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By C. M. Diaz, S. W. Marcuson

In the late 19th century, the discovery of rich nickel-copper sulfide ore bodies in Sudbury and the need for tonnage quantities of the metal to be used in nickel steel armor provided the foundation for establishing the Canadian nickel industry. For almost 50 years, International Nickel was the key player. In 1930, Falconbridge Nickel entered the field. These two companies remain the key Canadian nickel producers. This paper discusses the factors that have influenced the evolution of nickel smelting processes. The initial Sudbury ore smelting and nickel copper separation technologies were imported from abroad. It was only in 1937 that International Nickel established a process research laboratory in Copper Cliff The explosive post WW II industrial development created a strong demand for a broader variety of nickel products. For both International Nickel and Falconbridge, R&D became an essential business tool to succeed in the new market scenery. In the last few decades, new technologies were developed and commercialized to respond to the raising cost of energy, society pressing environmental concerns, the advent of nickel laterites as an important source of new metal, the incorporation of new nickel producers to the market, and, therefore, the need to increase productivity. Canada thus became an important exporter of technology. In this paper, the authors review this history with the objective of highlighting the forces that have triggered the most important changes in Canadian nickel smelting.

Jan 1, 2005

By Joan Weinberg

The real gross national product (GNP) expanded by 2.3% during the second quarter, down from the anomalous 4.4% growth rate in the previous 3 months. If the expansion continues through October, it will have lasted 5 yr and become the second longest in 40 yr.2 As in the first quarter, improvement in U.S. exports played a role in the continuing--albeit slow--growth. More than 2 yr of declines in the dollar relative to currencies of other industrial countries have contributed to a slight reduction in the trade deficit in real (volume) terms, as real net exports of goods and services rose $1.9 billion (table 1). Exports grew a strong 12.1% while imports, which had fallen the previous two quarters, rose 7.4%. Manufactured goods and petroleum products accounted for most of the second quarter import increase. The American Petroleum Institute estimates that the volume of crude oil and refined products imports in the first half of 1987 surpassed those in the same period last year by 7.5%, reflecting falling domestic production and higher than expected demand. Expenditure on durable goods--those that last at least 3 yr-by both consumers and producers also contributed to the second quarter expansion. Personal consumption of durable goods rose 9.0%, after having fallen the two previous quarters. Motor vehicle purchases accounted for most of the second quarter increase and the first quarter decrease. Sales of automobiles surged in the last quarter of 1986, as consumers rushed to capture the sales tax deduction that was eliminated on January 1. Sales fell in the first quarter of 1987, but have now moved closer to the trend line exhibited in the first three quarters of 1986. Automobiles accounted for half the 0.8% July gain in retail sales, and two-thirds of the 1.4% June gain. Producers durable equipment purchases also rose this quarter, accounting for the increase in nonresidential fixed investment.

Jan 1, 1987

By R. S. Dean

In an earlier paper Dean and Hersberger5/ gave preliminary results a d discussed briefly the use in flotation of organic reagents of the type known in the textile industry as "wetting agents.? These reagents are those with a molecular structure comprising a long hydrocarbon chain attached to a. highly molar or hydrorhile group in such manner that ionization is nearly complete in dilute solution and the resultant ionic grouping has a very considerable hydrophile-lipophile unbalance in the structure. As a result of this characteristic structure these reagents are more or less powerful frothers and emulsifiers. Ten the degree of hydrophile-lipaphile unbalance is sufficiently great and specific chemical factors are absent these compounds behave in flotation as noncollecting frothers insensitive to reason¬able changes of pH.

Jan 1, 1937

By R. S. Dean

In an earlier paper Dean and Hersberger5/ gave preliminary results a d discussed briefly the use in flotation of organic reagents of the type known in the textile industry as "wetting agents.? These reagents are those with a molecular structure comprising a long hydrocarbon chain attached to a. highly molar or hydrophile group in such manner that ionization is nearly complete in dilute solution and the resultant ionic grouping has a very considerable hydrophile-lipophile unbalance in the structure. As a result of this characteristic structure these reagents are more or less powerful frothers and emulsifiers. Ten the degree of bydrophile-lipaphile unbalance is sufficiently great and specific chemical factors are absent these compounds behave in flotation as noncollecting frothers insensitive to reasonable changes of pH.

