Search Documents

By J. R. Emery, D. F. Coates

"FOUR PAPERS ON CEMENTED BACKFILL were given at the Annual General Meeting of The Canadian Institute of Mining and Metallurgy in 1970:Weaver, W. S., and Luka, R., ""Laboratory Studies of Cement-Stabilized Mine Tailings"".Pasieka, A. R., Beattie, H. F., and Espley, G. H., ""Cemented Hydraulic Backill within the Falconbridge Group of Companies"".McLeod, P. C., and Schwartz, A., ""Consolidated Fill at Noranda Mines Limited (Geco Division)"".Clement, W. P., and Sokoloski, R., ""Pumping Cemented Backfill"".These four papers give the impression of a development in mining technology that has been substantially completed. Somewhat over ten years ago, The Inter-national Nickel Company of Canada, Limited and Falconbridge Nickel Mines Limited started experimenting with the addition of Portland cement to mill tailings to produce improved backfill and cheaper floors for scraping. Shortly after, the Canada Cement Company Limited (now Canada Cement Lafarge Ltd.), with full support of the two mining companies, started an extensive research program to provide the technologic-al data necessary to exploit what was obviously going to be a significant development in mining technology."

Jan 1, 1970

By C K. Bell, L. S. Collett

An AFMAG survey was flown in 1968 over the Upper Nelson River area, Manitoba. The flight direction was northwest-southeast and flight spacing was 2 miles. In the Cross Lake Subprovince, AFMAG showed that an isolated peridotite outcrop was part of a dike that extended over 80 miles. Diabase dikes are not always marked by an anomaly, but isolated cross-overs, when used in conjunction with geological and magnetic data, permit their extrapolation. Anomalies coincide with areas of sulphide mineralization. In the Flin Fion Subprovince, known and unknown northeast-trending faults are detected. The Berry Creek fault was extended south through Tramping lake, then under the Paleozoic cover. Conductors were detected at, or near, the axes of major synclines within Amisk and Snow Group sediments. Granitic terranes have low conductivity and, because they are characterized by smooth AFMAG profiles, they can be delimited. AF.MAG is being recognized as a geophysical method that can aid geological mapping and interpretation. Its most important contribution to the geologist will be in regions where out-crops are sparse.

Jan 1, 1971

By F. Habashi

Lead is an ancient metal, has been produced to-date from its ores exclusively by pyrometallurgical route. The process suffers from high operating cost and excessive pollution problems. Extensive research has been going on since the beginning of the twentieth century to find a non-polluting process for its production and a solution for its complex refining scheme. It has been assumed correctly that the hydrometallurgical route should be the most promising. Pilot plants have been constructed and operated for a reasonable periods, but no process has proved to be satisfactory. As a result, a number of smelters and refineries have been shut down. The present review analyses the situation and suggests that the best route to treat lead sulfide concentrates is by leaching with fluoroboric acid, HBF4, containing ferric fluoroborate, Fe(BF4)3, and electrolyzing the solution in a diaphragm cell - - a process recently invented by Italian metallurgists. In this process, any silver present in the concentrate remains in the residue together with elemental sulfur and can be recovered by known methods.

Jan 1, 2008

By M. F. Goudge

BRUCITE associated with highly metamorphosed Precambrian limestone was discovered in the vicinity of Rutherglen in northern Ontario by the writer during field work on the limestones of that district in 1937, and later was identified in similar limestone at Bryson and Wakefield, Quebec. The brucite occurs as granules disseminated through the limestone (Figure 1) and comprises from 20 to 35 per cent of the rock. Such rocks may be referred to as predazzites or pencatites, depending on the proportions of the constituent minerals. In this paper, however, the general term brucitic limestone is used to designate limestone containing brucite. In none of the deposits does the magnesia content of the rock approach that of magnesite, and in the deposits near Bryson and Wakefield the magnesia content is only that of dolomite. Therefore, without some method of concentrating the brucite, the deposits would be of little or no more value as a source of magnesia than is ordinary pure dolomite, which is abundant in many parts of Canada. Investigations in the laboratories of the Bureau of Mines have, however, resulted in the development of a method whereby, from certain of the deposits, pure calcined brucite, or magnesia, in granular form can be obtained, apparently at a cost that will enable it to compete in eastern Canada with imported magnesia. The granular magnesia so obtained appears to be highly suitable for use in basic refractories, for making magnesium metal, and for various other purposes for which magnesia is commonly used. Prospecting in the neighbourhoods of the original discoveries has resulted in a number of other deposits being found in each of the three areas, and there is now apparently available s1.dficient brucitic limestone of a grade that will lend itself to commercial exploitation to supply for many years a large part of the present and prospective Canadian market for magnesia and its products. Furthermore, it is expected that additional deposits will be discovered as prospectors and others become more familiar with the appearance of brucitic limestone.

