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By G. T. Lapidus, R. Zárate-Gutiérrez

Selective leaching of lead from a Pb-Ag-Zn concentrate with hydrogen peroxide in citrate solutions was studied at room temperature. Leaching tests were performed, varying the H2O2 concentration and the solid-liquid ratio, holding the solution pH constant at 7, and the citrate concentration at 1 M. Lead extractions of 100 % were achieved with 4 and 5 times the stoichiometric quantity needed to form elemental sulfur, with only a small amount of metal impurities dissolved (Ag, Zn and Fe). The lead solubility limit at those conditions was found to be ~21 g L-1. X-ray diffraction analyses of the leach residues were free of galena (PbS), while other metal sulfides, such as sphalerite (ZnS), chalcopyrite (CuFeS2) and pyrite (FeS2), were basically unaffected.

Jan 1, 2014

By BRIAN HITCHON

Calcium, magnesium, bromide and iodide extraction from formation waters for use as industrial minerals has occurred in several countries, but not yet in Canada. Potential commercial brine fields exist in th e Upper Devonian Beaverhill Lake Formation of so uthern Alberta, and the Middle Devonian Elk Point Subgroup of north-central Alberta, f rom which calcium, magnesium and bromide are potential products. Iodide contents in fo rmation waters f rom the Upper Cretaceous Belly River Formation and the Lower Cretaceous Viking and Bow Island fo rmations in central and southern Alberta are at the lower range limit of commercial iodide-bearing formation waters elsewhere in the world. Available information is insufficient 10 outline potentially commercial areas in Alberta, but such info rmation can be most easily obtained f rom test borings for shallow natural gas. Lithium is not now produced commercially f rom formation waters but its content should be monitored in view of f uture increased demand for this metal.

Jan 1, 1984

By F. Richards

"The property of the Cariboo Gold Quartz Mining Company; Limited; is in the Wells-Barkerville district of Cariboo mining division. It consists of a group of 106 Crown granted mineral claims and fractions; and extends for over 6 miles along what is termed the Barkerville gold belt. The main portal and mine camp are half a mile south of Wells; which lies at the northeast end of Jack of Clubs lake and is reached by a 55-mile motor road from Quesnel; the northern terminus of the Pacific Great Eastern railway.Gold-bearing quartz veins were discovered on the surface in various parts of the property by different prospectors as far back as 1877, but the work that led to the formation of the present company was performed by Al Sanders in the year 1926. Sanders dug trenches and drove small adits on quartz veins containing gold above what is now known as the Sanders zone. Very little underground work has been done beneath the earliest known discovery-the B.C. vein. The Cariboo Gold Quartz Mining Company was formed in the autumn of 1926. The total production of gold from its beginning in 1933 to the end of 1944 has been as follows:"

Jan 1, 1954

By C. D. Anderson, C. G. Anderson, P. R. Taylor

"Rare Earths have become critical for our energy and materials driven society. While primary production must ramp up to fill growing demands, the recycle of these strategic elements must also be initiated. This paper will outline the potentials of and metallurgical technologies employed for Rare Earths recycle from various secondary sources.INTRODUCTIONWhen investigating the recovery of rare earths from secondary sources it is necessary to understand the nature of the sources to be processed. As of 2009, the USGS reports the distribution of rare earths by end use, in decreasing order, was: chemical catalysts 22%, metallurgical applications and alloys 21%, petroleum refining catalysts 14%, automotive catalytic converters 13%, glass polishing and ceramics 9%, rare earth phosphors for computer monitors, lighting, televisions 8%, permanent magnets 7%, electronics 3%, and others 3% (USGS, 2011). Additionally, it is reported that the amount of recycling was quite small and consisted primarily of rare earth magnet scrap, although with the sharp increase in the price of rare earths, and the potential shortage in supply, focus in this area is continually growing. Thus, the opportunities, whether realistic or not, are extremely vast in the recycling of rare earth containing materials. The following subsections will present methods proposed for the recycling of rare earths based on the feed material type.RECYCLING OF RARE EARTH MAGNETSCurrently, investigations are ongoing in the area of recycling production scrap and end-of-life materials in the rare earth magnet industry. The following techniques illustrate potential methods for the recovery of rare earths from secondary RE magnet sources.Recycling of Rare Earth Magnet Sludge by Selective ChlorinationDuring the production of neodymium magnets, a by-product of production is the so called “magnetic sludge”. This by-product contains high amounts of neodymium, thus a process for the recovery of Nd has been proposed. In this process the Nd present is selectively chlorinated/distilled by the addition FeCl2 via the following reactions."

