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By A. M. Hill

"This is an account of the expansion of Texasgulf's Timmins concentrator by the building of a fourth circuit.The original capacity of the mine and concentrator was 3.6 million tons per year of ore. In 1974, Texasgulf decided to increase that capacity by about one third to 4.8 million tons per year. It was planned that the increased capacity would be available by mid-1978.The expansion involved work at the rninesite, increased railroad capacity, and a new circuit in the concentrator, and it is the concentrator expansion which is described here.In 1974, the minesite drew its ore from the open pit. The pit was being phased out and was to be replaced by No. 1 mine. To allow for the expansion, a second mine was required. The railroad was capable of handling 18 car trains. Its capacity had to be increased to 27 cars per train and this, in turn, required two new locomotives. Each of these alone cost half a million dollars.The concentrator building in 1974 contained the concentrating equipment and miscellaneous services (such as machine shop, warehouse, analytical lab). The grinding and flotation sections were divided into three circuits ('A', 'B', & 'C'). 'A' and 'B' circuits treated copper-zinc ore and 'C' circuit treated the much more difficult copperzinc- lead ore. This 'C' circuit had been modified over the years to implement improvements in the metallurgy."

Jan 1, 1979

By H. N. Tran, D. Barham

"A systematic survey of the appropriate literature in terms of phase equilibria and possible reactions involving deposits in Municipal Solid Waste (MSW) incinerators are analyzed particularly with respect to the theoretical first melting points of typical ashes and the possible presence of a liquid phase at the temperature of ash-metal interface. Conclusions are drawn on the basis of the possible presence or absence of various metal chlorides and sulphates in such situations, and their effects on the problems of fouling and metal corrosion. From preliminary results, it would appear that ZnCl2 is unlikely to be present in any molten phase which causes corrosion because it evaporates rapidly from such liquids. It would also appear that PbCl2 and, by inference, ZnCl2 will sulphate at relatively low temperatures if the flue gas contains SO2 and O2.IntroductionMunicipal Solid Waste (MSW) incinerators produce fly ash which deposits on heat transfer surfaces throughout the furnace, leading to corrosion and loss of energy recovery efficiency. Despite a massive amount of research carried out on the subject of corrosion in MSW incinerators, the problem of corrosion of heat transfer metal is still with us, and no definite over-all cause and effect relationship has yet been identified. In order to make a contribution to the eventual solution of this problem, the authors have examined the problem from the beginning, using their knowledge of fouling and corrosion problems in black liquor recovery boilers as a starting point.The incineration of MSW has been used for many years to reduce the volume of material sent to landfill (ash volume compared to raw waste volume), and, in most cases, to recover energy at the same time by raising steam The steam may be ""low- or high pressure/ temperature"" depending on its end use. The higher the steam pressure and temperature, the greater seem to be the problems with corrosion of heat exchanger metal, presumably because the metal must withstand higher surface temperatures.The chemical and physical composition of MSW is extremely variable, not only on a regional basis, seasonal basis, and day-today basis, but also on a minute-by-minute basis, due to the inhomogeneity of MSW. This makes it extremely difficult to define cause and effect relationships, because both cause and effect are transient in nature."

Jan 1, 1991

By A. Alfantazi

Recently, titanium and its alloys have been the materials of choice for the liner and internal components of autoclaves used to extract Ni and Co from laterite ores. There have been many corrosion incidents ranging from localized attacks due to scale formation or welding, to damage caused by pockets of concentrated acid. Most of the literature focuses on methods to avoid the corrosion altogether. Little has been published to increase awareness of the chemistry at these conditions. For this paper, a literature review of the thermodynamics of titanium was undertaken to decipher the slew of information available. E-pH diagrams were constructed from select data and compared with the results of electrochemical experiments. Since nickel laterite leaching takes place in sulphuric acid, and in many cases chloride concentrations are very high, the Ti-H2O, Ti-Cl--H2O and Ti-SO4---H2O systems were considered.

Jan 1, 2004

By Andrew J. Troop

"VAUGHAN THOMPSON designed the Thompson retrievable diamond drill wedge and reaming assembly in 1948. Since 1950, the Hudson Bay Exploration and Development Company, Limited has used the method extensively. The wedge, setting tool, and reamer have been modified slightly since they were first introduced. In 1951, Mr. Thompson designed the Thompson arc cutter. The purpose of this tool is to decrease effectively the diameter of the arc cut, using standard drilling tools. This directional drilling device is usually employed when a branch hole is desired. The Thompson arc cutter has been used with success at Birch Lake, Saskatchewan, at the property of Cuprus Mines, Limited, Manitoba, and at Thompson Lake, Manitoba.UsesThe Thompson retrievable wedge provides a simple method for:(1) Re-drilling lost core sections(2) Re-sampling sections of old holes(3) By-passing lost tools Correcting the direction of a hole(4) Drilling a branch hole to obtain intersections at a higher elevation than the original holePrevious to the spring of 1951, the wedge was used only for the first four of these purposes. Recently it has been employed extensively for drilling branch holes."

