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By Boris Yacksic, R. W. Bruce

"The flotation of a cassiterite ore with oleic acid will recover primary or rougher concentrates assaying over 10 per cent Sn, with a recovery of 80 to 90 per cent. These rougher concentrates cannot be up-graded to a marketable grade by normal reflotation. Experiments were conducted on low-grade tin ores, and a process was developed for up-grading the rougher flotation concentrates by a reverse flotation technique. The process was tested on a number of samples of ore from the Catavi mine in Bolivia. The results of these tests showed that a concentrate assaying 40 to 60 per cent Sn could be readily produced, with a recovery of 60 to 75 per cent of the tin in the ore."

Jan 1, 1967

Phelps Dodge has recently operated a commercial scale, super fine grinding circuit of copper concentrates for use in a medium-temperature pressure leaching process. Two 355 kW vertical stirred mills were installed in series, targeting a grind of 80% passing 7.5 µm and 98% passing 15 µm as outlined in Phelps Dodge's concentrate leaching patent portfolio. This paper details the operation and results of the test program at Bag dad, as well as some of the operating challenges encountered.

Jan 1, 2007

By Owen Matthews

Introduction For the past year and a half, the mill of Cochenour Willans Gold Mines, Limited, McKenzie Island, Ontario has been roasting arsenopyrite-gold concentrates, prior to cyanidation, by means of a roaster employing techniques that are new and novel. The roaster is known as the Dorrco 'fluo-solids reactor', and the technique as 'fluidization'. The reactor has demonstrated its ability to roast a flotation concentrate containing arsenopyrite, pyrite, stibnite, small quantities of other sulphides, and some lime silicates and carbonates, yielding a calcine consisting mainly of porous iron oxide, plus the gold values. This calcine is readily amenable to cyanidation. Bulk shipments of concentrates to a distant custom smelter, as practised prior to this installation, has thus been eliminated, with appreciable savings in smelting charges, freight costs, and interest losses during shipment and smelting. This is the pioneer installation of fluo-solids roasting at a Canadian mill and up to the present performance results have not been published. It is the purpose of this paper to present the information now available for the benefit of other millmen who may be confronted with identical or similar problems to those encountered and solved at Cochenour Willans.

Jan 1, 1949

By Tugba Cebeci, Bahjat Khoshaba, Bern Klein, Libin Tong, Andrew Bamber

"Sensor-based sorting technologies have potential to pre-concentrate low grade subeconomic ores through discarding the barren waste particles. However, the inability of sensors to accurately discriminate ore from waste is a barrier to prevent their wide applications. The present study focuses on the development of more intelligent sensing systems by using correlation and regression analysis of X-ray fluorescence (XRF) sensor responses on the copper ore samples obtained from Chile. The responses obtained through XRF scanning were reported both in the form of counts and the grades of elements. Linear and multiple linear correlation analyses were made between the XRF counts and the copper grades obtained through chemical analysis. Both the heterogeneity of the ore particles and the matrix effect in the XRF measurement are discussed in the study.INTRODUCTIONSorting can not only discard waste rocks away from the concentrator but also recover metal bearing ore particles that would be lost to the waste dump. The benefits of ore sorting include reduced energy consumption, water and reagent usage in the downstream operations (Bamber, 2008; Gunson, Klein, Veiga, & Dunbar, 2012; Kleine & Wotruba, 2010; Knapp, Neubert, Schropp, & Wotruba, 2014; Kobzev, 2014; Lessard, de Bakker, & McHugh, 2014; Mazhary & Klein, 2015; Robben, Wotruba, Robben, von Ketelhodt, & Kowalzcyk, 2013). X-ray fluorescence belongs to sensor-based sorting technologies and Xrays are a high energy-high frequency form of electromagnetic radiation inhabiting the region between the ultraviolet radiation and gamma rays (Shackley, 2011). Recent XRF sorting studies on low grade copper ores were carried out at MineSense Technologies Ltd. aimed at increasing the capacity related to improving the understanding of ore heterogeneity as the basis for developing semi-bulk or bulk sorting systems (MineSense Technologies Ltd., 2016)."

