study was carried out and a Ducon Dynamic Gas Scrubber was installed. The system went in operation in November 1966 and has fully met expectations.In the same year, the zinc dryer was converted from fuel oil to natural gas. The conversion has resulted in savings in fuel cost of 12 to 15%.Frame No. 1Zinc Dryer PerformanceDryer Make - Struthers-WellsDryer Size 3/4 8' dia. x 65' long Drum Drive - 100 HPSpeed of Rotation - 5 RPMFeed Rate - 50-65 TPHFeed Moisture - 10-12%Discharge Moisture - 4-6%Dryer Inlet Temperature - 1600-1800°F Dryer Outlet Temperature - 200-250°F Stack Gas Volume - 25,000-40,000 CFNDust Collecting Efficiency - 99.75-99.98% Duet Loss in Stack - 50-300 lbs./day"

Jan 1, 1972

By H. Ardehali, P. Lind

Many gold deposits also contain significant quantities of deleterious elements such as arsenic. Several biological pathways are possible for arsenic exposure; special care and caution must be used while undertaking metallurgical testwork on ores and concentrates that contain high levels of arsenic. Laboratory precautions pertaining to handling of airborne dust concentrations, necessary personal protective equipment, and effluent treatment are discussed.

Jan 1, 2014

By Robert Bégin

Reconnue pour son expertise en formation minière, la Commission scolaire de l?Or-et-des-Bois, dans le cadre du projet MRN-ACDI en Bolivie, a reçu en 1999 le mandat d?implanter un programme de formation en santé et sécurité du travail dans les mines artisanales boliviennes. À la suite d?une mission préliminaire en Bolivie et de la venue à Val-d?Or d?une délégation bolivienne, il a été convenu de l?adaptabilité du modèle québécois du programme de «formation modulaire du travailleur minier» au contexte bolivien. Là-bas, les méthodes de travail sont essentiellement artisanales et la pauvreté extrême des mineurs les pousse à prendre des risques quotidiens. Les modules de formation priorisés sont : «Introduction à la santé et à la sécurité du travail», «Principes d?écaillage» et «Matériel de sautage et explosifs». Les universités Tomas Frias de Potosí et Siglo Veinte de Llallagua sont responsables de l?élaboration et de l?implantation du programme dans deux coopératives minières de leurs secteurs. Dans une phase ultérieure, le programme sera étendu à plus large échelle. Enfin, des missions de suivi et d?encadrement sont effectuées périodiquement par les représentants de la Commission scolaire de l?Or-et-des-Bois. La formation en santé et sécurité dans le milieu de travail constitue un nouveau défi pour les universités boliviennes et une source d?espoir pour les mineurs des coopératives minières.

May 1, 2001

By Patrick Chabot

Ce document présente une méthode hybride de long trou favorisant une méthode de minage initiale par chambre-magasin et complétée par une méthode de minage long trou. Cette méthode a été adaptée suite à plusieurs facteurs tels qu?une géologie complexe, une rareté de mineur d?expérience et un haut taux de roulement de main d?oeuvre spécialisée. Cette méthode a permis d'excellents résultats par rapport à la dilution. De plus, la récupération de pilier à haute teneur par forage long trou sera expliquée. Cette méthode permet aussi de récupérer le minerai qui est resté accroché dans les chantiers chambre-magasins. Introduction : La mine Géant Dormant est une mine filonienne d?or située à environ 80km au nord de la ville d?Amos au Québec. Elle est en opération depuis 1988 et à la fin de 2007, elle a produit près de 885 000 onces d?or à partir d?environ 2 400 000 tonnes de minerai pour une teneur moyenne d?environ 11,5g /t Au. Cette mine est la propriété d?IAMGOLD Corporation depuis l?acquisition de Cambior par cette dernière au mois de novembre 2006. Elle emploie 151 employés permanents et environ 41 entrepreneurs.

Feb 1, 2008

By Ramesh Subramanian

Overview Background / History Undergraduate Programs Mining Engineering Chemical Engineering Mechanical Engineering Graduate Programs and Research Student Enrolment (2002 -) Future Plans

Oct 1, 2010

By M. R. Coffin

In recent years, improved operation of the Kidd smelter has resulted in an increase in blister production capacity. Due to manpower and equipment limitations anode production and treatment rates could not be increased without incurring significant additional operating expenses. The option chosen to expand casting and refinery capacity to meet the available blister supply was to increase the anode thickness while maintaining the same anode exchange cycle in the refinery. This has resulted in a cathode production increase of almost 10% for minimal expenditure. Equipment and process modifications required to cast and refine the thicker anodes are discussed in this paper, along with the Six Sigma methodologies used to identify them. Key areas covered are Hazelett continuous caster operation, refining process parameters, plating performance and cathode quality.

Jan 1, 2007

By A. C. Atenas

The majority of refineries that operate with traditional starting sheet technology ?starting sheet- uses a relatively low current density of 250 A/m2. Industrial tests at high current density with conventional technology were carried out in Refinery of Potrerillos, getting satisfactory results that are similar the results obtained with permanent cathode technology. The series of copper refining electrolyses electrolysis trials were carried out between 300 to 325 A/m2. Electrolysis conditions, in accordance with industrial practice, were kept constant in all sets of experiments and were as follows; 45 g/L Cu 2+, 210 g/L H2SO4, 62 °C, electrolyte circulation of 14-18 L/min. The same Dosing dosing of Additives additives used in permanent cathode technology was required in these tests. In general, only not importantminor operational modifications were necessary in comparison to normal practice in the Refinery to assure the good results. Different quality of starting sheet and anodes were examined. The test included starting sheets from smelter and laminated process. Results indicate that the charge physical quality of the electrodes and the control of the process during the two first days of operation are the keys to get the best results.

