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By W. E. C. Eustis

In September last I had my attention called by Mr. R. G. Leckie to a deposit of nickel in the township of Orford, province of Quebec. In many ways it has proved to be a subject of great interest. As this ore is, as far as I can learn, entirely new in mineralogy and metallurgy, it has seemed to me that it would be a matter of interest to the Institute to have laid before it, in a short paper, the peculiarities I have met with in studying it. This deposit of nickel was first described by Dr. T. Sterry Hunt, our President, in the Geology of Canada, 1863, p. 738, in the follow ing terms: " The general diffusion of nickel throughout the magnesian rocks of the Quebec group has been already noticed. It has, however, never been met with in any considerable quantities in these rocks, although workable deposits of its ores may reasonably be looked for

Jan 1, 1879

By Guy R. Johnson

Like many other similar plants the ore-washer of the Longdale Iron Company has been a growth of years. In its principal features there is probably nothing new, as the type is that of the well-known " log-washer." Some of its minor details may, however, be of interest to those members who have to deal with the washing of large quantities of brown iron-ores, the principal gangue of which is clay. * Until 1883, the ore at Longdale, being of unusual purity, needed no washing, and was charged to the furnaces as it came from the mines—both lump and fine—the only attempt at cleaning being the' picking over a screen of 1½-inch iron bars, 3½ inches from center to center, set in the top of the bins through which the cars for the furnaces were loaded." In 1883 it was no longer possible to win the ore by open cuts, and regular underground work became necessary. It was very

Jan 1, 1895

By Joseph Cervik

INTRODUCTION Common methods of controlling gob gas in U.S. mines are by means of ventilation of gob areas and gas drainage through surface boreholes. Costs of drilling surface gob holes increase as deeper coal- beds are mined. Where gob holes cannot be drilled because of topography, ventilation is the only means of control. Even then, sufficient air may not be available to dilute methane in the bleeder entries to acceptable levels. Thus, new methods of gob gas control need to be developed that are independent of surface topography, and of the mine ventilation system, and less costly than present systems. Except for slight variations in procedures and equipment, Great Britain, West Germany, France, Belguim, Poland, and Czechoslovakia use a common methane control method that is different from the system generally used in the United States. This Bureau of Mines paper reviews European mining methods, mining conditions, and methane control technology and discusses their applicability to U.S. mines.

Jan 1, 1981

By Robert W. Thompson, Darry A. Ferguson

In August, 1977 the United States Congress passed Public Law 95-87 which has been commonly referred to as the Surface Mining Control and Reclamation Act (or SMCRA). This title is somewhat misleading in that the act creates as many regulatory requirements for underground coal mines as for surface coal mines. How- ever, this paper will concentrate on the effects of SMCRA on designs and stability for various activities of surface coal mines, specifically those concerning "Disposal of Excess Spoil". In the past, the objective of most laws and regulations applicable to the mining industry has been to achieve goals of safety or environmental concerns for all types of mining. However, SMCRA is unique in that it sought to regulate-all-activities of coal mining from initial data gathering, exploration, mine design and facilities design to reclamation activities and design. More specific to the stability of the activities of surface coal mining, special criteria for design and construction performance standards have been promulgated for the construction and maintenance of roads, dams and embankments, coal processing waste, ex- cess spoil piles, backfilled reclamation and pit slides. The criteria for design for the previously mentioned facilities has been enumerated by regulations and in many ways restrict the use of site specific design parameters. The restrictions imposed by regulations significantly inhibit the engineer's ability to develop the best practical and economical design and in some cases may re-

Jan 1, 1983

By Guang Ping Cui

In this paper the imminent relationship between rock burst and its phenomenon with normal rock pressure and its appearance, as well as the factors of one changing into another have been analyzed. Based on this, the necessary and sufficient appearing factors of rock bursts have been put forward, and the term ''burst pressure" has been defined. According to the statistics data of tremendous rock bursts which appear in collieries in Hunan Province, the features of high frequency, great strength and shallow depth of the beginning burst have been found. There are some special structures in the coal seams, which are closely related with the burst phenomenon. A hypothesis of "star structure" has been suggested for the appearing mechanism of bursts. Inside and around this star structure the distribution rule of burst pressure and rock strength has been researched depending upon the theory of the limited stress field. A new description of the appearing causes of bursts has been raised.