Jan 1, 2016

By Rodney A. Cooper

The Mary River iron ore deposits were discovered in the 1960?s. The high quality of the deposits was immediately evident, and drilling programs were successful in defining a resource adequate for supporting a feasibility study. Through a combination of ownership, market and political forces, the deposits were not developed. Having missed the window of opportunity, the project remained dormant for over three decades. Baffinland Iron Mines Corporation, with its 100% ownership of the Mary River deposits, began trading publicly in 2004. Modern exploration and metallurgical test work began in 2004 and has continued in 2005 and 2006, resulting in total expenditures during this period of almost C$60 million. In May 2006, an engineering team lead by Aker Kvaerner E&C, a division of Aker Kvaerner Canada Inc., completed a scoping study based on the first of five identified deposits. Highlights of that study include direct shipping of high quality lump ore to Europe over a 34 year mine life at a production rate of 10 million tonnes per annum, based on an indicated resource of 309 million tonnes at 66.1% Fe and an inferred resource of 28 million tonnes at 65.9% Fe. Capital costs were estimated at C$1.5 billion. Using iron ore prices approximately 36% below that of the 2006 market, a pre-tax internal rate of return of 15% was estimated assuming equity financing. Payback on initial capital was 5.9 years. The pre-tax life-of-mine cash flow was estimated to be C$6.3 billion. As a result of this study, Baffinland initiated a Definitive Feasibility Study, under the management of Aker Kvaerner, which is scheduled for completion in December 2007. This paper touches on the geology of the deposits, the current resource and the outlook for expansion. Project permitting, construction planning, logistical challenges and ocean shipping considerations are discussed, providing a current perspective on the project scale, scope and timeline for commercial production. In addition, an overview of the Company?s bulk sampling program will be provided.

May 1, 2007

By F. L. Thompson

MAN has been using lubricants of one type or another for at least four thousand years, and probably for a much longer period. We have learned from the inner wall of the tomb of Tehuti-Hetep, on which is a decoration illustrating the method of moving a great stone statue, that as early as 1650 B.C. lubricants were used to facilitate the movement of heavy loads. The Egyptians had available nearly every animal oil and fat, as well as at least thirteen vegetable oils, of our time, all used for food products and in the arts. Examination of the deposit on the axle of a chariot from an Egyptian tomb of 1400 B.C. showed it to consist of animal fat, quartz, sand, iron, and compounds of aluminium and lime-indicating a manufactured lime-soap grease made with lime-soap and possibly tallow. This would not be a bad lubricant for the axles of chariots which had to travel over sandy soil in hot weather. As to the method of grease application, it is remarkable that, from the time wheels were first used in the far distant past up to the present day, no one has ever thought it necessary to design a seal to keep the lubricant in and the dirt out. While time certainly marches on, we have today, in waggons throughout the world, exactly the same form of lubrication as was used in the earliest chariots. From the early days of the chariot until shortly before 1800 A.D. (when the steam engine was introduced), the main heavy equipment required for mining purposes, for machines of war, etc., was made of wood. The bearings were rough, but usually they had metal in the lower half. Light machinery was made of bronze, brass, or iron. Large clearances and poor alignment, plus the fact that speeds were much below present-day demands, combined to provide conditions that were quite satisfactorily met by the lubricants available. These were often produced locally by the machine operator. In northern countries, lard oil, prepared from the fat of hogs, was the universal lubricant employed in machine shop, as a belt and leather dressing, and for cutting operations. Sperm oils were used for light machinery, whereas beef and mutton tallow were more generally employed for the largest bearings. For the early steam cylinders, a slug of heated beef tallow was injected wherever the cylinders gruntingly complained of a lack of lubricant. Southern countries, however, resorted to the use of vegetable oils-olive, cocoanut, etc.