Jan 1, 1940

By Rita Awwad

Building Information Modeling (BIM) has been gaining a significant edge in the construction industry over the last decade. BIM allows gathering all building information in one shared database that can help all construction entities better understand, integrate and visualize all work progress from inception to operation of the building. The main purpose behind BIM is to bring all project participants together (Client, Architect, Contractor, Consultant) since the initial stages of a project allowing them to cooperate and work as a team in the promise of an increased productivity, reduced cost, enhanced quality and faster delivery. However, a full-fledged implementation of BIM tools and benefits is not yet achieved in the construction industry and remains a debatable issue for researchers and practitioners in the construction field. This paper aims at assessing BIM awareness and usage in the Lebanese construction industry through conducting interviews with contractors, architects and consultants that are key players in the Lebanese market. A comprehensive literature review about BIM adoption in some developed countries and in the surrounding region is also provided in order to better evaluate the Lebanese industry status in comparison with foreign industries. This research sheds the light on BIM awareness of the different construction parties in the Lebanese market, assesses the extent of its current use, identifies the pertaining implementation challenges, and provides recommendations to enhance BIM role in the Lebanese construction industry.

Aug 1, 2013

By Michael R. Brown

A facilities success or failure of doing well during a regulatory inspection is typically measured by the number and type of citations that result, and financial liability resulting from those citations. The success of a facility during an inspection depends on several factors including, the preparation prior to an inspection, behavior and activities during and inspection, and finally, action taken following the inspection. This paper contains suggestions for improving inspection results and establishing an attitude of compliance at manufacturing and mining facilities.

May 1, 2002

By A. H. Mumin, A. Prikhodko

"This paper provides an understanding of interpreting and evaluating airborne time domain electromagnetic (TEM) surveys as applied to massive sulfide exploration. Variations in the conductive morphologies of massive sulfide ore systems are discussed, followed by forward modelling exercises examining the derived TEM response to these morphologies and discussion of the subtleties of data interpretation. Deposit morphology in the orientation at formation and the variations occurring due to later deformation are considered. Images of corresponding resistivity–depth models are provided. The combined modelling results provide a low-cost method for initial interpretation and screening of TEM anomalies. RÉSUMÉ Cet article nous permet de mieux comprendre l’interprétation et l’évaluation des levés élec-tromagnétiques aéroportés en domaine temporel (TDEM, de l’anglais time-domain electromagnetic) appliqués à l’exploration du sulfure massif. Y sont débattues les variations au niveau des morphologies conductrices des systèmes de minéralisation du sulfure massif, suivies d’exercices de modélisation prospective qui examinent la réponse dérivée des TDEM à ces morphologies et d’une discussion sur les subtilités de l’interprétation des données. L’étude envisage la morphologie de l’orientation originelle non déformée des gisements ainsi que les variations résultant d’une déformation ultérieure. Des images des modèles correspondants de résistivité-profondeur sont fournies. Les résultats combinés relatifs à la modélisation proposent une méthode peu onéreuse d’interprétation et de contrôle initiaux des anomalies dans les TDEM.INTRODUCTION Electromagnetic geophysical surveys are an indispensable foundation of many mineral exploration programs and can account for as much as half of the predrilling exploration costs. Quantitative mass interpretation of the survey results remains difficult due to the infinite variation of deposit morphologies, their complex physical properties, and the presence of barren conductive materials that can mimic or mask the response of targeted ore. Many modern geophysical investigations that focus on time domain electromagnetic (TEM) data interpretations are devoted to problems with inversion and modelling and their algorithms. Although a few of these investigations have resulted in commercial software products, these require highly qualified and experienced users and usually include geometric assumptions. Furthermore, without the input of known physical properties and geometric constraints, the inversion results are highly ambiguous. A number of case studies document the geophysical responses to known targets in well-defined and diverse geo-electrical environments, providing a high degree of correlation between field obser-vation and the results of the modelling used in this style of investigation (Hone, 1980; Schneider & Emerson, 1980; Tyne, Idnurm, & Malone, 1981; Bishop & Lewis, 1992; Hopgood & Hungerford, 1994; Meju, 2002; Yang & Oldenburg, 2016). The uniqueness of the target/environment parameters and their specific features limits the use logy is poorly understood. The responses are therefore that are devoid of complicating environmental factors (e.g., highly conductive overburden and hostrocks or nonuniform target conductivity) as a first approach to the interpretation process of such case studies as the main reference for interpreting TEM survey responses in areas where the underlying geomodelled from generalized and typical geological models"

