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By Jehan Rondot

Des quartzites très pars ont été dêcouverts au cours de la cartographie de la region du lac des Martres, étape de l'étude géologique de la region de Charlevoix. On distingue quatre groupes métasédimentaires, tons con tenant des niveaux de quartzite dans an moins deux domaines géologiques différents, c'est à l'ouest, clans le domaine gneisso-charnockitique que se situent les quartzites du groupe des Martres. Quartzite et gneiss à grenat et sillimanite, en banes épais, constituent la formation de La Galette. A Pest, dans un environnement gneisso-granitique, les deux groupes métasédimentaires de Saint-Siméon, et de La Malbaie comprennent, par contraste, des bancs pen épais et de compositions variées. Les niveaux de quartzite dépassent rarement 50 m d'épaisseur. L'autre groupe metasédimentaire, celui de Saint-Tite des Caps, recoupé de nombreuses intrusions charnockitiques et granitiques, ne possède que de minces niveaux de quartzite. La pureté et la grande épaisseur des quartzites de La Galette suppose une histoire complexe qui se termine par des depots continentaux de climat aride, par opposition aux depots marins des autres groupes. D'autre part, la presence de ces quartzites an sein de roches Presque anhy¬dres et de haute temperature que sont les charnockites leur confère des caractéristiques de fusion sans decrepitation. Parmi la multitude de depots de quartzite qui existe clans le monde, peu sont de qualité supérieure. Or, de par sa composition chimique, le quartzite de La Galette se compare avantageusement à ceux des meilleurs gisements des Etats-Unis, de l'Europe de l'Ouest et de l'Afrique du Sud. D'accès facile pour l'exploitation, les gisements ne sont qu'à une trentaine de milles de Baie Saint-Paul ou de La Malbaie, sur le Saint-Laurent. L'utilisation en metallurgic prévue pour le quartzite de La Galette comprend la production de silicium, de ferro¬silicium et d'autres alliages de silicium. La composition du quartzite est en outre appropriée pour la production de carbure de silicium et de silicate de sodium. Les fines peu¬vent être utilisées pour la fabrication du verre et comme matière de charge.

Jan 1, 1977

By Peter F. Steidl

As part of the Bureau of Mines methane control program, the Upper Free- port coalbed was studied in Fayette County, Pa., where this coalbed lies about 650 feet below the Pittsburgh coalbed and contains the largest remaining reserves of any coalbed in the county. Coal and overburden isopachs, structure and joint pattern maps, and a fence diagram were prepared using data from gas and oil exploration logs and coal outcrops. These maps will aid in determining the need and/or feasibility of degasifying the Upper Freeport coalbed in the study area. Much of the coalbed in this area is under 600 to 1,400 feet of overburden. By correlation with data from the Pittsburgh coalbed, the gas content at depths of this order is estimated to be between 140 to 300 cf/ton of coal, for a total of 190 to 400 billion cubic feet of methane in this coalbed in Fayette County.

Jan 1, 1977

By J. P. Morgan, D. B. Stewart

"AbstractLoad-haul-dump machines equipped with. a torque converter and hydraulic pumps have been field tested by means of an engine monitoring instrumentation package. It was found that owing to parasitic losses in the ancillaries and drivetrain, maximum available useable pourer may peak at less than full engine speed. Simple reduction of engine speed may save 15 to 25 percent on fuel consumption, with no significant loss of available power. On some machines, speed reduction will require modification of the torque converter . The cost of this modification, when necessary , would be offset by reductions in exhaust emissions, ventilation requirements, fuel consumption , heat, noise and hydraulic system maintenance, and by increased life of rotating components and filters and machine availability.IntroductionTHE CANADIAN EXPLOSIVES ATMOSPHERES LABORATORY, in conjunction with Deutz Canada Limited, has designed, constructed and field tested a portable instrumentation package. This package monitors diesel engine performance in underground mining machinery by continuously recording engine speed and volumetric fuel delivery. During tests designed to determine the engine load and speed conditions for the various segments which constitute actual underground operation of a Deutz F6L 714-powered 4-yard load-haul-dump machine, it was discovered that an unexpectedly large percentage of the engine power was required to overcome the ancillaries and drivetrain drag (1). That this large component of engine power is functionally related to engine speed rather than the operator's needs was verified by repeat tests of the used 4-yard machine and by testing of a new 5-yard machine powered by a Deutz F 8L 714."