Jan 1, 1937

By J. M. West

Increased leisure time and increased interest in the out-of-doors is leading more and more families to experiment with placer mining of gold, and some- times even to going on into small-scale production. This Bureau of Mines report supplies basic information un areas of occurrence, equipment needed, prospecting, sampling, mining, and regulations concerning the possession and sale of gold. Selected references are given for further study.

Jan 1, 1971

By J. J. deBarbadillo

This Bureau of Mines report describes a process for recovering chromium and other metals from superalloy scrap. Laboratory-scale experiments were conducted to test a complex flowsheet utilizing a wide range of extractive metallurgical operations. The novel basis for the process is the fonnation of a sulfide matte in which chromium is concentrated in a discrete chromium sulfide phase. Mineral processing and hydrometallurgical procedures are used to separate chromium sulfide from the other matte constituents. The products of the process are a chromium-nickel alloy suitable for reuse in the superalloy industry, electrolytic nickel, electrolytic cobalt, and iron-molybdenum residue. Recovery of the principal elements contained in the scrap is chromium--93 percent, nickel--99 percent, cobalt--96 percent, and molybdenum--92 percent.

Jan 1, 1981

By Ivor Hawkes

The purpose of the development described in this report and as stated in the contract work statement is to "design, develop, fabricate, test and demonstrate, and deliver to the government permissible low cost cylindrical stress gauges and associated components capable of measuring change of stress as a function of time in underground coal mines. The cylindrical stress gauges shall be suitable for installation in bore holes". The technique adopted for measuring rock stress changes is to preload a steel cylinder diametrically across the sides of a 1-1/2 in diameter bore hole and detect deformation of the cylinder from stress changes in the rock, by means of a vibrating wire transducer. By calibration, changes in the period (time for one wire oscillation at the natural frequency) of a high tensioned wire stretched diametrically across the cylinder in the direction of load application are related to stress changes in the rock. To completely evaluate the stress field change in the plane of the bore hole, three gauges set at an angle to each other are required.

Jan 1, 1973

By Robert Torbin

The objectives of the Continuous Shaft Lining (CSL) System are to reduce the costs, safety hazards, and time currently required in lining mine shafts with concrete. The CSL will line machine bored shafts downward from the shaft collar on a continuous basis using an inverted, pressurized slipforming technique. The technique for slip-forming downwards has been demonstrated and refined under this program. The approach taken involved laboratory scale testing of key features of the CSL concept. These feature tests included concrete distribution, concrete sealing, concrete slipforming and development of a reliable concrete mix. Based on these results, a full scale above-ground test facility and CSL were designed and fabricated. The objectives of these tests were to demonstrate the viability of the basic concept; to establish operating limits; and to provide input data and information for the design of a second generation shaft lining system. The results of the program have led to a CSL design and operational philosophy which will need to be tested in an underground environment before industry will accept the technology. However, the next generation CSL promises to meet all the original program technical objectives.

Jan 1, 1983

Jan 1, 2003

By John W. Taber

The Bohemia mining district is a small but intensely mineralized area in western Oregon . For its size , it has made a substantial although somewhat sporadic production of gold throughout a long period of years . The veins also contain lead, zinc , and copper, but in the past these metals have not been recovered in important amounts . In reviewing the progress of mining activity in the district , an effort has been made to gather under one cover all available information on former operations , including methods of mining , production, and geology pertinent to the ore deposits , problems encountered, and other factual data that may affect future mining in the district . A special effort has been made to assemble as many maps of former workings as possible in order that these may be preserved and readily available to assist in future exploration. The data presented herein are based on brief reconnaissance examinations made during several weeks spent in the field in September 1946. These are supplemented by information obtained from various individuals actively or formerly connected with operations in the district . Only the principal properties and several of the more outstanding prospects were actually examined. Many of the older workings were inaccessible.