Jan 1, 2018

By A. K. Mahto, B. Samanta

"A heuristic model was developed to simultaneously generate the ultimate pit and production scheduling at a mining project. The method consists of a preprocessing step to select a starter pit, the implementation of a genetic algorithm to optimize the pit and schedule of the starter pit, and a network-flow algorithm–based postprocessing operation to finalize the ultimate pit and production scheduling. Applied to an iron ore mine, the model pit and schedule produced a net present value 21% higher than the reference pit and schedule prepared by experienced field engineers.RÉSUMÉ Un modele heuristique a ete developpe pour generer simultanement l’ordonnancement de la fosse finale et de la production dans le cadre d’un projet minier. Cette methode comprend une etape de pretraitement visant a selectionner une premiere fosse, la mise en oeuvre d’un algorithme genetique pour optimiser la fosse et le calendrier d’execution de cette premiere fosse, ainsi qu’une operation de posttraitement basee sur des algorithmes de flux reseaux pour finaliser l’ordonnancement de la fosse finale et de la production. En l’appliquant a une exploitation de minerai de fer, ce modele de fosse et d’ordonnancement a genere une valeur actualisee nette (VAN) superieure de 21 % a l’approche de reference pour la fosse et l’ordonnancement developpee par des ingenieurs de chantier chevronnes. INTRODUCTIONLong-term planning for an open-pit mine involves two important activities: developing the ultimate pit and determining the optimum production schedule. To accomplish this, an ore deposit is discretized into a number of smallsized elements called blocks, which are presented in a 3D block model structure. Because of economic and slope criteria, only a certain set of mining blocks can be extracted from the deposit constituting a pit. During mining, these blocks must be extracted in a specific sequence known as the production schedule."

Jan 1, 2017

By A. L. Mular

"IntroductionThe mining industry has made slow but steady progress toward the automation of mineral processing plants over the last 35 years. The stimulus to automate is associated with important economic and hidden benefits, so that today, the latest in instrumentation and technology is being employed.This chapter assesses the status of instrumentation justified economically, defines levels of control and certain fundamentals of feedback control loops, describes typical sensors employed in concentrator circuits, summarizes control strategies employed therein, and briefly highlights trends in integrated plant control.Current Status of AutomationAs early as 1948, the mining industry began to show interest in automation, probably because of its close association with the petroleum industry. By 1958, some regulatory control had been achieved in various sections of a concentrator, particularly in crushing circuits. Successes were attributed primarily to the reliability of sensors employed in the corresponding control scheme. By 1961, computers had appeared on the scene, initially, for data logging purposes.From 1958 to 1965, very few new control strategies had been implemented. Guidelines in vogue at this time appeared to be:- Install proven automation, unless a good instrumentation department exists at the concentrator.- Do not bite off too much instrumentation at one time.- Do not purchase on price alone; instrumentation must function in the concentrator environment.- Do not purchase automatic control equipment to be fashionable.Such guidelines were employed1 because of a lack of: (a) quantitative process knowledge, (b) reliable primary sensors, (c) initiative to try something new, (d) trained personnel, and (e) understanding that older concentrators could justify automation in many situations."

Jan 1, 1989

By Youjun Tao

Falcon centrifugal gravity separation tests were conducted to study desulfurization and de-ashing performance with different size fractions of a high-sulfur Chinese -0.5mm fine coal in a dense medium. Performance indicators such as combustible recovery, ash and sulfur rejection, and desulfurization efficiency were used to evaluate the separation efficiency. The results show that for -0.5 mm coal particles, all performance indicators except ash rejection are higher for the Falcon concentrator than for flotation. More specifically, for the +0.125 mm size fraction, Falcon centrifugal separation produced better ash and sulfur rejection performance than froth flotation. However, the Falcon concentrator also showed higher combustible recovery but lower ash and sulfur rejection than froth flotation for the -0.125 mm size fraction.