Jan 1, 1977

By James J. Scott

Eleven workshops were held in various locations throughout the country in an attempt to reach the many diverse groups working in various mineral commodity areas and special ties. These meetings were held between March 1, 1974 and June 25, 1975. They were held under the auspices of the Bureau of Mines Contract to the University of Missouri-Rolla which was designed to help define Bureau research and development priorities. At each workshop a summary of current Bureau research and development was presented and the attendees were asked to present their ideas on what Research and Development programs should be undertaken to meet their needs locally. Participants included representatives of federal and state agencies, educational institutions, mining companies, equipment companies and other interested parties. The workshops covered under this report include lead mining in Missouri, limestone mining, coal mining both surface and underground in the midwest and in the Rocky Mountain area, iron mining in Minnesota, two top management meetings on institutional problems and, finally, a special two-day meeting on roof control.

Jan 1, 1977

By John C. Edwards

A two-dimensional, time-dependent, mathematical model has been developed that describes fire spread along the walls of a ventilated duct. The model is based on the assumption that the leading edge of the fire zone propagating along the wall surface coincides with the isotherm for the fuel ignition temperature. The model includes gas-phase energy transport via radiation and forced convection inside the duct and solid-phase energy transport by conduction into the fuel lining. Product gases emitted from the fire zone are assumed to mix uniformly with the ventilation gas to produce an optically dense gas mixture at the combustion temperature that enters the preheat region. Numerical solutions of the model equations for a coal-lined duct (simulated coal mine entry) have been used to investigate the effects of tube radius, air velocity, combustion temperature, and optical density of the soot-laden gas upon the terminal fire spread rate.

Jan 1, 1977

The geographical and geological situations of the two mineral sand deposits currently being mined by Western Titanium Limited and the mining methods in use are briefly described. Production scheduling involving the ability to vary the proportions of the major minerals produced, together with maintaining a constant feed grade to the wet concentrator has been assuming greater importance to the company in recent years as the relative value of these minerals, due mainly to technological advances and environmental considerations, is subject to significant and rapid change. Manual calculation, even using a programmable calculator, became a trade-off between man hours and data usage. Schedules were updated infrequently and only a fraction of the avail- able data was used. In July 1975 a Data General NOVA 2/10 minicomputer with a 24K word core and three cassette drives was purchased. A suite of programmes was developed using BASIC to assist in production scheduling and these were opera- tional early in 1976.

Jan 1, 1977

By B. M. Bench

This Bureau of Mines report describes photo lineaments obtained from stereoscopic examination of vertical aerial photographs and by the Ronchi grating study of aerial photoindex sheets. The photolineaments are compared with the trends of oriented fracture systems procured by measuring the compass direction of joints in bedrock. The relative reliability of the methods is shown, and the results are presented in graphical, tabular, and written form. Analyses of field measurements of strikes of bedrock joints in the project area indicate for the most part two intersecting sets of major joints oriented N 76° W -N 15° E, and N 57° W -N 27° E. The analyses of lineaments determined by stereoscopic examination of aerial photographs show dominant trends of lineament zones of weakness to be an average of N 65° W -N 20° E. Analysis of lineaments found by Ronchi grid viewing of aerial photoindex sheets indicate dominant trends of N 70° W -N 27° E. The three methods give similar findings and verify the work of previous authors. The Ronchi grid method is a useful guide, but it cannot be substituted for the two more painstaking methods.

Jan 1, 1977

By Richard E. Hucko

The bureau of Mines conducted a laboratory scale investigation of the process of selective flocculation with the objective of developing a method to effect separations on suspensions consisting predominately of ultra-fine-size (minus 400-mesh) particles of coal and refuse. Selective flocculation of coal from coal-refuse slurries could be achieved with a wide variety of reagents. Typically as much as 15 to 20 weight-percent of high-ash solids (70 to 80 percent ash) could be retained in suspension. The flocculated sediment remained a high-ash product, however, and would require further treatment to be regarded as clean coal. No combination of reagents and conditions led to selective flocculation of the refuse component. The dispersing agent was found to be the critical factor; dosages of 3 to 8 lb/ton2 were necessary to stabilize the suspension for subsequent selective flocculation. In addition, most of the dispersants that worked were most effective at substantially elevated pH (11 or so). It was concluded that this process would be prohibitively expensive and, because of yield and quality constraints, it would be of questionable utility in today's coal preparation industry.

Jan 1, 1977

By Neall. George M.