Jan 1, 1984

By William M. Kester

INTRODUCTION The Coal Research Bureau of the School of Mines at West Virginia University is presently conducting laboratory-scale tests to determine the technical feasibility of beneficiating pulverized coal and coal fines with high-intensity electromagnetic fields. Interest in magnetic processes for cleaning fine coals was stimulated by results obtained by Yurovsky, et a1 in 1958.1 This work, while not new in concept,2,3 indicated that pulverized coal which had been thermally treated in a rotary drum in the presence of superheated steam and air underwent thermo- chemical reactions. Films of the ferromagnetic minerals magnetite (Fe2O3), hematite (Fe3O4), and pyrrhotite (FeS[3]) were reported to be formed on the surfaces of the pyrite grains associated with fine coal during the foregoing treatment at temperatures ranging from 120 to 360°C. After thermal treatment the coal was magnetically separated in an experimental magnetic device having a field strength of 10,000 oersteds.

Jan 5, 1965

By K. J. Kutz, F. A. Nice

Drilling of the second shaft at Texas Gulf Sulphur Co.'s Cane Creek potash operation southwest of Moab, Utah, is perhaps the largest undertaking ever made by private industry in the field of rotary shaft drilling. The new shaft, known as No. 2, is located within the plant area, about 400 ft northeast of the No. 1 shaft. This location within the pillar of the first shaft allowed utilization of a great deal of in- formation gained prior to and during sinking of the original No. 1 shaft, a conventionally sunk 22-ft diam shaft 2789 ft deep. The No. 2 shaft will be used for auxiliary transportation of men and supplies, and is steel lined with a 48-in. ID casing. The top 825 ft of the shaft is in predominantly red sandstone with interbedded shales. From 825 ft to 2800 ft, which is the top of the salt beds, the rock is mostly limestone with interbeds of anhydrite and shale.

Jan 9, 1968

By Kelvin K. Wu, Daniel S. Mazzei

As a result of the 1972 Buffalo Creek disaster, the Mining Enforcement and Safety Administration (MESA), now the Mine Safety and Health Administration (MSHA) initiated the draft of new federal regulations to deal with the mine waste impoundment and refuse pile problems. Public hearings were held and finally promulgated in October, 1976. As stated in 30 Code of Federal Regulations 77.214-216, the complete engineering design plan which is mandated by the regulations has to be approved by a coal mine health and safety district manager. During the past 18 months MSHA has gained considerable experience through the submission, review, and approval process. This report indicates the procedures, general design criteria and inspection requirements for submission of engineering plans to be approved. In particular, problem areas encountered most frequently by both operators and MSHA will be discussed. Only through diligent efforts by the operators, consultants and government, can we hope to accomplish the common goal to improve the safety of operations.

Jan 1, 1982

By Adrian E. Ross

DRILLING through caving formations in diamond drill holes at depths greater than 2000 ft has long been a serious problem. These caving formations are normally passed only by casing the hole or by cementing the hole. Casing the hole is possible only when a resulting smaller hole is acceptable. In as much as only a limited number of reductions are economically practical, cementing is frequently considered the only method suitable for solving these problems. Cementing either by pumping a slurry into the hole or by dropping cylinders containing cement has proved satisfactory on holes under 2000 ft. In holes substantially deeper than 2000 ft these methods are not satisfactory, since during the pumping process cement separates out, whereas cylinders usually break before the bottom of the hole is reached. A new procedure, the injector method, apparently solves these problems.* With this method, cement is lowered in the hole in a cylinder, the cement being