Jan 1, 1953

By P. Z. Caverhill

In this section of the province only the most meagre of surveys have been made and because these are not sufficient to determine with any degree of accuracy even the total forest area, the information presented in this paper is not complete. Area: -The area south of the Canadian National, and served by the Pacific Great Eastern, is roughly 38,000. square miles, 30,000 of which is classed as productive. This is approximately equal to the productive area of Norway, or half of Finland-or of 30 per cent of Sweden. It is larger than that of either Nova Scotia or New Brunswick. Eliminating from the productive area 3600 square miles of grass-land and areas capable of agricultural development, 26,000 square miles (16,600,000 acres) remains as absolute forest-land, as compared with the 55,000,000 acres of Sweden, the 37,500,000 acres of Finland, the 17,000,000 acres of Norway, and the 7,600,000 acres of Austria.

Jan 1, 1925

"THE GOLD MINING REGION of Timmins - Val d'Or, astride the Ontario-Quebec border, has long suffered the effects of rising costs during the period when the U.S. price of gold was fixed at $35 per ounce. The federal government, through such assistance programs as that set up under the Emergency Gold Mining Assistance Act (E.G.M.A. ) in 1948, has subsidized the gold mining communities of Canada for a total of over $300 million to March 31, 1972. Of this, the Timmins - Val d'Or ""gold belt"" has received more than twothirds, almost $220 million. In spite of these continuous subsidies, only 12 gold mines are still producing in the Timmins - Val d'Or belt, whereas 71 mines have received subsidies for some period since 1948. The vital question is how the communities previously supported principally by the mining of gold will survive in the long run, as many of the older mines either are already depleted or are quickly becoming so. With the rising price of gold on the 'free market in recent months, prospects look a little brighter for the time being. Even with the increased official price of U.S. $38, which made the maximum government subsidized price about $48 per ounce, gold mines have not sold any gold to the government since January 1972 and some stopped doing so months before that. The populace of the region has not been enthusiastic about relocation nor about extensive retraining programs in the past and probably will not be in the future. So, when the remaining gold mines become depleted, the old problems of community depression will remain."

Jan 1, 1973

By M. K. Senicie

IN July, 1937, Asbestos Corporation, Limited, installed an automatic conveyor-belt scale at their King mine, Thetford Mines. The equipment was purchased 'on trial' and its performance has proved entirely satisfactory to the staff. The scale was manufactured by the Toledo Scale Company, of Toledo (Ohio) and Windsor (Ont.) and was installed by one of the Scale Company's engineers. The electrical recording equipment was installed by Keith Mercer, Reg'd, of Montreal, Canadian agents for the manufacturers, the Builders Iron Foundry, of Providence, Rhode Island. The recording equipment consists of a duplex weight-transmitter attached to the scale-head, a duplex totalizer with differential relays, a belt-speed compensator, a rate-of-delivery recorder, and a rate-of-delivery indicator. As it was desired to run the mill at maximum capacity, it was necessary to know the rate of feed at all times, so that any lessening of rate of feed or delays would be recorded and could be corrected. After having determined the rate of feed to the mill (100 per cent capacity), it was required to have weighing and recording instruments which would show: (1) The rate of feed per hour. (2) Any variations .in the load. (3) Any delays and the duration and time of the delays. Rate of tonnage recorders in the mill superintendent's office and at the point of feedi.ng were necessary, as was automatic control between the mill superintendent and the feed man. It was desired to have a permanent record of total tonnage fed per shift or day; weighing and recording mechanism had to have sensitivity to record all previously mentioned conditions. Mechanism had to be of rugged construction, and be so built that it would stay in good operating condition, with the minimum amount of adjustment and supervision.