Aug 1, 1949

By J. J. Forbes

Problems connected with the incidence, effects, determination, and control of dusts are still much before the public, although more information is available to the layman than when Bulletin 400, of which this publication is a revision,5 was issued in 1937. Bulletin 400 attempted to assemble information in convenient form on various phases of the dust problem, largely in the mining and allied industries. This revision includes data that have accumulated since 1937 and some that appeared previous thereto but were not available to the authors at that time. The literature on this subject is so voluminous that no attempt has been made to include all published material or all types of dust diseases, but only to assemble some of the more outstanding data on several aspects of the subject.

Jan 1, 1950

By Tony Treasure, Ian Ewart

The EMEW® cell has been developed to overcome a number of inherent limitations in conventional electrowinning technology, particularly the high cost and restricted process windows characteristic of conventional hardware. The EMEW technology has been widely demonstrated to achieve high performance for various metals under chemical conditions well outside the limits required for efficient operation of conventional cells. In particular application of the EMEW cell for recovery of silver offers significant operating and capital cost advantages over conventional Merrill Crowe technology used for cyanide based solutions. The cell also offers process advantages for direct silver recovery from nitric acid solutions. The performance of the EMEW® cell on silver cyanide solutions, producing high grade silver metal in a single step, is accomplished by providing a physical mechanism which presents metal ions to the cathode on a highly efficient and continuous basis. The simplicity of design and operation of the EMEW cell offers the following advantages for silver recovery from cyanide or nitrate based solutions: • High grade product in a single step. • Selective for silver over other metals in the electrolyte. • Wide operating concentration range (100,000 - 5ppm). • Ability of the cell to operated in a variety of acid or alkaline electrolytes. (Cyanide, Nitrate). • Simple liquor reticulation. • No pretreatment required - Clarification, deaeration or zinc dust. • High cmTent density and current efficiency compared to conventional electrowinning cell. • Modular design allows for flexible operation and production rate. • Pilot plant results using full scale cell result in accurate scale up design. • Easy/fast installation - cell banks are delivered pre configured with piping and wiring. • Enclosed cell minimizes corrosive vapor and liquid losses in the circuit.

Jan 1, 2000

By Z. T. Bieniawski

Geomechanics signifies the science and engineering of soil and rock materials and of rock masses. It is a field of professional practice and research that draws heavily on the elements of soil and rock mechanics. Geomechanics contributes to a number of disciplines: mining engineering, civil engineering, geological engineering, petroleum and natural gas engineering, and engineering geology (including the elements of geohydrology and geophysics). These disciplines are involved in the design and construction of such projects as mines, tunnels, foundations for structures, excavated rock slopes, dams, shafts, boreholes, oil reservoir wells, underground storage facilities for oil and gas, and hazardous waste repositories. Geomechanics allows us to improve both our environment and our quality of life. In the context of this Handbook, the scope of geomechanics is discussed mainly from the point of view of applications to mining engineering. However, the coverage of the subject mate¬rial is so comprehensive that it is relevant to other disciplines as well. Section 10 covers the field of geomechanics in a structured fashion, beginning with the fundamental principles and leading into practical applications in mining engineering. Throughout the treatment of the subject, knowledge of geologic conditions is assumed since this is discussed in other sections of the Handbook. An important feature of this section is a series of practical examples illustrating the various aspects of geomechanics. Since geomechanics is concerned with both soil and rock mechanics, Chapter 10.1 introduces the fundamentals of soil

Jan 1, 2008

AS I told you before in the treatise on ores, once these are found (whether they are ores of metals or semiminerals) it is necessary to assay them in order to know what is in them, since the judgment of the sight is not sufficient for recognizing the quantity or even what substance they contain. For this reason, it is necessary to come to assaying and, with the knowledge of experience, to weigh their virtues and to proceed with the work or withdraw from it and its expense; and also through knowledge to make provision for their defects if some evilness harms the ores. For if you should have need of a thing that would help them and should not find it, all that you have done would be lost; and, on the other hand, if you should find that the ores are abundant and rich and easy to smelt, you take courage to continue without respect for anything. Therefore, in the following book I shall tell you first in general how the assay of all the metals should be made. I shall enlarge in particular on silver more than on any of the others since it is more important. Then I shall tell you how the ores should be prepared for smelting and also how blast furnaces and other furnaces for smelting such ores should be constructed, and finally how all elemental mixtures of metals are to be separated one from the other with the ability and power of art, and how they are reduced to their final perfection and fineness according to their species.

