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By John Clancy, Andrew J. Freyman

"Trends in world coal markets indicate that the next twenty years could be a period of intensive development for British Columbia's coal resource. This paper examines demand projections for metallurgical, thermal and chemical feedstock coals, with particular reference to domestic and Pacific Rim markets. Supply possibilities, from the point of view of British Columbia's competitive position, are explored, with emphasis on the interaction of such factors as capital, labour, port and transportation requirements.The paper concludes with an examination of British Columbia's strategies in light of the foregoing, and comments on the government's role in ensuring that development of the coal resource be attained in a manner consistent with over-all provincial goals and objectives.IntroductionFor the purposes of this paper the Pacific Rim is defined as including, in addition to Canada, the following: Japan, Korea, the People 's Republic of China, Hong Kong, Taiwan, the countries of the Indonesian Archipelago, Australia, New Zealand and the Pacific-bordering countries of South America and Mexico. The United States has been excluded in this definition in order to better illustrate the economic growth potential for British Columbia coal in the Pacific Rim economies.In the past decade, the Pacific Rim economies have grown faster than most other economies in the rest of the world; economic growth rates of 10 per cent were common in the region prior to the 1974 slowdown and the average rate of economic expansion in the mid-1970s has exceeded 6 per cent. Rapid expansion of international trade in the region has been a major stimulus in this process. By 1979, Pacific Rim two-way trade has reached an estimated $550 billion-about 20 per cent of world trade."

Jan 1, 1982

By Amanatidis A

In this paper, the kinetics of iron precipitation as sodium jarosite from aqueous solution is investigated. The determination of the reaction mechanism is attempted based on the experimental data of iron removal as a function of time, without using the characteristics of the precipitate.Experiments at the temperature range from 50° to 95°C were carried out with initial conditions of iron concentration IQ g/L, sodium sulphate concentration 25.44 g/L, sulphuric acid concentration 3.68 g/L, pH = 1.5 and agitation rate 600 rpm. Temperature greatly and positively influences iron precipitation from the solution and this is accompanied by pH decrease. The activation energy was determined using the maximum values of the precipitation rate, which were evaluated by polynomial fitting of the sigmoidal shape experimental curves, and it was found to be 44.37 kcallmole. The determination of the rate-controll ing mechanism was based on some criteria used for the discrimination among the three probable mechanisms of precipitation (diffusion, mononuclear nucleation, polynuclear nucleation). These criteria utilise various funetions of the recovery 'a' of iron precipitated versus time, the most important of which are the chronomals. The results of the kinetic analysis procedure showed that the polynuclear nucleation growth mechanism controls the precipitation of iron as sodium jarosite. This was confirmed by the high value of activation energy, excluding diffusion as the controlling mechanism.

Jan 1, 1993

By Larry G. Twidwell, Corby G. Anderson, Camille M. Fleuriault

"The selective precipitation of iron as ammonium jarosite is a well-established industrial technology in base metals hydrometallurgy. It is a key technology in minimizing iron tenors which would be disruptive to downstream processing. It also provides a more readily filterable iron solid to better facilitate materials handling. This paper elucidates the fundamentals behind industrial iron precipitation. Then, the details of the successful optimization of an industrial ammonium jarosite circuit are presented.HYDROMETALLURGICAL IRON REMOVAL FUNDAMENTALS Iron is the fourth most abundant element in the Earth’s crust (5% by weight) and is often found in complex ores such as sulphide-bearing formations. Iron represents an issue though during leaching, a technology which is widely used for the treatment of this type of ore: •,Iron has the particularity of forming hydroxides when leached under certain conditions. Iron hydroxides form a viscous gel, which is difficult to filter and traps valuable elements such as silver. •,Iron is solubilized along with other metals and interferes with the subsequent extraction steps. As a result, purification of the pregnant leach solutions is required to achieve economical extraction of base metals. In the 1960s, metallurgists developed iron precipitation processes for solution purification (Habashi, 1999). Nowadays, precipitation of iron bearing species, such as goethite, hematite or jarosite, has become one of the most common methods used in the industry to purify leach liquors. To be suitable, the precipitate has to be readily filterable and thus must not be too fine of particle size. Precipitation can take place in autoclaves at medium to high temperatures, under an oxygen or air overpressure (Tourre, 1984, Fleuriault 2016, Fleuriault Anderson Shuey, 2016))."