Aug 1, 2013

By A. A. McDonald

Anode casting has been in operation for two years in Hudson Bay Mining and Smelting's Flin Flon smelter. The new plant allows all casting to be done on one shift and so achieves considerable labour savings. The equipment and operations are described. Some important features are as follows: very consistent anode weights by the use of the load-cell controlled casting ladle; excellent mould life ; very low reject rate; and trouble-free take -off tower. Some of the start-up problems are described and an outline is given of the main operator functions. Data on labour, propane and maintenance costs are presented.

Jan 1, 1977

By K. C. Corin, Z. G. Song, J. G. Wiese

In the present study the effect of using different grinding media, viz, ceramic balls, forged steel balls, 15% Cr steel balls, stainless steel and mixture of stainless steel and 15% Cr steel balls (50:50) on the flotation performance of a Platinum Group Mineral (PGM) UG2 ore was investigated. Test work was conducted using a laboratory scale horizontal tumbling mill and a batch flotation cell. Power draw to achieve a specific P80 was determined for each media type. Changes in flotation behaviour were evaluated in terms of particle size distribution, water recovery, solid recovery and valuable mineral recovery. pH, Eh and DO levels were also measured. Grinding products of five different media produced similar solids and water recovery, which is indicative of the froth characteristics, but the grades and recoveries of PGE and chromite were different. The product obtained when using ceramic media showed the best flotation performance, producing the highest PGE recovery and the lowest Cr2O3 recovery. The products obtained when using stainless steel balls (SS) produced the lowest PGE recovery and highest Cr2O3 grade and recovery. The paper proposes possible reasons to explain these observations which may have significant importance for the operation of a PGM concentrator.

Jan 1, 2015

Project Details ? Located 420 km northeast of Yellowknife, Northwest Territories ? Jericho kimberlite discovered in 1995 ? Feasibility study showed +3,000,000 carats recovered from 2.6 million tonne reserve ? Nine year mine life ? Approx. 100 person workforce in full production ? First mine for Tahera, First new mine for Nunavut Completed Ambitious Construction Schedule During 2005 o Feb ? Mar/05 Winter road mobilization o Mar ? Dec/05 Pre-stripping, earthworks o Mar ? Apr/05 Camp facility, occupied May 3 o May ? Dec/05 Process plant o Jun ? Dec/05 Maint. shop, fuel storage, power plant o Jan ? Mar/06 Commissioning, start-up o April 2006* COMMERCIAL PRODUCTION

May 1, 2006

By Dalton Fowler

"Pressure vessels used in pressure leaching and pressure oxidation processes in the mining industry are often lined with acid resistant brick and membrane systems. Although the options available when it comes to selecting materials and linings designs for these vessels appear somewhat limited there are, nevertheless? several choices which must be made in order to successfully design, manufacture and construct these linings. These choices require careful evaluation of materials properties which include, among others, thermal conductivity, thermal expansion, chemical swell, and modulus of elasticity, as well as a variety of construction methods.Some of the options available, and some of the means of evaluating them objective of this discussion."

Jan 1, 1999

By G. S. Hume

Research thrives on ideas, and the theoretical considerations of today are either the discarded notions or the proven facts of tomorrow. The progress made in the past fifty years in the acquisition of knowledge of petroleum geology is no less astounding than is the tremendous increase in the production of oil on the North American continent from 61 million barrels in 1897 to 1,917 million barrels in 1947, an increase of 3,300 per cent, with production of natural gas expanding from less than 400,000 Mcf in 1897 to approximately 4,500,000,000 Mcf, or an increase of 11,000 fold in the same period. In the search for and discovery of the oil and gas fields that have yielded such prolific wealth, no idea has had a more profound effect than has the ?anticlinal? theory of oil accumulation, propounded in 1844 by Sir William Logan, the founder of the Geological Survey of Canada, after noting the position of oil seepages on the crests of anticlines in Gaspe peninsula. Sir William apparently was not much impressed with his own idea at this time, but after the Drake well discovery in 1859 and the publication by Henry D. Rogers, of Glasgow University, formerly of the Pennsylvania Geological Survey, of a paper in which he pointed out that the seepages in Pennsylvania were on anticlines, T. Sterry Hunt, an associate of Sir William Logan on the Geological Survey of Canada, published a reasonably comprehensive statement of the anticlina theory in the Montreal Gazette on March 1st, 1861. Hunt recognized the fact that the oil ?being lighter than the water which everywhere penetrates the rocks below the water level, naturally rises and accumulates along the crown of these anticlines". This was a recognition of the fact that gas, oil, and water in an anticlinal structure separate according to buoyancy or specific gravity. For some years the anticlinal theory does not seem to have attracted much attention, but when I. C. White in 1883 revived it and put it to practical use by prospecting for 'anticlinal' oil an gas structures in Pennsylvania, West Virginia, and Kentucky, its real value not as a theory but as a fact became widely recognized. Even today, the search for anticlines as oil and gas structures is being vigorously continued. In the past fifty years, however, it has become widely recognized that petroleum and natural gas collect in many different types of structures, and these have become known by the general name of 'traps'. About 1890, terrace structures were highly regarded because it was thought certain oil fields in Pennsylvania, New York, and Ohio were directly related to them. However, as Wilson (2, p. 437) has pointed out, it is recognized to day that ?'wherever the surface evidence is complete and dependable, other factors (than the terrace structure) are found to be in control'.