Jan 1, 1940

By J. B. Mawdsley

From the view point of the mining engineer, the square-set method of stoping as practised at Butte, Montana, is one ?of the outstanding features of well conducted mining operations in that camp. The following information was obtained in the course of two months underground work in the Granite Mountain mine, during the summer of 1920, which is one of the properties of the North Butte Mining Company, situated on the well known Speculator vein. Most of the information was derived from personal observation and from discussions with various miners and with members of the staff. Geology The copper mining area of the Butte district is some two miles long by one and a half miles wide, a mineralized area in a great batholith of monzonite granite, locally known as the Boulder batholith. This extensive body of granite is traversed by several series of mineralized fault-fissures which differ in strike but generally dip steeply. Geologists agree that following the formation of the fissures, alkaline solutions ascended and decomposed the felspathic portions of the granite in the immediate vicinity of the fissure walls, and that these alkaline solutions were followed by cupiferous solutions which filled the fissures and replaced the granite next to the walls. A zone of oxidized ore, varying in thickness from 10 to 400 feet, overlies a sulphide zone containing chalcocite, enargite, bornite and chalcopyrite, with a small amount of quartz gangue. The veins are from 3 to 100 feet in width and contain, on the average, 3 per cent of copper, 2 ounces of silver, and 15 cents in gold per ton.

Jan 1, 1925

By J. S. Godard

The mining developments in western Quebec have shown the ores of this district to be more complex in character than was at first expected. When the initial discoveries were made it was thought that the ores would be similar in character to those of Kirkland Lake and Porcupine areas. Developments have since shown that although the ores along the southern margin of the belt are somewhat similar, those within the belt, constituting by far the greater proportion, are vastly different, being complex mixtures of base-metal sulphides carrying values in the precious metals. These mixtures of base-metal sulphides of copper, zinc, and iron, present several problems to the metallurgist, especially in their concentration into marketable products. For the purpose .of this paper the following classification may be made of the ores of the district. Group I. - Milling Ores: (a) Ores in which~ arsenopyrite is the predominating sulphide. In this class of ore the gold occurs in fractures in the quartz and is associated to a lesser extent with the arsenopyrite and pyrite. Examples of this class of ore are the Granada, south of Pelletier lake, and the O'Brien and the Thompson in Cadillac township. (b) Ores in which iron pyrite is the predominating sulphide and gold is the valuable constituent. This may also be classed as a concentrating ore-Group III.

Jan 1, 1928

By N. A. Jabit

The dissolution behaviour of ilmenite in acid solutions has been studied by many researchers to improve the leaching efficiency. Most studies which utilized natural ilmenite from different origins resulted in different reactivity due to the alteration caused by the weathering process. Previous researchers have suggested that the greater reactivity shown by some ilmenite samples towards sulphuric acid may be a result of the mineral being relatively unaltered. In the present study a rotating synthetic ilmenite disc of 2.2 cm diameter was subjected to leaching studies in hydrochloric acid. The dissolution rates of iron and titanium from synthetic ilmenite were determined in hydrochloric acid solutions (4 M to 9 M) over a temperature range of 50 to 80°C. Results show that the rate of dissolution of both iron and titanium increased with the increase in acid concentration. However, the rates decreased with time and obeyed a parabolic rate law indicating the blockage of the surface by an insoluble product. The rates of dissolution of both iron and titanium were higher in the presence of SnCl2 and remained unaffected with time indicating the reductive role of SnCl2 which inhibits the formation of surface blocking solids. Application to natural ilmenite is also discussed.

Jan 1, 2014

By C. Butcher

Numerical simulations of straight tube hydroforming of a dual phase steel were performed using both upper and lower bound constitutive models for porous ductile materials. The Gurson model is based upon an upper bound approximation to the material behavior and thus overestimates formability. Conversely, a lower bound solution to Gurson's unit cell geometry was developed by Sun and Wang to provide a conservative estimate of formability. The effect of a compressive axial load (end-feed) on damage development and tube formability is investigated. The resulting upper and lower bound models successfully captured the experimentally determined burst pressure, formability and failure location.