Jan 1, 1952

By H. W. Winkler, Discussion, V. L. Forsyth

The development of a new gar lift valve has removed many of the obstacles limiting over-all gas lift efficiency. The valve is pressure charged in place in a well, and operating pressure can be changed without pulling. Temperature and gas gradient compensation have been eliminated. Intermitting and constant flow installations, using conventional pressure-charged valves, are compared with designs incorporating the new automatic stabilizer controlled valve. Specific well performance data are presented. The means of obtaining and controlling multiple-point injection of gas are explained and contrasted with single point injection. The effect on small diameter strings and multiple string installations is discussed. The effect of flowing temperature gradient on a design using conventional pressure-charged valves, the limitations imposed by such temperature, and the obvious benefits which result from the use of automatic stabilizer controlled valves are shown. Reduction of gas requirements is stated mathematically and demonstrated with specific examples which are identified as to oil company and well. Increased fluid recovery resulting from greater drawdown is illustrated. The economic advantages are mentioned with emphasis on reduction of capital expenditures, as well as reduction in operating expenses. INTRODUCTION Much of the engineering and research work performed with gas lift has been based upon the supposition that under producing conditions gas would be injected at a single point in a well. Many tests were performed in determining the optimum size of the opening through which gas would be passed and the exact placement of the valve equipment. The objectives in a gas lift installation are to unload the well and to efficiently produce the well after it is unloaded. Until recently, the function of upper valves was simply to unload the well. An operating valve located at a proper place in a well served as a single injection point for lifting liquid to the surface. The basic problem in using such equipment is to arrive at operating depth with sufficient operating pressure to efficiently lift the liquid. Few gas lift installations are designed with all required well data available. However, regardless of the quality and availability of data, and regardless of the accuracy of the design, there is the practical problem of preparing and placing gas lift equipment in the well in exact accordance with the plans and intentions of the engineer. In recognition of these and many other problems, attention was directed toward a means of removing the need for temperature and gas gradient compensation, a way to change the gas lift installation to meet the changing requirements of the well itself, and a manner of compensating for changes in oil-water content, fluid volumes, PI, and bottom-hole pressure resulting from flood or repres-suring activity. A device which could actually set and change the operating pressure of gas lift valves in the well would meet most of these needs. There now exists a new gas lift valve which fulfills the original objectives and in so doing actually accomplishes much more. With this device, called an Automatic Stabilizer Controlled valve, there is an exact matching of valve operating pressure and well conditions. Gas is injected at more than one point in the well, thereby making controlled multiple-point injection of gas a reality. Installation calculations are materially simplified and the need for basic temperature and gas gradient data no longer exists. Section I—The Automatic Stabilizer Controlled Valve The operation of the ASC valve is more easily understood by first studying a conventional pressure-charged valve and then inserting the stabilizer element to observe the changes which result. Fig. 1 is a schematic of a conventional precharged pressure-operated valve. The pressure in the dome pd, acts downward, against the area of the bellows A,, to hold the valve closed. The resulting force Bf plus the spring effect of the bellows Sf represents the total force acting to close the valve. Correspondingly, the tubing pressure ptbg works upward against the port area Atbg and the casing pressure pc works upward against a portion of the area of the bellows

Jan 1, 1965

By Richard Moldenke

A. E. OUTERBRIDGE, JR., Philadelphia, Pa. (written discussion).¬ The fact that iron castings improve with age has long been known. Many years ago the late Sir Frederick Bramwell, a distinguished engineer, formerly in charge of the metallurgical and gun-making department of the Woolwich Arsenal, England, determined to break up a large number of cast-iron mortars of an obsolete type that had been in stock for years. It was then reported to biro that it was found to be much more difficult to break these old gun castings under the "drop" than it was to break similar gun-castings recently made, under his own supervision; he changed the.. composition of the iron and still found that whenever castings made recently were broken up (on account perhaps of superficial defects) great disparity was observed in apparent strength between the old and new castings. Sir Frederick then made many other comparative tests, such

Jan 4, 1917

By Lawrence Burkhart, S. B. Joo

Axially unsymmetric ordered circulation patterns on the surface of a hemispherical constant volume drop with forced Internal motion were considered as a manifestation of hydrodynamic instability, which was affected by internal flow as well as by the properties of the interface A simplified mathematical model was analyzed In order to study the mechanism of onset of interfacial circulation from a non-circulatory basic state. Values of the critical Reynolds numbers were obtained when the basic state became a fully developed rotational flow and the values changed for different interfacial properties. The work describes a heretofore unreported surface flow pattern on drop surfaces From a practical point of new, any motion in the interface of a droplet can have a significant effect of mass transfer rates in solvent extraction processes Although surface motion in droplets actual processing equipment is very complex, continued study of the fundamental nature of such phenomena should ultimately lead to more effective equipment design procedures.

