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By M. E. Tyrrell

The Bureau of Mines produced building brick of good quality in an investigation designed to explore the possible utilization of high-glass fractions of municipal incinerator residues in the manufacture of building products. Common clays, lime, and sodium silicate were used as binders for the nonplastic residues Test bricks were formed by dry-pressing, soft-mud molding, and stiff-mud extrusion. A run of standard-size face brick dry-pressed and fired in the West Virginia University Coal Research Bureau pilot plant demonstrated that SW-grade glass-clay face brick can be produced on a commercial scale without difficulty. A cost evaluation made for production of the brick showed an estimated cost of $42.13 per thousand bricks for a shuttle kiln plant and $28.70 per thousand for a tunnel kiln plant.

Jan 1, 1972

By H. N. Eavenson

The eleven mines of the United States Coal and Coke Co. in the Pocahontas coal field are situated in McDowell County, W. Va., which is a mountainous region. The valleys rarely exceed 200 ft. (60 m.) in width, the hillsides slope from 25°to 33°, and the tops, from 600 to 900 ft. above the valleys, carry practically no level land. At least 80 per cent. of the area is covered with timber. All the workings are drift mines; and while the average grades of the seams worked are ample for drainage, local dips and swamps necessitate the use of a large number of local pumps or of numerous drainage ditches to keep the mines free from water during heavy rains. The water handled in any mine is not great, compared with the coal output, and usually causes little trouble except during extremely wet periods. In new workings, the water encountered, except in rare cases, is trifling; it is only after rib drawing has started and the surface has been broken that water troubles begin. The strata overlying the coal are sandstone, shales, and slates; as the soil is thin and sandy, it does not tend to puddle and stop the cracks, which remain open for a long time. As mining progresses and the robbed area increases, the broken area becomes larger, increasing the openings into the mined territory. The cover over the robbed portions of the mines varies from 30 to 750 ft. (9 to 228 m.). When the ground is saturated, considerable water finds its way into the mines the day after a heavy rainfall and for three or four days it tends to fill the low places, wash the tracks, etc. and unless from three to four times as many pumps are installed as are normally needed, considerable output is lost. In most cases the water will flow from the mines, and the obvious solution is to provide drainage ditches of ample size to carry the maximum flow expected, so that the inflow will have no opportunity to flood the working places. Laying out the drainage headings on the proper average grades was an easy matter but where blasting was necessary to provide uniform grades, as was frequently the case, it was important that the maximum flow to be expected and the size of ditches to be provided should be known so that only rock work necessary to provide proper drainage

Jan 1, 1922

By E. H. Kelton

The purposes of this paper are to describe the use of adjustable cut and draw tools as a control test of drawing properties and to point out that no other well-known test or combination of tests determines this quality in zinc and zinc alloys. Rolled zinc has been used for making drawn articles, particularly battery cans, for many years. The development of rolling treatments satisfactory for these purposes followed the usual course of trial and error experimentation depending upon cooperation with customers to determine what type of material was suitable. A quick test of drawing quality was highly desirable, of course. Scleroscope hardness and temperll having no apparent relation to drawing quality, were used simply to check the duplication of rolling treatment and grade of metal. The dynamic ductility1 test, on the other hand, was believed to be so like the drawing operation as to provide a reliable index and came to be taken as the criterion of good drawing properties. Faith in this test was strengthened by the fact that metal having the highest ductility was more satisfactory for operations, such as the manufacture of battery cups, that required several redraws. No distinction was made at that time in specifying metal as to whether it was to be subjected to simple cut and draw, redrawing or forming operations. It developed, however, that in some grades of metal the highest ductility did not coincide with the most satisfactory quality when the material was used for a single draw. When zinc-base alloys, with their wider ranges of effective rolling treatments, came into increased use, their dynamic ductility and drawing quality appeared to have no connection whatever. Furthermore, comparisons of known drawing quality with other physical properties of the metal, including tensile strength, elongation and dynamic cold bends, were fruitless in yielding any clear relationship. Almost any test value produced in one piece of metal could be duplicated by another rolling or annealing treatment with attendant different drawing characteristics.