Jan 1, 1948

By Thomas H. Heine

"The Rabbit Lake uranium deposit is located at 58° 11’00”N.. 103°42'36""W., close to the west side of Wollaston Lake, and approximately 800 km north of Saskatoon. The orebody is hosted by Aphebian Wollaston Group rocks, initially deposited as a series of shallow-water marine sediments consisting, in part, of carbonates and possible saliferous petites. Metamorphism during the Hudsonian Orogeny, peaking at about 1850 Ma, recrystallized the sediments to upper amphibolite grade paragneisses. This was accompanied by partial anatexis. The waning stages of Hudsonian orogenesis appear to be marked by minor granitic intrusive activity.The post-Hudsonian period was marked by a long interval of physical and chemical erosion, resulting in the unroofing of the Wollaston metamorphic complex. The entire region underwent extensive lateritic weathering under tropical to subtropical conditions. Carbonates were especially vulnerable and, in the Rabbit Lake area, suffered extensive solutioning with accompanying formation of collapse breccias. Old zones of weakness also underwent periodic reactivation.It was during this period that uranium was leached from the surrounding meta-sediments by oxidizing meteoric waters, and transported into the karsted and fractured rocks of the Rabbit Lake doline.Athabasca Group sediments eventually covered the deposit, their diagenesis taking place at about 200 °C and 900 bars. This allowed the partial to complete recrystallization of the initial mineralization, resulting in a minimum age of 1281 ± 11 Major ""first""-generation pitchblende. Periodic fault/fracture reactivation modified the hydrologic regime within the deposit, resulting in episodic mobilization and recrystallization of pitchblende and other uraniferous species. This is clearly shown in the open pit at the present time: uranium is being mobilized and recrystallized on damp pit walls as bayleyite and liebigite due to the modification of the hydrologic system by mining activities.The uranium mineralization occurs mainly as fracture fillings, coatings, and impregnations within breccia zones and intensely altered metasediments. Lesser mineralization is intimately associated with phyllosilicates which form the matrix of a carbonate-col/apse mega-breccia. The primary ore mineral is pitchblende, consisting of five generations, and from which a large suite of secondary uraniferous minerals have formed. On a gross scale the metal content of this deposit appears to be simple, consisting almost exclusively of U, but minor Ni, As, Cu, Se, Fe and Co are also present. The eastern limit of the mineralization is defined by a vertically-dipping microgranite dyke - breccia complex, containing high-grade uranium values. The orebody is truncated to the west and at depth by the Rabbit Lake reverse fault. Minor mineralization occurs as fracture fillings in unaltered plagioclasite in the footwall of the ore body. Precipitation of uranium from solution could have taken place by a number of processes. A mobile reductant (methane, carbon dioxide, etc.) may have been generated from graphite present in some of the host rocks of the orebody. Sulphides are also a common accessory and may have aided in the formation of a reducing environment. Phyllosilicates may have acted as adsorbants for uranium, allowing for its fixation. This metal has also been incorporated into the phyllosilicates themselves."