Jan 1, 2016

CONTENTS [The Nature of Strain Markings in Alpha Brass (paper by J. E. BURKE and C. S. BARRETT, Met. Tech. Feb. 1948. TP 2327). ......................... 2 X Ray Studies of Twinning and Untwinning in Magnesium Alloys (paper by J. B. HESS and R. L. DIETRICH, Met. Tech. Feb. 1948. TP 2328) ................ 11 ]

Jan 1, 1948

By Johnson N. W, Ralston J, Lauder D. W, Smart St C R

The flotation behaviour of the Hilton ore of Mount Isa Mines has been examined in the presence of two collectors (sodium ethyl xanthate (Ex) and sodium diisobutyldithiophosphinate (3418A)) over a range of flotation Eh values and collector additions. Tests were also conducted in the absence of collector to determine the relative contributions of natural and self-induced floatability of the major minerals in the feed. In these tests the influence of metabisulphite on the self-induced floatability of the minerals was also determined. Attention focussed on optimising the selectivity of galena flotation. It is shown that the Hilton ore sample contained lower levels of naturally hydrophobic iron sulphide minerals than are generally contained in the Mount Isa lead-zinc ore. Furthermore, the self-induced floatability of galena was less than that exhibited by the galena in the Mount Isa lead-zinc ore. Sodium metabisulphite (MBS) reduced the self-induced flotation of galena but had no effect on the natural floatability of the iron sulphide minerals.

Jan 1, 1991

The elements of consistent structural de sign models for underground structures are explained. Such models should comprise at least ground properties, excavation and support methods, computational models for analysis, failure hypotheses, and in-situ monitoring. The fundamental characteristics of the interaction between ground and support are investigated. Then, plane strain models for soft ground tun- nelling and design models for rock tunnelling employing stress release at the tunnel face are elaborated. Some numerical evaluations are gi- ven in diagrams, comparing approaches of dif- ferent authors. Comments are presented on nume- rical three-dimensional models (visualized by structural models for mining in rock salt), on the interaction of in-situ monitoring and design, on structural safety for underground structures, and finally on the general develop- ment of structural design models in geo- Techniques.

Jan 1, 1987

By Koppe J. C, Costa J. F C L

This paper compares different results for overburden volume estimation assisted by geoestatistics, particularly using kriging methods. The main goal is to obtain the most reliable digital terrain model for the calculation of the overburden volume. The data was collected on an irregularly spaced grid and interpolated values were calculated to provide a denser, more regular data set before volume estimation. The field work was developed at the Butia-Leste Coal Mine, southern most Brazil, where an accurate survey was done using a total station theodolite with electronic data collector. The study was developed in five main steps: data acquisition, exploratory data analysis, spatial continuity measurements, point and block kriging estimation and verification of the results. Data acquisition was carried out on a 5 x 5 in grid. This dense grid provides an exhaustive data set of the real terrain against which data subsets can be compared for the various interpolation procedures and volume calculation. This provides an interesting insight into the influence of the number of data on the estimation error. Univariate statistics were used to compare each data subset and the exhaustive dataset. Ordinary kriging on the data subsets followed by contouring was carried out using Geoeas and Surfer software respectively. A subroutine written in C provided the link between the files generated in Geoeas and subsequent contouring routines embedded into the Surfer package. Omnidirectional and directional variograms were modelled defining the parameters for kriging estimation using Geoeas. Different variogram models were checked through cross validation prior to kriging. A comparison between the magnitude of the differences in volumes calculated with the different DTMs was attained. These final result indicates the sensitivity of the volume obtained to the number of data points. As the number of data points increases the estimation error decreases, but at some point there is no significant decrease in the final volume with the collection of additional data.

Jan 1, 1995

By Panlop Huttagosol

The use of computer models to design ultimate pit limit of an open pit mine during its feasibility study has become an emphasized procedure in mining. It is a normal practice in open pit mine design to generate the most profitable final pit limit. The limitations of designing this optimal pit limit have been the requirement of significant computing efforts as well as the use of complicated operations research techniques. In an attempt to describe a computer method that has an easy conceptualization and is able to provide a precise and desirable solution, a new technique is developed. The ultimate pit limit problem is formulated as a large scale transportation problem. The formulation is based on the use of a three dimensional block model to represent an ore body and surrounding materials. The solution technique is developed through solving the dual system of the formulated problem by using the adapted simplex algorithm of linear programming. The implementation on given case studies demonstrates that the new method is capable of providing an optimum pit value. The computing effort required by the algorithm is still the main constraint in solving a large scale problem. The technique provides open pit mine planners with an alternative tool in using a commercial linear programming software which is capable of solving a general transportation problem. The selected software must be able to handle a large scale problem, and it needs an additional effort td formulate the problem and transform a result into the ultimate pit limit solution.