Jan 1, 2010

This paper describes results of an investigation of fracture during tube expansion of 5052 and 5754 aluminum seam-welded tubes to optimize the forming of aluminum tubes during hydroforming. The tubes were produced in laboratory by press forming of tubular blanks and pilot-scale high frequency induction welding. The effect of property mismatch between the weld and base metal has been investigated. The material work-hardening was obtained by roll forming of sheet blanks in the 0-temper and H32 temper condition. The results showed that a significant work-hardening can be present in aluminum tube without causing weld fracture during tube expansion. The work-hardening increases the yield-strength mismatch between base metal and weld. Annealing reduces the hardness of base metal leading to more uniform deformation during tube expansion. As a result the occurrence of weld fracture is reduced. The study showed significant deformation of the welds during tube expansion. Weld thinning can be as large as parent-material thinning before fracture. To avoid fracture at the weld joint, good formability and high yield strength of the weld is needed. FEM simulation showed that minimizing the width of the weld joint can reduce thinning of the weld.

Jan 1, 2004

By W. A. Parks

Stone that may be applied to purposes of construction is available in nearly all the inhabited parts of Canada, the most important exception being the prairie region, but, even here, the deficiency is overcome in many parts by a wealth of glacial field-stones. In many parts of the country, also, the accessible stone is of a quality so poor that brick is more generally used. There is a great difference, however, between stone that 'may be used' and stone suitable for buildings of a monumental type or even for 'trimmings' on the better class of dwelling in the cities and towns. It is in the latter sense that the expression 'building stone' is commonly used. Thus restricted the term includes varieties of sandstone, limestone, and granite, using the latter word in the custom of the quarryman, not only for the true granite of the geologist but for many other igneous rocks as well. Building stone of high quality grades imperceptibly into stone suitable for monuments, particularly in the case of the granites. The present review will deal with building and monumental stone in this restricted sense and will omit marble, although that material has been used to some extent for building. For instance, the Great West block in Winnipeg is built of marble from British Columbia.

Jan 1, 1925

By M. Pawlik, E. Arinaitwe, V. Ferrera

A series of flocculation tests were performed on dilute quartz suspensions with the use of five polyacrylamide-based flocculants of similar molecular weights but of different degrees of anionicity. The tests were performed as a function of ionic strength and pH. The macromolecular conformation of flocculants in solution was assessed through intrinsic viscosity measurements under the same physicochemical conditions as those of the flocculation tests. It was generally found that the flocculating efficiency of the polyacrylamides correlated with their ability to coil or stretch in solution. Polyacrylamides with the degrees of anionicity on the order of 10-18% showed the highest flocculating efficiency in terms of the settling rates of the flocculated solids and the residual turbidity of the resulting supernatant. At the same time, these most effective flocculants were also found to exhibit the greatest tendency to coil and stretch in solution. This result suggests that the flocculating power of a flocculant is determined not only by its ability to adsorb onto (and bridge) fine particles but also on its ability to conform to the size of the resulting floes.

Jan 1, 2009

By W. N. B. Armstrong

CORROSION of metals, for the purpose of this talk, may be divided into two general classes, namely, atmospheric and chemical. Atmospheric corrosion is caused by the natural agents -water, air, salt, and temperature -as well as by the agents arising from industrial operations which pollute the atmosphere. Chemical corrosion affects metals in refineries and chemical plants where severe conditions exist due to .acids, alkalies, salts, solvents, gases, ?steam, etc. A special condition is encountered on road equipment and motor vehicles due to the large amounts of corrosive salts which are used on our roads in the winter. Exposure to corrosive conditions such as those referred to above causes metal to be destroyed and, therefore, it has to be protected. The non-metallic or organic coatings used to protect the metal are themselves destroyed ultimately by these same conditions. Since all types of organic coatings do not have the same kind and degree of resistance to degradation, a particular kind of -coating must be used for a particular set of conditions in order to obtain the maximum benefit. In ?addition to the above mentioned agents, organic coatings are degraded ?by sun-light, which is probably the severest single factor in the breakdown of organic coatings exposed outdoors. We can divide organic coatings, in a general way, into the following classes: (1) Conventional coatings, and (2) Special coatings.