Jan 1, 1942

By O. C. Irwin

For several years the C. F. & I. Co. men have been working on a fan signal and many different schemes have been tried. I will describe a few of them. A make-and-break attachment was placed on the fan shaft which caused a light to flicker. A hinged door was placed on air course and counter balanced so that it would have a slight travel when the air pressure was reduced an appreciable amount. This motion was used to open the power circuit, blow a whistle, or ring a bell. Series transformers were placed in motor leads of fan drive motor and the variation in amount of power to motor was used to control the fan signal through a magnet or relay. A governor was placed on the fan shaft which opened a signal circuit when speed of fan was reduced. We tried to produce a machine actuated by the volume of air, (that is on the principle of the anemometer) but had to discard this due to its being too delicate. None of the above schemes seemed to fill the conditions which the State and our Mine Inspector wanted covered. They gave us the following demands for a signal: 1. Must open mine circuit and sound alarm when air pressure was reduced below a certain amount. 2. Must be fool proof. 3. Must work on any kind of fan drive (steam or motor). 4. Must be safe to ' install- in any mine or fan house. 5. Must not depend upon mechanical device which could become inactive due to friction or other causes. 6. Must be as simple and easy to adjust as possible.

Jan 1, 1925

By S. Afshar, E. Dajoux, C. Allaire

For various reasons, molten salts, mainly chlorides and fluorides, are used in the aluminum industry. In the holding and melting furnaces, these salts may have different roles such as protecting the metal from oxidation, reducing the metal content of the skim or removing inclusions or impurities from the metal bath. However, the use of these salts may also have some undesirable effects such as easy attack of the furnace lining refractory materials by molten aluminum. The aim of the present investigation was to clarify and to compare the effects of chloride versus fluoride salts, on the corrosion process of the aluminosilicate based refractory materials. A laboratory test and procedure, simulating the conditions at the metal line in the aluminum treatment furnaces, was used. Different aluminum alloys (A1-5wt.%Mg, A1-5.5wt.%Zn and 7075 alloy) and chloride or fluoride salts (MgC12, KC1, CaCl2, NaC1, MgF2, CaF2, NaF and cryolite) were used as well as several aluminosilicate materials. Thermogravimetric measurements were also carried out in order to analyze the effect of the salts on the oxidation of molten aluminum alloys. The experimental results showed that fluoride salts are more aggressive than chlorides against the tested refractory products. It is postulated that the fluorides prevent the formation of a protective oxide layer on the metal surface, favoring at the same time the corrosion of refractories. Moreover, it was found that the presence of Na in fluoride salts increases significantly the aggressiveness of the aluminum alloy towards the refractory samples.

Jan 1, 2004

JOHN.B. HASTINGS, Los Angeles, Cal. (written discussion).-This paper reminds me that when I had an option on a Nevada mine, where the only orebodies assayed $4 gold, I went to San Francisco to learn the cost of putting broken ore in a 25-ft, vein on the mine cars, and sought Mr. Alfred Wartenweiler, who said "There is not a mine in California that can tell what it costs to move ore in the stopes." When building small mills in the mountains, and with only 30 or 40 employees, by entering in a log at night the work performed by each man, I have been able to plot the costs with the accuracy shown in this paper, and very good discipline it is. Cost of new construction and repairs is carefully kept by most companies, and is compiled after completion; probably the outlay of labor and material in pieces of work sufficiently important to call for blueprints is estimated beforehand, but numberless odd jobs of construction and repairs are so itemized. . Might it not be worth while, at a large plant, to have these smaller daily tasks described in advance in a central repair office, and then let inspectors look over the job, report time and material needed, and enter it in sufficient detail in proper ledgers, the men then being sent to accomplish it, and reporting when finished? The forecasts would soon be made quickly and correctly and would give the head mechanic, carpenter, and electrician easy supervision of their men, and the results could be seen at a glance by the managers.