Jan 1, 1938

By C. D. Smith

Numerous studies have shown the potential of air rate profiling to significantly improve the flotation performance of a bank of cells. To date many profiles have been implemented; balanced, increasing, decreasing and combinations of these. Previous work has typically shown using an increasing air rate profile, where the air rates are increased proportionally to each cell down the bank, yields a higher grade for a given recovery compared to other profiles. Air rate profiling can then be thought of as having two distinct components; determining the correct distribution of a given volume of air and, perhaps more importantly determining the correct total volume of air to add to the bank. To date no method for this second component has been established. In an alternative technique the air rate to each cell is adjusted in order to optimise the air recovery from that cell. Air recovery is the fraction of the inlet air which overflows the weir of a cell as unburst bubbles. The peak in air recovery (PAR) is a robust measurement that indicates optimal performance for the operating conditions in the cell, and sets the PAR air rate. By doing this for each cell in the bank, the optimal total air rate to the bank and the optimal distribution of that air can be simultaneously determined. In this study plant trials evaluated different air rate profiles, and profiling based on PAR. The total air rates to the bank for all profiles tested were approximately equal, allowing direct comparison. The results showed that the highest cumulative mineral recovery was achieved by operating at air rates which gave the PAR for each cell down the bank. Different distributions of the same total air rate to the bank gave the same cumulative upgrade ratio, but lower cumulative recoveries. In this study, the increase in cumulative mineral recovery, at the same upgrade ratio, was more than 33%. Peak in air recovery (PAR) based optimisation of air rates to banks of cells and to the individual cells has been shown to significantly improve flotation performance as it simultaneously determines the optimal air rate to the bank, and the optimal distribution of that air.

Jan 1, 2009

By Jonathan Peck, Jim Gray

"With the implementation of more advanced monitoring, control and locating systems in surface mines, there is an ever increasing need for their mine-wide integration toward achieving over-all optimization. AQUILA Mining Systems Ltd. is developing the basis for a comprehensive real-time monitoring, control and information system called the Total Mining System or TMS. This system is being designed to address both current and future needs of open pit mines toward improving productivity and minimizing costs, through better two-way information flow between each component in the operation. At a basic level, feedback from equipment and process monitoring will enable decision making to be based on quantitative, on-demand information, thus permitting proactive rather than reactive planning. Dynamic planning would be a valuable tool as market conditions fluctuate, equipment fleets age and variations in the grade, quality, geometry and hardness of the mined material all contribute to either changing production targets or levels of achievable performance. Such a capability could be implemented within the next two years.At a higher level, and within five years, autonomous operation and/or real-time supervisory control of mobile and stationary equipment in open pit mines will be achieved. A discussion is provided in regard to the development and implementation of an autonomous haultruck and blasthole drill, to demonstrate the need for such a system.This paper outlines a preliminary program for the design, development and implementation of this system, primarily in relation to high-level communications and its role in the future automation of open pit mobile equipment."

Jan 1, 1995

By R. W. Diamond

Introduction THE Sullivan mine and the milling, smelting, and refining operations of the Consolidated Mining and Smelting Company are sufficiently well known to make unnecessary anything more than a very brief account of the events which led up to this Company's branching out into the chemical industry. This development is the result of the 26 per cent sulphur content of the Sullivan ore. Seventy-five to eighty per cent of this sulphur enters the mill tailing, which is stocked at Kimberley. The remainder, contained in the lead and zinc concentrate, is burned off in the first treatments at Trail. Prior to this new development, the sulphur gas was wasted to the atmosphere. In spire of its great dilution with air and discharge from stacks at high elevations above the plant, some damage to vegetation close to the plant was experienced. It had always been apparent that this sulphur should be recovered and utilized if possible, at the same rime relieving, or curing, the smoke nuisance, and constant studies with this in view had, therefore, been maintained. One of the early conclusions reached was that the Canadian prairies would ultimately require large quantities of phosphate fertilizers, as had been the experience of older countries, and that these fertilizers would constitute a large outlet for sulphuric acid which could be made from smelter gases. This conclusion prompted a widespread search for phosphate rock, particularly in British Columbia and western Alberta, with the result that low-grade beds were discovered in the Crowsnest district and to the north therefrom through extensive areas (1). Following these discoveries, an experimental plant was built at Trail for the production of triple superphosphate in order to facilitate field-tests in fertilizing prairie lands.

Jan 1, 1934

By Peter C. Jones

Owing to the inadequacy of the ore transport system at Cassiar in the late 1960's, a new facility was required. This paper traces the various alternatives considered and gives a description of the tram line as installed. The problems encountered, changes made and future modifications are discussed in detail, together with the effects these have on maintenance and operations.