Jan 1, 1986

By P. Nos, L. Kolbeinsen, M. W. Kennedy, A. Filzwieser, R. T. Jones, A. MacRae

Modern furnace designs often incorporate extensive use of cooled elements to achieve long campaign lives at high operating intensities. However, contact between water and high temperature fluids can result in powerful Boiling Liquid Expanding Vapour Explosions (BLEVEs). Therefore cooling such elements with water carries inherent risks when used under slag and particularly below molten metal or matte. Alternative cooling media exist that can reduce or eliminate the risk of BLEVEs. These media are analysed and discussed in the context of deeply cooled furnace elements. Important factors in selecting alternative coolants are explored including: critical heat flux, thermal limits, toxicity, flammability, unit cost, etc. Key cooling system design criteria are reviewed in the context of both traditional and alternative coolants. Results of Computational Fluid Dynamics are presented for an example tap-block cooler design using a number of selected coolants. Research needs to advance the safe use of alternative coolants are presented.

Jan 1, 2015

By Y. P. Malhotra, JE. C. Carter

"Syncrude's overburden removal requirement ranges from 20 million to 30 million bank cubic metres per year to meet tarsand demands for the production of 129,000 barrels of synthetic crude oil per day. The economic tar-sand lies beneath a variable thickness of overburden materials, composed of silts, clays, some sands of lacustrine origin, wind-deposited sand dunes, and out-wash sands and gravels.For the removal of overburden, Syncrude commissioned its own mobile equipment fleet in January 1981. This fleet consists of two Demag 241 hydraulic shovels, ten Titan 33-15B trucks and support equipment. Prior to this, all overburden removal was being carried out by contractors.This paper presents an overview of overburden removal at Syncrude, with particular reference to the performance of its own fleet.IntroductionThe Syncrude Tar Sands Plant was officially opened on September 15, 1978. After an expenditure of approximately $2.26 billion, the second and the largest commercial tarsands plant was on stream toward a permit production rate of 129,400 barrels of synthetic crude oil per day. The Syncrude Plant, a joint venture of six oil companies, the federal government and the Alberta government, is a major step forward toward the goal of Canadian energy self-sufficiency.The Mildred Lake operation of Syncrude Canada Ltd. Is located 40 km north of Fort McMurray and 480 km northeast of Edmonton in the Province o f Alberta.Synthetic crude oil leaving the plant is a blend of two-third s gas oil and one-third naphtha. The two streams combine in a pipeline and flow to Edmonton. The product takes six days to make the journey, arriving at four locations in the city Imperial's Strathcona Refinery, Gulf's Edmonton Refinery, the Interprovincial pipeline terminal and the Trans-Mountain pipeline terminal. Each Syncrude owner receives a share of oil equal; to its percentage of ownership in the project. At the present time, the oil is being utilized by Canadian refineries from Vancouver to Montreal."

Jan 1, 1983

By A Palynchuk

The development of welded pipe has paralleled the general industrial development and, in particular, that of the petroleum industry. The petroleum industry's need for high-grade, economical pipeline material to make many 'of its projects feasible has been a significant factor in the development of light-wall, high-grade welded pipe. The modern welding processes, such as high-frequency, electric resistance, flash, submerged arc, etc., have some basically different characteristics. The modern high-frequency weld mill is a complex of specialized equipment that is integrated into a production unit. Each component in the unit performs a specific function in the production process. Quality control must be built into the process on an operating basis and, to maintain the quality required for pipeline standards, must be more than a policing operation. The further development of the welded pipe industry will be determined by changing and increasing demands. The technical and economic views and requirements that will influence the development have to be resolved.

Jan 1, 1964

By G. E. Agar, W. B. Kipkie, R. A. Tenbergen

"This paper describes the successful pilot plant testing of a flowsheet, developed at INCO Ltd.'s J.Roy Gordon Research Laboratory (JRGRL), for improved separation of the constituent minerals in a bulk copper nickel concentrate.The flowsheet utilized the fact that xanthate concentration on the mineral surfaces is the most important variable affecting the high lime separation and that reduction of the xanthate concentration could be effected by an oxidative conditioning stage.When the adsorbed xanthate was reduced to a suitably low level, chalcopyrite and pyrrhotite could be floated to leave a high grade nickel concentrate as the residue. Sodium cyanide was added to the froth product to depress pyrrhotite and any remaining pentlandite. The temporary depression of chalcopyrite by the sodium cyanide was overcome by introducing a conditioning step following cyanide addition. The advantages of the flowsheet; improved copper-nickel separation, operation without heating of the pulp, production of both high grade nickel concentrate ( 29. 5% Ni, . 26% Cu) and copper concentrate ( <O. 5% Ni, 30% Cu) were all realized."

Jan 1, 1984