Jan 1, 1981

By P. E. Chapman, J. E. Worthington, I. T. Kiff

Increases in the price of gold starting about six years ago, and rapid fluctuations since then, have created a substantial popular interest in the noble metal. Gold prospecting had been at a low ebb since the end of World War II in most of the United States, except for a flurry of activity in Nevada after the Carlin and Cortez discoveries. The last few years, however, have seen a great awakening of interest in gold exploration as well as an opportunity for education for many explorationists in the geology and other vagaries of gold deposits. The writers have participated over the last few years in a search for gold deposits throughout the United States. This search was greatly influenced by the geologic studies of Dr. William Spence at the Haile gold mine in South Carolina, as reported in a companion paper. Spence's studies resulted in definition of a geologic model that has proven useful in a number of other geologic environments in the United States. These programs were all carried out under the auspices of Cyprus Mines Corp. and permission by Cyprus to present these results is gratefully acknowledged. The writers, however, reserve for themselves all responsibility for the results and conclusions. The exploration program to be described began in the southeastern United States. Spence's studies provided a reasonable basis for interpreting and understanding the geology of the Haile deposit, and also provided a means for predicting additional occurrences. This concept was then expanded to other gold occurrences in the Piedmont, and became an effective tool for evaluating other prospects. Finally, it became evident that the concept could be applied in some western gold districts. The following discussion will then include descriptions of other Piedmont examples and a few western districts that also appear to fit the pattern.

Jan 1, 1981

By E. P. Pfleider, W. D. Lacabanne

ROTARY-percussive drilling is a new method of drilling hard rock. Designed to give variations in thrust, revolutions per minute, and torque ranges, these drills combine the high efficiency of the rotary system in soft rocks with an increasing amount of percussive action in rocks more difficult to fragment. Fundamentals of the rotary, percussive, and combination systems have been described in detail in various papers-most recently by C. Fairhurst and W. D. Lacabanne1-but there is still much basic work to be done on the interplay of actions in the rotary-percussive system to enable the drill designer to achieve the highest efficiencies. Whereas the original units struck light blows of only 15 to 30 ft-lb, adequate for medium hard rocks, the present trend is to piston blows of 50 to 65 ft-lb in order to cope with the granites and other rocks having Shore hardnesses of 75 or more.

Jan 7, 1957

By George C. Toland

In 1950 the phosphate fertilizer market warranted the design and construction of a new fertilizer plant by Cominco at Kimberley, B.C. The initial rated capacity of the plant was 70,000 tons per year of high- grade ammonium phosphate. The plant was placed on-stream in 1953. One of the major problems in operating the fertilizer plant was the disposal of the gypsum tailings slurry which was a by-product of phosphoric acid manufacture. The original weight of dry tailings produced by the mill was 500 tons per day. This quantity increased over the years until a projected 2200 tpd was selected for the pond design described in this paper. The original gypsum tailing area was located south of the fertilizer plant and adjacent to the St. Mary's River. By 1965 the original disposal area had proven inadequate and Cominco's engineering staff had selected a 500 acre disposal site to the east of the plant.

Jan 1, 1971

By H. E. Sadler, B. Silliman

INTRODUCTORY NOTE. THE research here recorded was undertaken early in the present year, and has been prosecuted steadily for about eight months. While the work has been under my constant supervision and advice, the labor has all been performed by Mr. Sadler, to whom is chiefly due the development of the successive steps which have led to the final result. The process is better than I dared to hope, and we are able to place at the command of chemists and engineers interested in the matter an apparatus of continuous and uninterrupted action, and methods of analysis by which the daily averages of the two variable and inconstant factors of illuminating gas, ammonia and sulphur, may be determined with all needful accuracy, even by those little skilled in chemical manipulation, and with very little loss of time. This research has been carried out in the laboratory of the New Haven Gaslight Company. B. SILLIMAN. October 17th, 1876.

Jan 1, 1877

By A. Haas, L. Bubenicek

The Lorraine deposit of minette iron ore has been mined for more than a century. During this time, the economic conditions have changed frequently, and especially during the past decade. Thus, it has become economically prudent to proceed to new iron ore reserves with consideration of many and varied parameters. In the past, only traditional mining parameters were considered. Today, the quantity of information that must be taken into account is of such magnitude that the only practical means of data processing is by use of a digital computer and a mathematical model. One such model, based on geostatistics, was developed by G. Matheron. Much of the required input information, such as the petrology of ores, has been generated through IRSID investigations. This paper deals with several aspects of data processing in mining including information recording, reserves calculation, and stages of shrinking data in the calculation of mining iron beds, variograms, kriging, and tonnages.