Jan 1, 1934

By J. H. Schulman, M. H. Buckenham

Although much interest has been taken in the use of mixed collectors in flotation, this investigation is probably the first in which oppositely charged collectors have been considered. The results obtained and the techniques used could well be applied in the behavior of other mixe the behavior of other mixed collector systems and could possibly explain the effective flotation results which have been reported when various collector combinations have been used. Collectors conventionally employed in flotation systems are soluble in water, but many of their homologs of longer hydrocarbon chain length are insoluble. The properties and behavior of these insoluble compounds may be conveniently studied when they are spread as monolayers at the air/water interface on the Langmuir-Adam trough. Although some extrapolation is involved in applying effects observed at this interface to the solid/liquid interface where the action of collectors is most important in flotation, the technique nevertheless is most useful for the study and interpretation of flotation phenomena. Of particular interest in this field are investigations on the insoluble monolayers of the fatty acids, alkyl sulfates and alkyl amines; the penetration of these insoluble monolayers by soluble surface active components and their interaction with metal ions from the underlying solution.'-' Unfortunately, the insoluble xanthates and related compounds do not exhibit stable monolayer properties due to rapid oxidation at the air/water interface and, therefore, cannot be studied directly in this way. These approaches have enabled Leja and Schulman8 to suggest mechanisms explaining dynamic attachment of mineral particles to air bubbles involving collector-frother interaction and the adsorption of collectors onto mineral surfaces. In this and other papers 9-12 considerable evidence is presented to support the concept of collector-frother and metal ion-monolayer interaction and to emphasize the value of monolayer techniques in elucidating the flotation system. Molecular interactions resulting from monolayer penetration are determined by the nature of and the association between both the polar and nonpolar groups of the two molecules concerned. Stable complexes are formed on penetration when interaction takes place between both the polar and nonpolar groups, and although the resultant complexes are not necessarily true chemical compounds, the properties of the molecularly associated complexes are very different from those of the individual components. Shortening of, or changes from, a straight hydrocarbon chain in one of the reacting molecules reduces considerably the stability of the associated complex as do changes in temperature, pH and substrate composition. The effect of hydrocarbon chain length becomes most important when observed effects are to be applied in flotation studies where soluble homo-logs and, therefore, much shorter hydrocarbon chain lengths are used. The present investigation is based on Langmuir trough work carried out by Bowcott,l3 who studied the penetration of insoluble amine monolayers by potassium lauryl xanthate. Bowcott observed that cetyl amine monolayers were readily penetrated by xanthate, but found that with time the high film pressures resulting from penetration and association fell off, indicating decomposition and ejection of xanthate from the film. This decomposition was pH dependent. Of particular interest in this work were studies on an equimolecular mixed monolayer of the fully N-substituted ammonium compound, for example, cetyl trimethyl ammonium iodide (CTAI) and potassium cetyl xanthate. Despite the fact that the CTAI is water soluble and the xanthate on its own is incapable of forming a monolayer, the mixed film was stable up to a surface pressure of 67 dynes per cm. In this condensed state the xanthate was stabilized against atmospheric oxidation, although iodine injected beneath the film caused an immediate collapse. The stabilizing of xanthate against oxidation by association with an alkyl trimethyl ammonium bromide (TAB) could be important in flotation, and a study of the performance and behavior of mixed collectors therefore was undertaken. A modified Hallimond tube operated under controlled conditions was used to evaluate flotation. Surface tension measurements were made to investigate the properties of the soluble

Jan 1, 1963

By C. Dai, S Raathiv

The Waikato Expressway is one of the New Zealand Transport Agency’s (NZTA) seven roads of National Significance. Coffey is part of the City Edge Alliance engaged by NZTA for the Hamilton Section of the project. The 22km Hamilton Section is the largest and most geotechnically complex section of the Expressway. The Mangaonua gully in Sector 6 is the most challenging geotechnical area of the project for piling works. Together Coffey and Brian Perry Civil have carried out the temporary and permanent design and construction of embankments, piling works, retaining walls and soil improvement works for the bridge construction. The design and construction works were governed by weak alluvial layers and artesian pressure layers several meters beneath the ground level. This paper presents the action taken to improve the foundation of temporary platform, control the artesian pressure, prevent bentonite leakages into the highly permeable alluvial layer and challenges in the base grouting process. This paper summarises the key components in the construction and supervision of bored piling works and outlines innovative solutions for challenges which we faced during the construction.

Nov 1, 2022

By M. D. Seke

The flotation response of a Pb-Zn sulphide ore from the Rosh Pinah Mine (Namibia) was studied in the presence of inorganic depressants such as sodium cyanide and zinc sulphate. Poor flotation selectivity was observed in the rougher concentrate of the galena circuit despite the use of a large amount of sodium cyanide. Batch flotation tests have shown that the use of cyanide alone is not efficient for the depression of sphalerite from the Rosh Pinah ore when milling is carried out according to the current plant particle size distribution. The use of both cyanide and zinc sulphate improved the selectivity between galena and sphalerite much better than cyanide alone. Flotation selectivity is limited by the mineralogical texture of the Rosh Pinah ore sample. Microscopic analysis has shown that the presence of sphalerite in the galena concentrate is also due to poor liberation between galena and sphalerite, especially in the middlings. Hence, selectivity could be improved by regrinding the rougher concentrate prior to the cleaning stage. Keywords: sulphide ores, flotation, flotation depressant, mineralogy.