Jan 1, 1958

By A. Lopez-Valdivieso

Particle size enlargement processes play an important role in solid/liquid separation, and in beneficiation unit operations. In the latter, not only the size of the formed aggregates but also their surface properties are very important. Oil agglomeration has a special place among such processes: it is a selective process in which hydrophobic particles are agglomerated into hydrophobic agglomerates which can be recovered by flotation. This explains the broad applications of oil-assisted beneficiation processes not only in the beneficiation of fine coal, but also in agglomerate flotation of many different types of ores, and in coal/gold agglomeration.

Jan 1, 2004

By Michael Moats, Adirek Janwong

The use of cylinder electrowinning cells, such as emew® technology, for the recovery of silver from primary and secondary sources has been growing. In this study, common operating parameters used in silver electrowinning were evaluated for recycling applications. Silver powders were produced from an industrial solution in a laboratory scale emew® cell. A design of experiments was employed to evaluate the effects of HNO3 concentration, iron concentration, current density and solution flow rate on current efficiency, particle size, bulk density, and crystallographic orientation. Current efficiency was affected by each parameter with increasing HNO3 concentration having a strong negative effect, increasing iron concentration and current density having moderate negative effects and increasing flow rate having a positive effect over the ranges examined. Finer particles were produced with increasing current density and decreasing flow rate. Bulk density increased when HNO3 concentration increased. The crystallographic orientation of all powders was dominated by the (111) plane. Increasing flow rate decreased the relative intensity of (200) direction. Based on these observations, silver electrowinning in cylindrical cells can operate at high current efficiency and produce larger powders at low HNO3 concentration, low iron concentration, low current density and high flow rate.

Jan 1, 2014

By W. A. Jones

Purpose of Paper Geophysics is a highly developed science which has found a wide use in industry. Perhaps the most spectacular application has been in the field of oil exploration. It has been estimated that, up to the end of 1939, geophysics was responsible for the discovery of five billion barrels of oil. In 1944, the sum o $40,000,000 was expended for geophysical work in the search for new oil deposits. Although the metal mining industry has so far made comparatively little use of the science, it is becoming increasingly common for the exploration engineer or geologist to be required to co-operate with the geophysicist. Many papers dealing with applied geophysics have been published but in most of them advanced training in physics and mathematics on the part of the reader has been assumed. It is difficult for the average engineer to obtain a ready understanding of the equipment, field procedure, and scope and limitations of the science from the literature. The present paper attempts to describe briefly and in simple terms the principles underlying magnetic, self-potential, and electrical resistivity methods and their application to a field problem. Introduction Geophysics is concerned with the study of gravity, magnetism, natural earth currents, earthquakes, vulcanism, and many other natural phenomena. The methods, originally devised for the measurement, for scientific purposes, of the forces associated with such phenomena have been adapted to the search for buried deposits of economic value. If the body sought has large dimensions and distinctive physical properties, geophysical measurements may reveal associated, and in some cases quite characteristic, anomalous features. However, in many instances the mass cannot be indicated directly but has a common association with geological features which can be defined by physical measurements. Although such surveys cannot specifically identify oil, metalliferous minerals, or other commercially valuable substances, it is possible to delineate anomalous sub-surface physical features which, with the help of geological information, can be assessed as possible or probable indications of the body or structure sought. The nature and extent of the material causing an anomaly, and its economic importance, can only be determined by further exploration, such as drilling.