Jan 1, 2012

By D. W. Li

Due to the ultrasonic testing and mechanical wind speed sensor have high requirement for the environmental of the coal mine, the charge induction wind speed detection method based on wavelet analysis is proposed. The same wavelet disturbance detection method is used at a fixed distance to obtain an induction signal to obtain a pass time, and then calculate the magnitude and speed of the wind. Simulation and verification experiments show that the method has application across a wide range of test speeds (up to 60 m/s). The metal probe causes little pipeline flow field interference. The method is particularly well-suited to dusty environment, and does not cause dust deposition through long-term operation. It can be widely used in coal mines for point wind speed continuous online testing.

Aug 1, 2013

By J. T. McGrath, R C. A Thruston

The structural changes which take place in polycrystalline copper under the action of alternating cycles of torsion stress were studied, using the optical microscope and the X-ray dif-fraction camera, and an attempt was made to correlate them with changes in the shape of the cyclic stress-strain curve. It was found that the period of work-hardening was less than one per cent of the fatigue life, and that persistent surface marking, which are assumed to be incipient or actual microcracks, occur upon completion of work-hardening. X-ray diffraction patterns revealed considerable grain distortion at the completion of work-hardening in specimens cycled at a high strain amplitude. This distortion became progressively less as the strain amplitude de-creased. Mechanisms for the completion of work-hardening and the formation of microcracks are discussed.

Jan 1, 1962

By R. J. Fruehan

Oxygen steelmaking (OSM) is not only the dominant steelmaking process but defines the structure of the industry. There are a number of myths regarding the future of OSM, which are false. These myths include that the EAF will become the dominant process in the near future, it is less costly to produce steel in an EAF and OSM is a mature technology and no new developments are occurring. These myths are shown to be false. Selected new developments are discussed such as post combustion, recycling of waste oxides, slag splashing and sensors.

Jan 1, 2004

By Lorrie Fava

Two needs in the mining industry, to enable overall process improvements, are open systems and network connectivity in underground mines. The Pando project, a collaboration between Symboticware, Vale and Xstrata Nickel, and supported by CEMI, addresses these issues, and leverages the solution platform to deliver intelligent applications. An open system is one that uses publicly available standards for its key interfaces. Vendor-neutrality and ease of information flow are two main benefits that result from the use of open systems. By facilitating the interoperability of systems, open systems allow information to be available when and where it is needed for decision support. Network connectivity in underground mines is typically limited, with hotspots in strategically chosen areas that are relatively static. Mobile equipment moving through a mining work cycle experiences intermittent connectivity; in this situation, seamless remote equipment monitoring is impossible. The Pando project establishes an open technology platform, adhering to the IREDES and OPC UA standards. It enables the collection and integration of information generated by mobile equipment? seamlessly while there is a network connection, and as a store-and-forward gateway to manage intermittent connectivity. The platform capabilities are leveraged to support embedded intelligent applications. This open platform, the SymBot, is a rugged hardware and software device. The platform complies with open standards for industrial automation and systems interoperability. The SymBot platform is capable of providing advanced real-time decision support at the device level, and is designed to be remotely configurable. Applications being developed through the Pando project include engine monitoring, a dynamic load weighing system, machine location monitoring and automated activity monitoring including production and maintenance reporting.