Jan 1, 2005

By Lachlan Gilchrist

MEASUREMENTS of resistivity by methods involving the use of two current electrodes and two potential electrodes in general collinear with the current electrodes have been made extensively in geophysical investigations. In the method developed by Wenner and made use of by Gish and Rooney, and later in a modified form by Lee, the distance between the current electrodes is divided into three equal parts by the potential electrodes. In one of the methods developed by Schlumberger prospecting methods and by Koenigsberger, one current electrode is placed at considerable distance from the other and potential measurements are made in the immediate neighborhood of one of the current electrodes. The method is described as the single current electrode method, and the effect of the distant current electrode is considered negligible or a correction is made for the effect in the calculation of the resistivity. Usually the correction that is introduced is based on the calculated effect for measurements made in a homogeneous conducting material. The useful application of these methods in prospecting for minerals, of course, is in regions where nonhomogeneous conditions exist. In many of these conditions it is very doubtful whether the effect of the distant current electrode may be neglected, except for measurements in the immediate neighborhood of the "single" current electrode, and corrections based on homogeneity of the medium will necessarily be inadequate. In order to obtain a degree of symmetry that would preclude the necessity for corrections for the distant electrode and that would simplify interpretation, it appeared desirable to use a central current electrode and a set of distant end current electrodes symmetrically placed about the central electrode as shown in Fig. 1 and to provide by means of auxiliary resistances that the currents passing into the earth at the distant end electrodes should be equal. Circumstances did not permit the operation of this plan in complete detail but a degree of symmetry was obtained by using a central current electrode and two distant collinear end current electrodes and by taking measurements along a line passing through

Jan 1, 1931

By D. Grosse

At the beginning of the 1960's, the Hannoversche Portland-Cementfabrik A. G. needed to open a new quarry. The land on which this quarry was to be developed was completely flat and separated from the existing quarry by a navigable canal. The area had been exploration-drilled previously, so that enough reliable data on the chemical properties of the deposit were available. From the geologic point of view, the deposit under a very moist surface belongs to the Turon (Upper Chalk) formation, soft on the surface and medium to very hard farther down. Between the 15% sloping banks of chalk (with a calcium carbonate content of 75 to 90% and running from west to east), there are numerous beds, up to 3 m deep, which are rich in alumina and iron oxide but contain only 50 to 60% CaCO3. In the old quarry-worked conventionally by deep-hole drilling, a 2-cu-m shovel, and 900-mm track with 6-cu-m dump cars-an adequate and modern crushing plant was available. The plant crushed the moist material (11 to 13% H2O content) down to 0 to 50 mm. INSTALLATION OF ORIGINAL MOBILE CRUSHER It was decided to employ a mobile crushing unit in the new quarry; the moist and soft ground did not permit the use of heavy trucks for transporting the material, and a road network would have entailed a large investment. The use of a rail system was eliminated from the beginning, since the ground would be very uneven after the quarry was developed. At that time only one prototype of a crawler-mounted mobile crushing unit existed. This unit was operating in a nearby works as a primary crusher. A similar, slightly improved machine (Fig. 1) was purchased

Jan 1, 1969

By John B. Spencer

Earlier this year, Simplot Phosphates achieved a safety milestone at its Vernal, UT phosphate operations. In March, the entire operation reached achieved seven years without a lost time accident. And the mine operations at Vernal reached the 1 million hours benchmark without a lost time accident. This million hour achievement has been 19 years in the making. This achievement reflects the mine’s strong attitude towards safety, the company said. Safety is an integral part of its culture and requires diligence and considerable work. Attention to even the smallest of details cannot be allowed to slip. This is a record Simplot Phosphates said it hopes to improve on every day.

Jan 1, 2004

By Charles E. Glass

The purpose of this report is to demonstrate the flexibility of rte sensing techniques for providing data with which to implement mined-lands reclamation in an efficient and cost-effective manner. An operational program is presented for using satellite remote sensing data, collateral data, and automated image analysis to provide: 1) an inventory of coal and copper mines and mine waste in Arizona, 2) techniques for periodic monitoring of mining areas using multitemporal classification and image prediction techniques, and 3) delineation of high priority areas for future reclamation and current land-use planning of Arizona mining areas based on environmental hazards indices computed using classified scenes and collateral data.