Jan 1, 1947

By M. J. Marinigh

Increased safety requirements, higher operational costs, greater environmental restrictions, and new competitive processing techniques are the challenges smelter operators must confront in order to remain economically viable. In converting furnaces which have tuyeres such as the Noranda Reactor and the Teniente, Peirce Smith and Hoboken converters, efficient tuyere line management is critical to optimizing blowing rates, increasing refractory life, and improving safety. This paper will describe recent improvements made to equipment used for tuyere punching, tuyere silencing, tuyere pyrometry and refractory drilling of tuyeres and how the proper application of the equipment can lead to operational and safety improvements.

Jan 1, 2007

By L. M. Pidgeon

Introduction The production of magnesium by direct reduction of the oxide has far passed the experimental stage and was responsible for 30 per cent of the recent wartime production of 246,000 tons per annum. This paper describes the small-scale experiments which culminated in a number of the wartime plants. The paper traces the author's early experiments on various direct reduction reactions leading to his choice of the ferrosilicon reduction of dolomite and the realization that this reaction would proceed at a satisfactory rate at temperatures obtainable in metal apparatus. MgO has a standard heat of formation of 146,100 cal. and is therefore one of the most difficult oxides to reduce. However, if advantage is taken of the relative volatility of magnesium metal, thermally unfavourable reactions may be utilized. In reaction MgO + X = XO+ Mg . . . . . . . . . . . . . (1) the removal of Mg as a gas at high temperatures displaces the equilibrium to the right in the face of the unfavourable thermo-chemistry which is inevitable with any X other than calcium metal. If X is carbon, not only is the reaction highly endothermic, but CO is gaseous. A temperature of l,864°C. is required to produce a pressure of one atmosphere of Mg. Between l,900°C. and perhaps 400°C., the back reaction takes place readily and special shock cooling devices are required to recover magnesium from the gaseous mixture. This reaction does not lend itself to small-scale experiments and was not examined by the author. If, in reaction, carbon is replaced by a relatively pan-volatile metal, the oxide of which is also non-volatile and possesses a fairly high heat of formation, a reduction reaction is offered which is free from the difficulties associated with carbon. The typical case of silicon will serve as an example: 2MgO + Si = SiO2 + 2Mg (g) . . . . . . . . . . . . . . . . . . . . . . (2) At temperatures above l,000°C., a positive pressure of magnesium will exist over the system. Removal of the magnesium vapour will displace the reaction to the right in the face .of an unfavourable thermal balance. Since magnesium is the only volatile component at this temperature, it may be evolved and condensed, using attractively simple distillation technique.

Jan 1, 1946

By A. D. Dalvi

Economics, Resources, Environment and Technology are the major driving forces in the base metals industry. However, these factors are intertwined and together will propel the industry in the future. The demand for metals has grown with economic expansion, between 2 to 4 % p.a. The current growth cycle has been driven by economic expansion in China where the demand for base metals has risen from - 7 % of the world demand in the 90's to - 25 % of world demand today, and rising. Base metals are commodities and their demand and price are cyclical. Historically metal prices have declined in constant dollars, forcing the industry to reduce costs, increase productivity and increase the scale of operation for economies of scale. Due to resource depletion and capacity expansion the industry is driven to expand its reserve and resource base. However, in the case of sulphide deposits of copper and nickel it appears to be a losing battle. For nickel the laterites represent a vast source at this time. Their development requires development of new technologies to make these resources economic. Emission reduction is being increasingly mandated in most jurisdictions with all governments enacting progressively more stringent regulations. The industry has been responding with technological innovation. With the Kyoto protocol there is a push to reduce energy intensity in metal production. Technological innovation is driven by all the other factors and is leading to novel ways of doing exploration, mining and processing, that would maximize resource delineation and utilization, reduce costs, increase productivity, reduce energy consumption, maximize asset utilization and reduce environmental affects. Development of alternative technologies such as Pressure Acid Leach of laterite for nickel, bio-leaching, heap leaching, SX-EW etc are being adopted to achieve the aims of the industry.

Jan 1, 2005