Jan 1, 1969

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 R. S. Shoemaker, D. L. Harris

PST investigations into the possibility of concentrating the low-grade iron ores of the Gogebic Range in Wisconsin have been hampered by the complex association of the constituent minerals. In part the problem arises from the fact that the iron occurs essentially as two minerals, hematite and goethite, having nearly the same chemical composition but exhibiting different physical properties. Individual grains of these minerals are usually so small that the ore must be ground to a size finer than 325 mesh if substantial liberation of the minerals is to be secured. Appraisal of beneficiation tests on this iron ore requires, therefore, some method of determining quantitatively the contents of constituent minerals in the various products of the beneficiation. Because of the chemical similarity of the two iron minerals, chemical analyses do not provide a means of differentiation. Although the minerals are different physically, they are both opaque and friable, and as the ore must be ground to a very fine size for liberation to be secured, quantitative microscopic methods of analysis are extremely difficult at best. In an effort to overcome these analytical problems, a quantitative X-ray diffraction analysis method has been developed at the University of Wisconsin for the research program on iron ore beneficiation. The X-ray diffraction analysis of chemical compounds of crystalline form has proved of inestimable value for structure studies and rapid qualitative analytical purposes in a number of fields.' In some cases X-ray diffraction analysis has been found suitable for quantitative determinations. H. P. Klug2 found that quantitative procedures for quartz powders when mixed with calcium fluoride were reproducible within ±1.0 pct. Talvenheimo and White3 reported quantitative analyses of clay minerals to be accurate within 10 pct and also detected 1 pct of bentonite in 99 pct illite. In other investigations,'" powders of quartz and mica have been analyzed quantitatively with accuracies from 1 to 5 pct. A powder of tungsten carbide was analyzed similarly by Redmond7 and Rooksby8 reported the determination of small amounts (0.11 pct) of calcium oxide in magnesium oxide. In the most generally practiced use of X-ray diffraction, traces of the diffracted beam are recorded as lines on a film much as lines of elements are recorded on an optical spectrograph film. As with the spectrograph, the darkness of the lines denotes the amount of the constituent in the sample. If the film is replaced by a Geiger tube assembly and a graphic recorder or a scaling unit, the intensity of the diffracted beam can be registered as a peak on a chart or energy impulses per unit of time on the scaler. Several methods of quantitative measurement have been investigated and reported in literature. Klug2 used manual operation of the goniometer and a counting technique to determine the difference in counting rates at the diffracted angle and for the background. In another case3 the area under the recorded diffracted peak was the basis for the determination. In other instances the height of the recorded diffraction peak above background, measured while the goniometer was moving, has been the basis for the measurement. The sizes of particles most suitable for diffraction techniques are reported in the literature as follows: for tungsten carbide a maximum of 40 microns7 and for quartz a maximum of 5 microns.' Very fine sizes of crystals are known to cause a broadening of the diffused beams; hence some workers have set a lower limit of 0.1 micron for quantitative results. Guinier10 has indicated that broadening of the diffracted X-ray beam is not appreciable for crystallites larger than 0.02 to 0.03

Jan 1, 1956

By R. C. Hyslop

The object of this experiment was to obtain a usable set of field curves for determining the susceptibility of rocks with the vertical magnetometer. The need often arises for determining the susceptibility of rocks in the field in order to interpret magnetic anomalies obtained. This is particularly true when diamond drilling has been done and the relation to the surface rocks of the samples taken is desired. Many methods of measuring rock susceptibility have been developed, but in general they require careful shaping of the sample or pulverizing it in addition to delicate laboratory measuring instruments designed for the purpose. The requirements for a practical method for the determination of susceptibilities are as follows: 1. There should be as little alteration as possible of the specimen. 2. A minimum of time should be required in the preparation of the specimen and the calibration of the equipment. 3. Theequipment used should be portable. 4. An accuracy within the limits of the survey at hand should be obtainable. 5. A means of measuring the remnant magnetism should be available. Laboratory Procedure With these ideas in mind, the problem was approached in the manner in which Koenigsbergerl developed his method using the principle of the electrical theory of images of Lord Kelvin and applying it to the magnetic case. This solution of the problem states that the apparent change in the magnetic field intensity AZ due to the proximity of a specimen is given by: mk AZ = 2a2 Where k is the susceptibility of the specimen, m the strength of the pole of the needle, and a its distance from the surface of the specimen, as shown in Fig. r.2 This relation is true only for an infinite body and corrections are necessary for a finite body. Koenigsberger used in his work a variometer of special design. He suggested that a Schmidt vertical balance or horizontal magnetometer, as well as some other instrument, might be used. The Colorado School of Mines horizontal torsion magnetometer operates on this principle. In the

Jan 1, 1946