Jan 1, 1992

President Zakotnik opened the final session of the Institute at 9:30 a.m. Kenneth R. Herrmann of the Resolutions Committee presented the following resolutions to the group for their approval: RESOLVED: That the members of the Rocky Mountain Coal Mining Institute, in convention assembled, hereby ratify and confirm all official actions of the officers, the executive committee and other committees of the Institute between July 4, 1962, and the present time.

Jan 1, 1963

By John D. Sullivan, Edwin J. Rogers, Chester R. Austin

THE problem of making a building unit combining the necessary physical and mechanical properties and good thermal insulation has been foremost in the minds of architects and ceramic and construction engineers for many years. This paper presents the results of studies on thermally expanding shales or clays to produce light-weight cellular products suitable for making building units. An expanded clay block suitable for building purposes should be large enough so that substantial savings may be effected in labor costs in laying the wall. The permeability should be low and it should have sufficiently good "dry-wall" characteristics to permit exposing the exterior surface to the elements, and to permit plastering directly the inside wall surface. The thermal conductivity should be low and the mechanical properties should be adequate. Obviously, a unit possessing satisfactory qualities for constructing an outside wall would be satisfactory for interior walls and for back-up purposes. The results of studies on bloating various shales or clays† and the properties of the expanded products are reported. In another paper1 basic factors involved in bloating of clays are discussed. Manufacturers of ceramic products, particularly structural clay, may encounter bloating of the ware during burning, and precautions must be followed to avoid this phenomenon. About 1927 the C. F. Burgess Laboratories, Madison, Wis., while carrying on an investigation for the American Face Brick Research Corporation, conceived the idea of intentionally bloating clay while holding it in a restrained condition, with the hope of producing a unitary cellular mass. Work was carried on until about 1931, when studies were terminated because of business conditions. These studies were continued later by The Western Brick Co., Danville, Ill., which developed a process of "inwardly expansive bloating." The major purpose of the latter investigation was to produce back-up tile to compete with concrete blocks made from Haydite or cinder aggregate. Haydite is a light-weight aggregate formed by heating certain clays or shales rapidly in a rotary kiln. While the investigations at the C. F. Burgess Laboratories or at Western Brick Co. were not carried far enough to lead to the commercial production of material for the construction of walls, particularly outside walls, they showed that certain clays could be thermally expanded and that it was possible to produce a material of low permeability with a large percentage of the total voids or cells closed. Commencing in 1939, the Ozark Chemical Co. sponsored a research program at Battelle Memorial Institute for the purpose of determining whether it is technically feasible to make thermally expanded building units, and specifically to get answers to the following questions:

Jan 1, 1942

By G. M. Wilemon

The U.S. Bureau of Mines has conducted investigations on extracting phosphate values from wastes generated during the mining and beneficiation of phosphate matrix. These wastes may contain up to one third of the phosphate originally present in untreated ore. Samples of wastes were air-dried and leached using 93 pct sulfuric acid in the presence of methanol. Evidence for the formation of a calcium sulfate hemihydrate coating that hinders complete dissolution of phosphate is presented. Solid-liquid separations were enhanced when flocculation was effected using poly(ethylene oxide) (PEO) in conjunction with hydroxypropyl cellulose (HPC) or hydroxyethyl cellulose (HEC. A conceptual flowsheet for a proposed process using an acid-alcohol leaching technique is presented.