Jan 1, 1978

By Yongfeng Jia, Shaofeng Wang, Danni Zhang

Ferrihydrite is ubiquitous in soils, groundwater and aquatic sediments and is usually classified as "2-line" or "6-line" according to the number of diffuse XRD peaks. It has high surface area and reactivity; therefore, it may serve as a sink for sequestering trace metals, metalloids and organic matters via adsorption and co-precipitation. Although considerable attention was paid to the transformation process of this thermodynamically metastable solid, there are still some controversies on the mechanisms of the formation of goethite or hematite from the ferrihydrite precursor. This work systematically investigated the transformation of 2-line ferrihydrite produced by using different neutralization regent (CaO vs. NaOH) into crystalline products at different pHs (4, 7 and 8), three temperatures (25, 40, 75 °C) and in different media (sulfate vs. nitrate). X-ray diffraction (XRD), Raman, Fourier transform infrared spectroscopy (FTIR) and chemical extraction were employed to characterize the transformed solids as well as the redistribution of Fe between the amorphous and more crystalline phases. The results showed that the transformation product in nitrate media was hematite (major) and goethite (minor), which was independent of pH, temperature or neutralization reagent. In sulfate media, goethite was the dominant solid under slightly acidic conditions (pH 4) with 6-line ferrihydrite as the intermediate product, whereas neutral to slightly alkaline conditions still favor the formation of hematite. Chemical extraction results indicated that there was only ~3 % of amorphous phase detectable after aging at 25 °C for 280 days at slight acidic pH. In contrast,~70 % of the iron remained as an amorphous phase under neutral to slightly alkaline conditions. The results suggested that the pH as well as the reaction media (sulfate ion) plays an important role in the 2-line ferrihydrite transformation process.

Jan 1, 2016

By Seppo Haapamaki

"Since it started production in 1970, Anderson Lake Mine has experienced several radical changes in mining methods as a result of the physical characteristics of the ore zone along with the need for improved productivity. This paper examines the transition from longhole open stoping to mechanized cut-and fill then to vertical crater retreat at Anderson Lake Mine. The reasons for the need to change mining methods is analyzed taking into consideration the impact of such criteria as improved productivity and ground conditions and how these criteria affected the over-all economic viability of the mine. IntroductionAnderson Lake Mine is one of five producing copper mines in the Snow Lake area and is situated approximately 3 km southeast of the townsite of Snow Lake (Fig. I).The mine production rate at Anderson Lake is 700 tpd and all ore is trucked from the mine to the mill located approximately 2.5 km from the mine site . The mine is serviced by a three-compartment shaft sunk to a depth of 3300 ft with level spacings at 175 ft and 150 ft intervals from the 600 ft level to the 3000 ft level. .The shaft was collared in 1965 and, a year later, the hoist and compressors were installed. By 1969, a crusher system had been built and actual production began in 1970. During 1978, production was suspended for the year to allow for 430 ft of shaft deepening."

Jan 1, 1988

By W. S. Fyfe

Gold is mobilized and precipitated in a wide variety of environments ranging from those of weathering and biological phenomena, to pluton emplacement to deep metamorph ism . But it appear that pervas ive leaching of large rock volumes fo llowed by the focussed di charge of typically low salin ity flu ids is frequently involved. There are great gaps in our knowledge, particula rly with re pect to gold in very high temperature fl uids generated at near Moho depths. But uch flu id may play an important part in Archaean pluton associated lode gold deposits whe re ultra high temperature fluids, rich in C02-CO-COS, may be associated with magma underplating and crustal assi mil ation processes (sag subduction) associated with very den e ult ramafic magma . Other environment with great potential include those of major thru t fau lt and strike slip fa ult s where large quant ities of fluids are mobilized .

Jan 1, 1986

By S. E. Wolfe

The presence of helical ribs in smooth-bore round pipe results in the transport of granular solid particles m water at a much lower velocity than required to transport the same solids in a smooth pipe. The helical motion imparted to the flowing mixture effectively returns settled solid particles to the main stream. The flow may be stopped and restarted without difficulty. Due to the lower velocity required for satisfactory transport large power savings are realized. Also: due to lower velocity, the wear on the pipe walls is much reduced. For satisfactory performance, the ribs should have a high angle relative to the long axis of the pipe and the lineal spacing between adjacent ribs should be modest.