No method of roof control yet devised has proven to be universally acceptable for the wide range of strata conditions experienced in U.S. coal mines. However, a relatively new innovation, the roof truss, has proven itself capable of preventing roof failures which both conventional and resin bolting could not. Presently, the economics of roof trusses are not favorable when compared to bolting due primarily to drilling and installation procedures, but this is expected to change with improved truss and equipment designs. To realize the full potential of this new method of roof control, design criteria are needed which can optimize the effect of the truss for varying strata conditions. A review of the literature reveals that some work has been conducted on the roof truss. 1 Gambrell and Haynes (1970) showed that the roof truss is superior to angled roofbolts installed through a header. Sheorey, Verma, and singh2 (1973) used statics to prove that the optimum angle of inclination should be greater than 450? However, to date, no systematic attempt has been made to establish design criteria. In this report, the problem was approached in three ways. First, model studies were performed to determine general trends of truss support as a function of a number of variables. This provided a better understanding of the support mechanism involved. Secondly, beam theory was employed to calculate the actual support capacity of a truss, realizing the many simplifications, assumptions, and shortcomings of this approach to such a complicated problem. Last, field testing will be utilized to test the hypotheses previously developed and provide hard data to further synthesize roof truss design criteria. Field testing has recently commenced and should be complete before mid 1977.

Jan 1, 1977

By J. G. Cullain

Inco Limited is an integrated mining, smelting, refining and manufacturing company with operations located worldwide. The Ontario Division operations consist of 13 mines and 10 processing facilities located in Sudbury, Port Colborne and Shebandowan. The scope of our utilization of energy in the Ontario Division in 1976 included in excess of 2.2 billion kilowatt hours of electric power, 12 billion cubic feet of natural gas, 60 million Imperial gallons of residual oil and smaller quantities of other fuels. In addition to the primary energy consumption, waste-heat energy is recovered in various operations throughout the Division, thereby reducing our primary energy requirements. Total expenditures for primary energy alone in 1976 exceeded 60 million dollars. Energy management studies were initiated by Inco's Utilities Department in late 1972, and resulted initially in a program of electric power cost reduction. This program produced significant results by improving the use of the water available for our hydraulic generation facilities and by a comprehensive peak reduction program. Our experience showed that a program of peak power control creates an awareness of both peak and energy costs, and thereby encourages a general reduction in the electric energy consumption as well as lowering the peak demand. Energy management is a continuing program at Inco and, recently, a formal energy management policy and program was instituted. Energy management committees were formed in each plant or mine area to identify the major areas for energy; consumption, thereby isolating areas with large potential energy losses, and determining immediate action which will improve the energy efficiency or reduce the energy waste within their respective areas. A decentralized program with good cross-communication between all committees was felt to be the best method of providing an on-going effective energy management program. In the future, the projections of dwindling fossil-fuel supplies in Canada and the resultant spiralling energy costs will further emphasize the need of sound energy management practices for all Canadian industry.

Jan 1, 1977

By I. L. Nichols, D. C. Seidel, D. E. Traut

A fluidized countercurrent ion-exchange system was developed, operated, and evaluated by the Bureau of Mines. The system consisted of integrated multiple-compartment absorption and elution columns in which the solution flows are continuous except for short periods when resin increments are withdrawn. The exchange of uranyl sulfate between a simulated acid leach uranium solution and a strong-base, ion-exchange resin together with the subsequent elution with an acidified sodium chloride solution was studied. The effects of the number of sections, section heights, amount of resin withdrawal, and solution flow rates were investigated. Also examined were the kinetic and equilibrium relationships for the absorption step. The experimental data indicate a strong interdependence between variables. Solution retention time appears to be a major limiting variable. The column was efficient over a range of conditions, but close control was needed for optimum operation.

Jan 1, 1977

By Michael Rieber

This study is an extension of our previous work in the area of coal transportation Its subject is the comparative costing of competing transport erodes. A wide range of costs and aspects of costs are dealt with in terms of engineering - economic analyses of the cost of the components which make up the facility and operating system descriptions of each coal transport mode. The cost comparisons, though analyzed, are not meant to be statements of policy but, rather, an input to decision making. The technical material presented in the succeeding volumes, alone with the earlier work cited above, forms the basis for the analyses. This material may also broaden the general understanding of coal transportation issues and problems. The project is divided into two main sections: (1) lone distance coal transport and (2) gathering and distribution systems. Within each section economic and technological comparisons are made of the available modes. These are used as the basis for comparisons among the modes. Inter-modal compatibility is studied with respect to both mixed trunk line shipment anti with respect to feeder to trunk line and trunk line to distribution systems. The engineering and technological data form the bases for the costing and economic analyses.

Jan 1, 1977

By Jerry R. Johanson

The practical application of rolling theory to the design of roll presses is reviewed along with aspects of plant operations which must be considered to produce the required product economically. Appropriate parameters to scale up from laboratory tests to full- scale press operation and improvements possible in existing operations are discussed.