Oct 1, 2010

By S. G. Shabestari

Thermal analysis is a tool that is generally employed to predict the structure of the alloy before the actual casting is carried out. By cooling a sample of the molten alloy and recording the temperature-time curve, important solidification events may be analyzed by using the first derivative-cooling curve. In this research, strontium is added to (AS5U3G) 319 aluminum alloy and its influence on the formation of intermetallic compounds e.g. Al15(Mn,Fe)3Si2, Al2Cu, Al5Mg8Cu2Si6 formed during pre- and post-eutectic reaction have been investigated. Also any changes in solidification parameters such as temperature of Al-Si eutectic under cooling and temperatures of nucleation and growth of each phases caused by strontium addition, have been determined via the first derivative cooling curves. The effect of strontium on the formation of various intermetallic compounds has been studied by using very accurate thermal analysis equipment and the microstructures were analyzed using an optical microscope. The various phases reported in this paper were identified using Scanning Electron Microscopy (SEM) and linked to Energy Dispersive Spectroscopy (EDS). Formation of all pre- and post-eutectic phases was interpreted by comparing the phases formed in the microstructure and the reactions detected by using cooling curves. The results of this research indicate that thermal analysis technique can be used as an on-line process control in the production lines in aluminum casting industries.

Jan 1, 2004

By R. F. Sharpe

THE Bullion mine, in the famous Cariboo district of British Columbia, is situated on the left bank of the South fork of the Quesnel river, approximately three miles below the outlet of Quesnel lake. A good road leads 63 miles northeast to the property from Williams lake, the railhead on the Pacific Great Eastern railway. The mine may also be reached over good roads from Vancouver via the Fraser canyon, Ashcroft, Clinton, and the 150-mile house, a total distance of 407 miles. In the early days of placer mining on the South fork of the Quesnel, several rich bars were found. The 'pay' on one of these at the mouth of Dancing Bill gulch was followed up the gulch by a Chinese company, who proved to be the discoverers of the present Bullion mine. This Chinese company commenced working in 1884, in what was then referred to as the China pit. Although working under very primitive conditions, it is reported that, during the ten years they operated the property, they recovered in excess of $900,000 in gold. This somewhat large recovery was due to a local concentration, the result of Dancing Bill creek having meandered down that portion of the channel and washed off the overburden. In 1894, a syndicate composed largely of the Canadian Pacific Railway directorate of that time, with J. B. Hobson as their field manager, acquired the property, as the apparent magnitude of the operation was too great for the resources of the Chinese company. Mr. Hobson, during the first ten years of his regime, developed the mine into a large-scale hydraulic operation, and during that period, from 1894 to 1905, recovered approximately $1,234,000 in gold. In 1906, the property was sold to the Guggenheim Exploration Company, who retained Mr. Hobson as Manager and embarked on an extensive programme to bring in additional water. This project was never completed, however, work being suddenly abandoned in 1907 and the mine closed down. Shortly afterwards, the property was purchased by a small operator on what is believed to have been largely borrowed capital. This venture resulted in no production, but in much litigation, which eventually reached the Privy Council in 1920.

Jan 1, 1939

By Douglas C. Fraser

A DIGHEM survey was flown in the Belford-Montcalm Township area of Ontario in November 1975. This 600-linemile survey resulted in the detection of 134 EM anomalies. The Montcalm Township copper-nickel discovery yielded a single-line anomaly having a conductance of 154 mhos. This anomaly was highly visible because (a) it had the highest conductance in the survey area, (b) it correlated with a 175-gamma thumbprint-shaped magnetic anomaly and (c) it was isolated from long conductive bands. The deposit is a copper-nickel pyrrhotite body which occurs in gabbro and strikes north-south, parallel to the flight lines. The DIGHEM survey was flown north-south, because the exploration program was primarily concerned with locating copper-zinc sulphides in the east-west-striking felsic volcanics. The flight line passed close to the deposit and yielded a 9-ppm anomaly on the chart record. The computer analysis showed that a deposit of exceptionally high conductance (154 mhos) caused the relatively weak (9 ppm) anomaly. The ground follow-up program of magnetics and EM led quickly to the discovery drill hole, which penetrated the orebody in September 1976. Subsequent geophysical surveys consisted of horizontal-loop EM, pulse EM, magnetic and induced polarization surveys over an area of about 8 claims. In addition, a detailed DIGHEM" airborne survey was flown at a line spacing of 100 m to evaluate the entire property of 620 claims. This detailed survey yielded EM conductor maps and contour maps of resistivity, magnetics and enhanced magnetics.