Jan 1, 2007

By D. Royston

Reducing SAG Mill feed size has been a major trend in recent years. ‘Mine to mill’ strategies have reduced blasted-rock size, and in a growing number of operations reducing the primary crusher CSS and/or adding additional crushing upstream of the SAG mill have reduced rock feed size. While reducing feed size will increase SAG mill throughput, issues arise in terms of retaining charge in the mill, exposing the shell lining to impact damage, and maintaining milling performance should the pre-crush system shut down. This paper reviews the past experience on pre-crushing for SAG mills and provides an analysis of liner design (in particular grates and shell liners) for pre-crushed feed.

Jan 1, 2012

By E. Roman E.

A novel anode slime purification process was developed and tested at pilot scale in the Chuquicamata Refinery. The process consists of three main stages: First, an atmospheric alkaline leaching at 90°C, under controlled pH and ORP operation parameters where metalloid impurities are preferentially removed from the anode slimes with high efficiency. In a second stage, alkaline washing of the mud leached with addition of reducing agent, with the intention of reducing the silver of the AgCl to metallic silver releasing the chloride, and finally, copper and other remaining impurities are leached out in mild conditions (60°C, one hour in sulphuric acid). In a side process Se, Te, and Sb are recovery with high efficiency from the alkaline liquor as chemical grade products. The global balance shows a high mass loss yielding a final product with high precious metal and low impurities content showing advantages in both a technical and economic point of view with a clear environmental sustainability. This treatment allows either the direct sale of the purified anode slimes or its pyrometallurgical treatment to obtain metal doré without emissions of Se, Sb and As. Chemical mechanisms for this novel process are also described.

Jan 1, 2007

By R. D. H. Wigmore

"The title of this paper probably sounds quite simple and self-explanatory. The problem, however, was not a simple one, and proved somewhat baffling and expensive over a period of years. After outlining the problem, and the methods which were used to overcome it, we will present our solution, or perhaps it would be more accurate to say the partial solution which we reached.We have in the cyanide circuit at Upper Canada two Dorr Single Tray Thickeners with 30 ft. diameter wood stave tanks 12 ft 4 1/ 2 in. deep. In the years prior to 1948, when the tonnage was 250 to 280 tons per day, two stage thickening was practised. As the tonnage was increased to 450, 500, and finally 560-600 the thickeners were used in parallel.Some settling problems were encountered, and in those days the means to combat these problems were very few. The only remedy was to dump in pounds and pounds of lime. Then along came a few reagents, and the writer remembers one in particular, - 11 Carboxel11 (carboxymethlycellulose). When water or solution was added to this reagent, the result was a gooey mass somewhat resembling tapioca. One drawback was that it stayed in this state, and didn't go anywhere. A method was finally developed of containing the mass (or mess) on a fine screen, and dissolving some of it was a fine spray of solution. The only thing the writer recalls was that it was not a very effective settling agent.Shortly after this time, along came the new flocculents, first a few, and then many, and our settling problems were over.But when the settling problem was solved at Upper Canada, some other problems were creeping up on us."

Jan 1, 1965

By K. Koyama

As a study to establish a new energy-saving copper recycling process, the copper deposition at a cathode and oxidation of copper(I) at an anode from ammoniacal alkaline solutions containing Cu(I) or Cu(II) were investigated in order to examine the feasibility of electrolysis in this solution.. The current efficiencies were greater than 95% in the current density range of 200 to 1000 A m-2. The current efficiency decreased with the increasing Cu(II) concentration and temperature. In the batch-type electrolysis at the anode, during the initial stage, the current efficiencies were 100%, and the anode potentials ranged from 0 to 0.15V vs. SHE at a current density of 100 A m-2. During the subsequent stage, the current efficiency decreased with time, and the anode potential was around 1.35V vs. SHE where oxygen evolution at the anode surface was observed. As a result, the present electrolytic method can be the core technology in the said copper recycling process.

Jan 1, 2007

By Mauricio Olivares

About Largest combined Phosphate and Potash company in the world Corporate headquarters in Plymouth, Minnesota Publicly traded on NYSE under MOS

Aug 1, 2013

By H. Henein

Atomization provides many advantages in processing such as rapid solidification and near net shaping. Two atomization techniques will be compared and contrasted in this presentation: Single fluid atomization techniques such as Impulse Atomization (IA) and gas atomization. The characteristics of both processing approaches will be presented. Results in powder structure, size and size distribution as well as microstructure will be discussed. A comparison of spray formed ingots carried out using both techniques will also be presented.

Jan 1, 2007

By Blandine Arseneault

The Raglan Mill had been in production for less than a year when the initial toxicity tests on the effluent revealed that it was defined as ?toxic? under regulations. Testwork was begun to address the fundamental reasons for the toxicity and a systematic approach was initiated to identify causes. Elimination of the problem presented a challenge once the main conclusion identified high dissolved solids as the principal culprit. In particular, normally benign soda ash (sodium bicarbonate) reagent additions used in milling, was identified as the main contributor to the problem. Following analysis of all requirements and safety considerations, a concept to recycle 100% of the mill process water was pursued. In addition to meeting regulatory requirements, this project would have numerous positive benefits to the operation, including reducing fresh water consumption and lowering costs.

Nov 1, 2002