Jan 1, 1977

By Bratt G. C, Horsham T. R, Langlois D. R

Mercury is precipitated from weakly acidic sulphuric acid plant waste liquor at the Risdon Works of the Electrolytic Zinc Company of Australasia Limited. Factors determining the choice of process and reagent, as well as details of process development including scale- up, and the time scale of implementation are outlined. The plant is designed for a maximum flow of 120 m3/h.of liquor containing mercury and saturated with sulphur dioxide. Mercury is precipitated by fluidised beds of aluminium pellets contained in lead columns. Liquor is then clarified with plate and frame presses. Experimental work on the mercury precip- itation reaction was conducted in three phases involving a scale-up of 100 times in equipment size. Extensive pilot filtration work was carried out on a 1 m2 press. Scale-up of 120 times was required for specification of plant filters. The basis of scale-up is outlined.

Jan 1, 1977

By A. H. Rhoades, D. T. King, R. J. Gray

Tests and methods of detecting oxidized coal are studied. Particular emphasis is placed on the microscopically discernible changes that accompany the chemical and physical changes affecting the technological properties of coal during oxidation. Coal samples were used from the low-volatile Pocahontas No. 3 Seam, McDowell County, W.V., and from the high-volatile Cedar Grove Seam, Mingo County, W.V. Tests conducted include: carbonization, free-swelling index, phase inversion, froth flotation, Gieseler plasticity, oxygen by difference and by neutron activation, volatile matter, pH of coal slurries, alkali solubility, and electrostatic charge.

Jan 1, 1977

By Daniel E. Sullivan

The recession of 1974 continued into 1975. Real gross national product (GNP), measured in 1972 dollars, declined significantly in the first quarter of 1975 but rose slightly in the second and increased sharply in the third quarter. Unemployment peaked during the second quarter and then declined slowly for the balance of the year. The inflation rate declined owing to reduced demand and smaller-than-1974 increases in energy and food prices early in the year. Recovery was clearly evident by yearend, though un-employment and inflation remained at high levels. Total output as measured by the GNP in current dollars rose 6.5% in 1975. Real GNP declined 2.0%, and inflation, as measured by the implicit price deflator, increased 8.7%. Real gross private domestic investment for residential structures declined 18.1% in 1975, which was a smaller rate of decrease than the 27% decline in 1974. Real State and local Government purchases increased 2.4%, and real personal consumption expenditures for services rose 1. 7 %. The Federal Reserve Board (FRB) index of industrial production declined 9.7%.

Jan 1, 1977

The problems encountered with the introduction and use of Isanol underground are described. Significant direct as well as indirect savings have resulted from the use of Isanol. Field studies have shown that the concentration of common gases released during detonation is considerably lower than with conventional nitro-compound type of explosives.

Jan 1, 1977

The principles and utility of in-situ coal gasification are discussed, and a first field test conducted by the Alberta Research Council in 1976 near Forestburg, Alberta, is described. The test was carried out in a 12-ft subbituminous coal seam under 60 feet of cover. Within this seam, a 30 by 60-foot block , containing approximately 650 tons of coal, was delineated by four injection/production holes which were oriented to take advantage of the natural fracture system in the coal. Linkage between holes was established by reverse combustion and gasification was accomplished by injecting air into the ignited coal. No steam was injected but operating pressures were adjusted to utilize formation waters for partial carbon -steam gasification. The coal gasification runs lasted six weeks and gasified an estimated 900 tons of coal ,' during sustained periods of gasification, a fuel gas with heating values of between 110 and 150 Btu/scf was obtained. Plans are now being developed for excavating the test site and inspecting the subsurface cavities created by gasification.

Jan 1, 1977

By R. L. Morse

The thermodynamic program is similar to previous mine ventilation programs but has been expanded to consider the compressibility of air. The thermodynamic program does consider: 1) air density variations, 2) humidity changes, 3) intake, exhaust, and underground fans, 4) heat transfer between rock and air, 5) refrigeration of heating plants, both surface and underground, and 6) heat generated by equipment, both diesel and electric. 110st of the compressibility factors are handled in the branch calculations. The field survey necessary to supply-data for this program is quite similar to the basic base and leap-frog pair of stations method used with most incompressible mine ventilation programs. The thermodynamic program is a complete package of ventilation network analysis which can provide mine management with good operational control and planning of mine ventilation systems.

Jan 1, 1977

By Marvin P. Barnes

The Sacaton open pit copper mine has recently been placed into production. Some problems have been encountered in maintaining grade control due to differences between early block estimates and actual production grade. A study was made using three methods for computing grade for 50' x 50' x 40' size blocks from exploration and development drill holes; 1) The polygonal method, 2) The inverse distance squared method, and 3) The geostatistical kriging method. The results of each were compared against a control block file created by using the assay results of all blast holes drilled in the ore over three benches of the new pit. Results indicate that the kriging technique gave better estimates for grade of individual blocks than did the other two methods for this particular deposit.

Jan 1, 1977