Jan 1, 1978

By J. F. K. Brown

WHEN I first received the kind invitation extended to me by the Mining Society of Nova Scotia, I read over very carefully the suggested title-"The importance of long-distance planning and budgetting in modern methods of mining, and the advisability of working to some definite plan". I came to the conclusion that I might as well confess my inability to handle properly such a vast and intricate subject within the scope of any one paper. More properly, I think a round-table discussion should be indulged in-a sort' of symposium carried on in similar fashion to the World Power and Coal Conferences- you know, a committee for this, a committee for that, and, finally, a committee to see what the committees are doing. Weil, your Secretary's suggestion is just like that- much too comprehensive for any half-hour's presentation. As a paper, also, it either becomes too general and therefore uninteresting, or i.t descends into detail and describes means and methods to the end desired, which have little attraction because they were designed to meet quite different conditions than those my audience would mentally be considering. Of the two evils facing me, I have chosen the one that sticks to the generalities. Your Secretary's query almost automatically divides itself into two distinct phases: First, the importance, and second, the advisability, of planning. Let us dwell for the moment on the second, because, if we can prove advisability, that leads to desirability and, finally, to doing. Proving is the difficult part of the little problem. Here was something I, personally and as a mining engineer, had been battling for all my corporate life without being able to prove it to anybody. Then I saw the way out of that. I perceived I could put that little question of advisability on another basis altogether-:put it in the class of "coming- some day- soon" whether you or l or anybody else liked it or not; call it, if you please, mandatory, certain, necessary, enforceable planning. All of which means that the problem of advisability has rather suddenly become the very practical one of "how to do it". Why?

Jan 1, 1937

By A. Alfantazi, E. Asselin

"The corrosion of commercially pure titanium (CP-Ti) was studied from room temperature up to medium temperature (~160°C) under conditions relevant to medium temperature chalcopyrite leaching processes. The corrosion rates were measured by immersion and electrochemical tests in sulfuric acid. The influences of chloride, cupric and ferric ions on the corrosion rate and behavior were also investigated. Corrosion of the CP-Ti did not account for the total current density measured by linear polarization tests. The corrosion rates of CP-Ti under medium temperature leaching conditions were surprisingly high. The corrosion rate measured in ferric containing solution at 160°C was approximately 20 mm/yr.INTRODUCTIONTitanium exhibits excellent corrosion resistance in many aggressive environments because of the formation of a very chemically stable, highly adherent, and protective oxide film on its surface (Mitsuo et al., 2002). Because titanium is the only metal available at a reasonable cost that resists the high temperature corrosive slurries in many leaching processes, it is often chosen as autoclave liner material where it is subjected to severe conditions of acidity, temperature and pressure (Grauman and Say, 2000).A number of distinctly different hydrometallurgical processes for the pressure leaching of chalcopyrite have been developed and patented by various companies and they can be classified into low, medium and high temperature regimes (McDonald and Muir, 2007). For example, chalcopyrite concentrate may be processed at medium temperatures (115-175°C) and pressures of 800-2200 kPa (Dreisinger, D., 2006; Sahu and Asselin, 2011). The lixiviant may contain 20 to 55 g/L sulfuric acid, 8 to 12 g/L chloride ions, 10-25 g/L Cu2+ (Jones, 1995, 1997, 1999), and less than 1 g/L Fe3+ (Defreyne et al., 2005). The amount of these additions is determined by the grade of the ores and details are shown in Table 1."