Jan 1, 1967

By A. H. Anderson

THE travelling grate coking process was developed by Shawinigan Chemicals, Limited, at their Shawinigan Falls plant. The first production unit went into operation a month prior to the outbreak of the war. Since then a substantial part of the coke used in the manufacture of calcium carbide has been produced by this process. In the following will be given a short account of the development work, a description of the process and the equipment, a discussion of the properties of the coke, the economics of the process and its future possibilities. EXPERIMENTAL WORK The carbide industry is a large consumer of coke, one ton of commercial carbide requiring for its production 1,200 lb. This coke must meet certain specifications in order to be acceptable. It should have a low ash content, preferably below 8 per cent, and the sulphur and phosphorus content must not be above specified limits. The size of the coke is also important. If it is too large it has to be crushed before it can be used in the furnaces, and if it is too fine it may have to be screened and briquetted. In addition, it must be dry. Although it was generally possible to purchase coke, including petroleum coke, and coke fines, in the quantities required, it became increasingly more difficult as time went on to obtain coke of a suitable quality at an attractive price. It was therefore natural for us to look to coal carbonization as a means of basing the supply of the fundamental raw material for carbide manufacture on something more solid than the shifting conditions of the coke market.

Jan 1, 1944

By Sherwin F. Kelly

"THE TITLE I have chosen is certainly not one of those self-explanatory ones. I shall endeavour to make its significance clear during my remarks but, in the hope of minimizing that inevitable exodus which follows a good lunch such as this, I am going to withhold the final key to its meaning until the very last sentence of this talk.Some explanation is due at the beginning, however, so for those of you unfamiliar with Spanish I will explain that casa means house, or home. The casa about which I am going to talk necessitates a wide .and generous interpretation of the word, because I am using it to indicate principally that portion of the North American continent which is the home, in the western hemisphere, of British and American ideals of justice and freedom, the dignity of the individual and his right to exercise private initiative .and engage in private enterprise. In a wider sense, I am including the entire western hemisphere, which may yet stand as the last bulwark of political and industrial democracy.As for the treasures of which I am about to speak, may I remind you that there are no• material treasures but those derived from the earth, and they are derived by one of two processes, -mining and farming. These two fundamental industries are the basis, and the sole material basis, of our welfare, our wealth, our very existence. From farming, whether it be farming of the land. or farming of the sea, we obtain the food to keep us alive, healthy and able to work."

Jan 1, 1955

By R. M. Kalanchey

The application of pressure oxidation processes to copper feed materials has gained increased exposure in recent years and some of these processes have made commercial inroads, although rather limited to date. Among the hydrometallurgical processes with significant commercial potential, Dynatec's copper pressure leaching process has been applied to arsenic-bearing copper materials and has shown, through a number of batch and continuous test programs, that pressure oxidation is a technically feasible option for the recovery of copper with coincident sequestration of arsenic in an environmentally benign residue.

Jan 1, 2007

By D. A. Temple, G. O. John

Until recently, the approach to the problem of treating complex ores bas been to produce, insofar as is possible, mono-metal concentrates which are treated in traditional zinc, lead and copper smelting circuits, with the residues and by-products from some of these circuits being retreated for the recovery of contained values either by a separate residue treatment process or along with the primary feed to the appropriate circuit. The continued development of the Imperial Smelting Process, with its ability to treat poly-metal concentrates, calls for a re-examination of the traditional approach to this problem, and this the paper attempts to do. A survey of recent progress in the technical development of the process is made and a summary of current operational performance is included.

Jan 1, 1971

By Matthew Scott

Introduction The refining of precipitate is the final stage of all the processes involved in gold mining and cyanide milling, by which the precious metal is at last obtained in a concentrated form, which can be accurately valued and marketed. Possibly one ought to say, conveniently shipped, for accuracy in valuation depends in many instances on a toughening treatment given the bars as received at the Mint so as to obtain a homogeneous metal that lends itself to representative sampling; which, of course, entails a surcharge on the regular Mint charges for the extra work necessarily undertaken. There are several methods of refining zinc-gold precipitate, each with its advocates; the method employed depending not always on the quality of the bullion produced but on the local exigencies of the case in point. These methods are more or less detailed in various textbooks and it is not the purpose of this paper to discuss them, but to confine ourselves to the specific case as stated in the title of the paper. At the outset, it behooves the writer to express his thanks to Mr. Brigham, the General Manager of the Hollinger Mines, for the kindly consideration and encouragement given in developing this process. This will be better understood when one considers the immense values involved, tending towards conservatism in practice, and making one chary of radical innovations. This process has been in satisfactory operation now for about two and-a half years, during which time over twenty-five million dollars value in fine gold has been produced, so that it may be reasonably held that the process is successful.

Jan 1, 1931