Jan 1, 1990

By Marvin J. Udy

THE preparation of this paper is in response to many requests for in-formation on the mining and smelting developments which have been carried on for the past three years or more by the Chromium Mining and Smelting Corporation of Canada. By way of introduction, the following paragraphs, relating to the early history and present status of the chrome-mining industry in the United States, are of interest. They are quoted from Bulletin No. 76 of the California State Mining Bureau, published in August, 1918: 'Chromium was discovered about 1797 by a French chemist, Louis Nicolaus Vauquelin, in ore from Siberia. From that time until 1827, the Urals, in the region of Ekaterinburg, supplied the chromium used in . Europe. In the summer of 1827, as the historian advises us, Isaac Tyson, Jr., saw in a Baltimore market-place a cart containing a cider barrel, which was held from rolling about by some heavy black stones. He had made a study of such stones at the first-known American locality, the Bare hills near his father's home, six miles from Baltimore, and he recognized the black stones as chromite. On inquiry, he found the chromite came from the Reed farm in Harford county, 27 miles northeast of Baltimore. At this time, Tyson was one of the very few men in the country who knew the value of chromite, and in the next few years he took full advantage of this knowledge. He immediately bought the Reed farm. He found about 30 tons of float-ore on the surface, but there was no outcrop of ore in place. Never-theless, he sank a shaft, and at a depth of eight feet struck an ore-pocket which proved to be 80 ft. long, 25 ft. wide, and 8 ft. in maximum thickness. His next discovery was of placer chromite in the sands in the beds of brooks on an estate called Soldiers' Delight, 16 miles northwest of Baltimore. Thus far, Tyson's observations had shown him that chromite occurred apparently only in serpentine areas. His explorations were now leading him farther afield. In 1828, he found on the Wood Farm, in Lancaster county, Pennsylvania, a deposit of float chromite which led him to lease the ore-right of the farm, which he finally purChased in 1832. Here he developed the famous Wood mine, the largest single producer of chromite in the world.

Jan 1, 1938

By Frederic Becket

IN a recent article,1 which described the softening effect of columbium in plain high-chromium steels, the authors stated that their investi-gations had shown columbium to be also a particularly valuable inhibitor of intergranular corrosion in steels of the 18 per cent chromium, 8 per cent nickel type. It is the purpose of the present paper to record some of the results obtained through the introduction of columbium to the austenitic chromium-nickel steels. The damaging effects of this type of corrosion have become so widely known as to restrict considerably the applications of the steels under consideration, and therefore there is little question of the importance of the goal to be attained. Numerous contributions concerning the susceptibility of the aus-tenitic chromium-nickel steels to intergranular corrosion have appeared during the past few years, and among others who have dealt construc-tively with the subject are such well-known authors as Strauss and Houdremont of Germany, Hatfield of England, and Bain in the United States. Different theories have been propounded as to the cause of intergranular corrosion, and various remedial measures have been proposed, the majority of which involve the use of addition agents. Titanium is the addition agent at present most generally employed, as suggested by Houdremont and modified as described by Bain, Aborn and Rutherford.2 Little has been published on the effects of holding these steels for long periods at the relatively lower temperatures in the presence of

Jan 1, 1934

By M. Baeyertz

SINCE 1915 many papers and books have covered industrial applications of X-rays from various angles. Two of the more recent are a paper by Fink and Archer1, which describes in detail the technique of radiography, and a paper by Clark2, which embraces the whole field of X-ray metallography. This paper, therefore, is confined to work of the X-ray Laboratory of the Western Electric Co., which naturally divides into two categories: radiography and diffraction patterns of various types.

Jan 1, 1930

By C. E. Baltzer

This paper highlights the position of coal supply in regard to the requirements for electric-utility operations. The text and the appended tables outline the trend of thermal power development and fuel use in the electric-utility industry. Mention is made of several argumentative factors influencing the use of coal in relation to competitive oil and gas, and of the importance attached to developing a realistic understanding of the respective problems faced by the supplier and consumer of coal. * * * TREND OF" THERMAL POWER DEVELOPMENT T HE RATE OF ADVANCE in thermal power has been significant during recent years, particularly in the Atlantic Provinces, the Prairie Provinces, Ontario, and British Columbia. While dependence on thermal power in Quebec and the Northern Territories is less than in the remainder of Canada, these regions also eventually will have need for increased amounts of such power.

Jan 1, 1961

By Francis F. Lucas

A microscope objective of given numerical aperture, when used with light of given wave length, has some fixed limit of resolution. This may be expressed as potential resolving ability—the ability to resolve is inherent in the lens but whether this limit is achieved in practice is quite another matter. Nearly 50 years ago Abbe evolved theoretical considerations which indicated that the ability of a lens to resolve detail is directly proportional to twice the numerical aperture of the objective and inversely proportional to the wave length of the light used. It is true, unquestionably, that as the numerical aperture of the objective is increased the potential resolving ability of the lens is increased and likewise when the wave length of the light used is decreased, the degree of resolution is increased. Whether Abbe's formula expresses the exact relationship is not a matter of great concern. It suffices to know that to improve resolution, other things being equal, two avenues of approach are available. Either the numerical aperture of the objective may be increased or the wave length of the light decreased. With the apochromatic system it is possible to employ successfully wave lengths from 400 to 500 uu and still secure reasonably short exposures. The present limit for numerical aperture is 1.40 N. A. although objectives of 1.60 N. A. are now an experimental possibility for metallurgical work. Thus certain well defined limits are set for those who work within the range of the visible spectrum. In order to take advantage of the increase in resolving power which accompanies a decrease in the wave length of light employed, Dr. A. Kohler and Dr. M. Von Rohr of the Zeiss Scientific Staff developed the "monochromats." These are quartz objectives corrected for the single wave length 275 uu which lies in the ultra-violet region of the spectrum. They also developed a series of quartz oculars and a complete photo-micrographic equipment with which to use the quartz optics. Quartz must be used for the optical parts because glass absorbs ultra-violet light almost completely. Thus there was made available about 20 years