Jan 4, 1918

By Gaifeng Xue, Jingxuan Zhou, Shangchao Liu

"Both COD and TOC can characterize organic pollution of coking wastewater. In theory, there is a linear correlation between these two indicators. After continuous monitoring TOC and COD of coking waste water, linear regression relationship between of these to indicators was studied with the use of mathematical statistics. And conversion equation between these two indicators was established, and using t-test method for significance testing. The results showed that the linear relationship of COD and TOC was significant. Also interval estimation of equation slope and intercept were given in the condition of 95% confidence level. A linear regression equation established can be used to indirectly convert TOC to COD with high precision and accuracy.IntroductionBoth chemical oxygen demand (COD) and total organic carbon (TOC) are measure of the degree of characterization for organic pollution of water bodies. The current COD standard analytical methods is Potassium dichromate titration method [1] . there are some disadvantages in this method, such as only part of organic matter in the water bodies being oxidated, the refluxed steps, a long time needed for each measurement, high cost. It is the most important that sulfuric acid silver and mercury sulfate reagents used in the measurement may easily lead to secondary pollution. In contrast, the measurement of TOC is by the method of combustion or Photocatalytic Oxidation. The result could be easily got from the instrument. There are some advantages in this way, such as easy operation, short time and little expenses for each measurement and no secondary pollution 121• In addition, the measurement of TOC has higher degree of precision and accuracy than the measurement of COD both in the determination of calibration standards and actual samples. The meaning and contrast of TOC and COD are listed in the table 1."

Jan 1, 2013

By R. V. Ramani, C. B. Manula, A. Owili-Eger

The mine ventilation system consists of the fan, the roadways, and the regulatory devices. Sufficient fresh air must reach each working face in the mines to render harmless noxious, toxic, and respirable pollutants and to provide for the breathing of men. This is achieved by the proper selection of fan and regulatory devices. Because a mining system is dynamic, the mine ventilation system must also be dynamic. In short, mine ventilation engineers are frequently called upon to provide answers to the following questions: 1. Given a mine or the projected plan of a mine, what fan must be selected for the quantities specified in the section? At what point in its characteristic must it be operated? Are any speed changes or changes in blade settings warranted? 2. What should be the regulation in a section to insure cer¬tain desired quantity in that section? How does it affect the overall ventilation system? 3. What are the effects of driving a new shaft? Where should it be located? What size fan should be installed in the shaft? How does this affect the overall ventilation sys¬tem? 4. How much quantity increases can be obtained by cleaning up falls and streamlining roadways and by driving addi¬tional parallel airways? These questions are in no way exhaustive, nor are answers easy. Most of the operational and planning problems discussed above are to a cer¬tain extent solved by ventilation engineers using rules of thumb from experience. Both natural conditions and regulatory requirements have changed so drastically recently that use of scientific methods in ventilation planning and of faster methods in evaluating the plans is a must. Fortunately, computers offer the greatest hope for good

Jan 1, 1975

By D. W. Rudd, D. W. Vose, J. B. Vetrano

In an earlier paper the permeability character of Mo-0.5 pct Ti to hydrogen was described.' It was shown that this alloy is a more effective barrier to the passage of hydrogen than previously studied systems, i.e., copper,2 nickel,3 and several stainless steels.4 The permeability of Hastelloy B to hydrogen was investigated as a material having promising high-temperature structural properties which might have a low permeability to hydrogen. The general theory of permeation has been previously discussed,' and here only a summary of the more important results are given. It is found that except for very thin membranes, at low temperature, permeation of a gas through a metal barrier is determined by the rate of diffusion of the gas through the crystal lattice of the specimen, and that for hydrogen and the common diatomic gases, this passage involves dissociated particles as the diffusing species. The rate of permeation for hydrogen is therefore proportional to the square root of the pressure. It has also been found that the rate of permeation is inversely proportional to the thickness of the barrier. The apparatus used in this investigation was fundamentally the same as that employed in previous studies,' except that several simplifications result in the case of Hastelloy, since oxidation at the temperatures investigated is no longer a problem and welding of the specimen is relatively easy. A cross section of the membrane assembly is shown in Fig. 1. When finished, the assembly is about 5 in. long. The wall thickness is about 6 times the membrane thickness. The membrane (A) can be maintained at

Jan 1, 1963