Jan 1, 2012

By Richard E. Barrett

SOME YEARS AGO I was associated with a mining operation which, because of its isolated location, burned wood for heating purposes. Year after year the tractors and tucks hauled the cordwood in from the edge of the ever-growing clearing. Each year the cartage costs became greater. The degree to which transportation distances affect the economics of fuels obviously varies with many factors, but the main criterion is the amount of heat a unit weight of the fuel will produce. For in-stance, wood is limited in most cases to a haulage distance of a few miles. Coal can be shipped hundreds of miles, whereas petroleum and gas ?can be transported thousands of miles. The world is now on the brink of having a new fuel -uranium. It has the virtue of being so concentrated that transportation costs can, for all practical purposes, be disregarded.

Jan 1, 1958

By H. R. Banks

SHORTLY after the commencement of operations at the Sullivan concentrator, the use of a pilot table was instituted in order to present a visual control of various products by showing the amount of galena still present in the tailing from several stages of flotation. Among the products so treated, the final tailing was later included. It was sratifying to note that very little free galena was escaping, but a fine streak o a whitish mineral appeared at the concentrate zone. This mineral was identified as cassiterite. The amount was small and the newly recognized component in an already complex ore was considered primarily as of academic interest. However, the problem of recovering a usable metal was intriguing and, as opportunity presented itself in temporary lulls in research on Sullivan and other ores, the concentration of tin was a useful 'bit of knitting' to go on with. It was recognized from the start that the bulk of the mill tailing would have to be floated and the residue subjected to gravity treatment. Since one of the predominating features of Sullivan concentration operation has been the necessity of fine grinding, the problem of gravity concentration was thereby intensified. Several batch runs were made, and sufficient pulp was treated to produce about one ton of final tin concentrate assaying 67 percent tin. The overall recovery was under 30 percent and the estimated profit at full tonnage was only marginal. Testing was resumed several years later, when the price of tin again appeared attractive, in an attempt to develop a more compact plant with better recovery of tin. The weakness of the original plan of concentration was the large number of tables required to treat a feed so low in tin.

Jan 1, 1941

By H. Clare Horwood

"In the Red Lake area in northwestern Ontario the relationships between general structures and structures containing ore deposits are among the most unusual and most interesting of any in the Precambrian Shield. The more important orebodies, which are in the central-eastern part of the area, occur in a variety of rocks on the northeastern, eastern, or southeastern sides of a series of granite stocks. Other deposits in the western part of the camp also are structurally associated with granite masses .The relationships were determined in the course of general and detailed geological mapping by detailed analyses of the fracture patterns in the rocks adjacent to the orebodies. In every case it was found that the structures containing the ore were produced by compressive stresses from the direction of intrusion of the granite masses( 2).The Red Lake area lies in the Patricia part of the district of Kenora and is accessible by boat from Hudson or by airplane from Kenora, Sioux Lookout, or Winnipeg. A road from Vermilion lake, on highway No. 17, was opened in August, 1947.The first discoveries of mineralization in the area that proved to be of economic importance were made in 1925 by Lorne Howey and George McNeely for Haileybury interests and by Ray Howey and W. F. Morgan for Mcintyre-Porcupine Mines, Limited. Both prospecting ventures were organized because of information presented by Bruce(l) in his map and report for the Ontario Department of Mines. The discoveries, which were both along the same structure, a quartz porphyry dyke, later developed into the Howey and Hasaga gold mines. Other discoveries were made at intervals as a result of prospecting and development work on ground staked for its location."