Jan 1, 1926

By Lucien Eaton

This paper describing the mining practices at Mine No. 2 of the Marquette Range, Michigan is one of a series being prepared by the Bureau of Mines on mining practices, methods, and costs in the various minim; districts of the United States. The publication, of this information should be of interest to the industry at large and the exchange of ideas thereby made possible should be of economic value to operators in all harts of the country. ACKNOWLEDGMENTS The author is indebted to the superintendent, engineer, and mining captain of the property discussed in this paper for much of the information presented. The geological classification is taken from publications of the U. S. Geological purvey.

Jan 1, 1929

By Luis Remy Valdivieso

Las minas de Marcona, principales productores de mineral de fierro del Perú, están ubicadas a 400 km, en línea recta al Sur-Este de Lima. Debido a la geología del terreno, los minerales eran virtualmente desconocidos hasta 1952. Ya, con la explotación geológica completa efectuada durante los úitimos diez años, se ha probado que la oxidación y el intemperismo han causado alteración en el tipo de minerales presentes. Asimismo, la gran mayoría de los minerales tiene un alto contenido de azufre que los hacen económicos. En ese sentido, el presente texto señala la comercialización de los minerales en Marcona, donde las pruebas metalúrgicas demostraron que tales minerales pueden ser sometidos a un tratamiento que los convierte en productos comerciales. Por ello, ante el requerimiento más exigente de los compradores referido a especificaciones físicas y químicas del mineral, la Marcona Mining Company decidió instalar una planta de beneficio capaz de impartir a los minerales provenientes de las minas que explota el más alto grado de pureza conocido actualmente. Así, la planta de San Nicolás produce cuatro tipos distintos de mineral de fierro para uso en altos hornos o bien en hornos de sinter, y como consecuencia, se aseguró la vida al distrito minero de Marcona.

Jan 1, 1965

By P. V. Faragher

A METAL or alloy finds its place in commerce in proportion to its ability to serve certain purposes better and more economically than other materials. While there is some overlapping of the fields of application of the various metals under discussion in this symposium, each one has its uses for which it is especially adapted. While aluminum is the most recent of the metals to enter the field, the development of the industry has been based on its peculiar properties, by virtue of which new uses for non-ferrous metals have been created. There has been substitution of this new metal for other members of the group but there has been a far greater development in entirely new fields. In common with the other non-ferrous metals, aluminum is resistant to atmospheric corrosion. It also withstands the action of many of the common chemical reagents, strongly alkaline substances being the notable exceptions. The outstanding properties on which the application of aluminum is based are its low specific gravity and its ease of fabrication into the forms in which it is used. It is noteworthy that this property of specific lightness is retained in all the commercial aluminum-base alloys. This statement does not apply to aluminum bronze; this is more properly a copper-base alloy, since aluminum enters into its composition to the extent of only about 10 per cent. None of the commercial casting alloys of aluminum has a density exceeding that of the parent metal by more than about 10 per cent., and some are actually lighter. In the so-called "strong alloys" of aluminum in which strengths comparable to that of mild steel are developed by heat treatment, the greatest increase in density is only slightly more than 3 per cent., and one of these, also, is lighter than aluminum. This property of lightness combined with the desirable mechanical properties of the alloys, makes aluminum especially suited for parts of moving assemblies where saving in power, as well as a decrease in stresses resulting from inertia and vibration, are of importance.

Jan 1, 1928

By J. H. Weber

This Bureau of Mines publication describes the hardware system and software package for the semiautomatic acquisition and automatic processing of high-resolution mass spectrographic plates. The semiautomatic data acquisition allows a tenfold saving of time compared with manual data acquisition. Automatic processing of the high-resolution data to yield exact masses, intensity, and the corresponding empirical formulas is accomplished by efficient programming on a small, inexpensive, programmable calculator system.

Jan 1, 1974