Jan 1, 1954

By R. W. Allgood

"THE world-wide shortage of elemental sulphur, which became sharply apparent in 1950, has focused attention on the commercial exploitation of sulphur-bearing materials such as pyritic ores, sour natural gas, and smelter gases. Although there •are no known commercial deposits of elemental sulphur in Canada, there are vast quantities of these sulphur-bearing materials. The International Nickel Company of Canada and Canadian Industries Limited have for many years collaborated in an effort to develop economic processes for the recovery of sulphur from the smelter gas arising from Inco's metallurgical operation at Copper Cliff, Ontario. While sulphuric acid has been •produced at Copper Cliff for over twenty years, recent developments will result in a 60 per cent increase in acid production early in 1952 and, later in the year, in commencement of the operation of the largest single unit ever erected for the manufacture of liquid sulphur dioxide.The purpose of this paper is to discuss •briefly the general factors associated with the recovery of sulphur from the Copper Cliff smelter gases and to describe the sulphuric acid operations and the liquid sulphur dioxide development.Processes for the manufacture of elemental sulphur, liquid sulphur dioxide, and sulphuric acid from sulphur-dioxide-bearing smelter gases are well known and in some cases •highly developed."

Jan 1, 1952

By D. J. Farmer

Mining hoists are major components of any underground mine, however, the detailed design work required to get the actual power required for a particular hoist is outside the scope of preliminary feasibility studies. Nonetheless, a hoist is costly. Therefore, an accurate estimate is needed for the design parameters and the power required. There are two methods available, namely, the O’Hara method and the Society of Mining Engineers’ method. Tests were done for both methods employing nine friction hoists and 19 drum hoists currently in use at Canadian mines. The O’Hara method provided unacceptable results for both friction and drum hoists. While, the SME method was designed for American regulations and factors of safety which often differ significantly from Canadian ones, good results were obtained. The two relationships deter-mined were simply to add 5% to friction hoist design and to add 4% to drum hoist design. Modifying the SME method by these two factors will allow the hoisting system determined by the SME method to be within the error for a prefeasibility study.

Jan 1, 1997

By P. R. Geoffroy

Extensive and Intensive Prospecting As often pointed out, the search for new ore deposits may be carried on along two widely divergent lines. It may be either extensive or intensive. By extensive prospecting we mean a search for mineralized outcrops conducted over large and more or less virgin tracts of land, followed by a test of the practical value of any discovery made, the test being limited to the immediate vicinity of the outcrop. Extensive prospecting, was, in fact, the only policy known to the early prospectors. of the American continent and is still the rule in the remote sections of the Canadian Shield and in the African wilderness. It can be further characterized by the lack of emphasis placed on geological and other technical means as an aid to the search for ore. However, very little virgin ground is left, nowadays, for a man or a company to test their luck, and whatever is left is so remote from the necessary means of development that any new discovery will require considerable delay and expenditures to be amenable to profitable mining. On the other band, a great many of the favourable and still unexplored areas (and this is particularly true in Canada) are overburdened to such an extent that outcrops of bed-rock are extremely scarce and extensive prospecting is nearly impossible. Intensive prospecting, to the contrary, must be understood as a detailed search for ore carried on over limited areas in districts already known to be mineralized and covering regional structures whose relation to mineral deposits bas been estahlis.hed with a fair degree ot certainty. The search for deep-seated deposits in the vicinity of successful mines is a perfect example of intensive prospecting. As a matter of fact, the majority of the geologists employed by the mining industry are engaged in some kind of intensive prospecting.

Jan 1, 1950

By G. Banini

Prior to installation of High Pressure Grinding Rolls (HPGR) at PT Freeport Indonesia (PT-FI) a series of laboratory tests were carried out to determine the design parameters and also determine key performance indicators (KPIs) for the industrial unit. The design parameters derived from the lab test work were then scaled up to estimate the industrial capacity of the HPGRs to be installed. These parameters include specific power draw, specific throughput, and specific force, rolls speed, product size distribution and wear rate of the rolls. This paper compares the performance of the scale-up procedure against the installed industrial size HPGR. Overall, the specific throughput of the industrial size HPGR is higher by a minimum of 30% compared to the expected scale-up value. As a result of the high specific throughput, the specific power draw and grind sizes are below the scale-up expectations in the commercial application. The impact of these factors also contribute to a lower than expected wear rate on the industrial rolls. Installed rolls achieved a service life in excess of 18,500 hours relative to the target of 6,850 hours predicted from the laboratory testing.

Jan 1, 2012