Jan 1, 1980

By J. W. Taylor, E. G. Zukas

THE results of shock-loading studies on copper were reported several years ago by smith. In his experiments, Smith found that there was a correlation between the shock direction and the orientation of twins which the shock produced. By using free-surface-type shots in which the free surface of the specimen was not normal to the shock direction, he showed conclusively that twinning of copper in impulsive loading was caused by the rarefaction wave. Similar tests with iron, however, showed that it twinned during compression. More recent studies of iron2 and on Fe-Si single crystals3 have shown that twinning can be suppressed in these materials by shock loading at pressures high enough so that the velocity of the shock wave exceeds the elastic-wave velocity. From these observations, it appeared that twinning was caused by the shear stresses present in the zone undergoing adjustment from one-dimensional to three-dimensional loading. At high pressures, such a zone becomes so thin that there is insufficient time for the relatively ordered motion of atoms involved in twinning to occur. Twinning in copper, therefore, cannot be produced by a single compressive shock wave because resolved shear stress large enough to create twins exists only for a very short time (0.01 psec or less) before the pressure increases suddenly and loading becomes essentially hydrostatic. (A typical pressure vs time record for a copper shot, illustrating the short rise time of the compression wave, is shown in Fig. 1.) If, on the other hand, a second shock wave can be created in a precompressed sample, then the new elastic limit is several kilobars,4 and a resolved shear stress sufficient to cause twinning should be maintained for an adequate time period (0.1 psec or more). This experimental situation can, in fact, be realized. The experimental arrangement used to do so is shown in Fig. 2. By utilizing the pressure transformation in Fe-V alloys, it was possible to shock-load the copper in compression while the copper was already precompressed. In the first test, an 8 wt pct V-Fe sample was used as a driver for loading the copper, and the copper was exposed to the following series of compressive shocks: 1) an elastic wave of about 8 kbars, which is usually ignored in shock studies; 2) the pressure transformation wave for the driver of 200 kbars; and 3) the driving shock wave of 270 kbars pressure. Metallurgical determination of the angular twin distribution, shown in Fig. 3, with respect to the shock direction and the shock rarefaction direction (which was 23 deg from the shock direction) showed that twinning took place

Jan 1, 1965

By R. W. Armstrong, P. C. Jindal

The hardness dependence on grain size for polycrys-talline cartridge brass and a leaded brass has been measured by Brine11 and Rockwell B testing. In each case, the hardness, H, depends on the average grain diameter, 1, according to: H =Ho + kHl-1/2 where Ho and kH are experimental constants. Diamond pyramid hardness values have also been measured as a function of the indentation size and grain size to give additional information on the nature of the hardness test and the dependence of hardness on micro-structure. The hardness of polycrystalline brass depends on its grain size. Bassett and Davis' demonstrated this as early as 1919 by making Brinell hardness measurements on cartridge brass. Since then, the hardness of this type of material has been measured as a function of grain size by making Rockwell,2'3 Vickers,4 and Brinell5 tests. he hardness dependence on grain size has also been measured for other materials. Angus and summers6 investigated the grain size dependence of the Brinell hardness of polycrystalline copper and a Cu-4.5 pct Sn bronze. In other studies, nickel,? Armco iron,Big an Fe-0.07 pct C alloy,I0 and an 0.39 pct C-12.45 pct Cr stainless steel" have been investigated. In some of the preceding cases, the hardness results have been analyzed to show that the hardness varies with the average grain diameter, 1, according to an l-l\4, l-1/4 or I-2 dependence,11-13 The studies of the influence of grain size on hardness have not been based on any theoretical model. This may be because the hardness of a material is itself a complicated property. However, attempts have been made to correlate, experimentally and theoretically, the hardness of a material with its unidirectional stress-strain behavior.14-l6 On this basis, Hall" proposed that the polycrystal hardness dependence on grain size might follow directly from the Hall-Petch18,19 relation for the grain size dependence of the yield stress. Thus, the hardness-grain size relation was given as: H = Ho + kHl-1/2 [1] where Ho and kH were taken as experimental constants. The relation was applied to the measurements on brass,' copper,6 bronze,= and Armco iron.' More recently, this relation was shown by Armstrong and jindal20 to adequately describe the measurements on cartridge brass made by Bassett and Davis' and Babyak and Rhines.5 In this case, the relationship was taken a step further by independently relating the values of Ho and kH to the values of oyand ky, previously reported by Armstrong, Codd, Douthwaite, and petch21 from measurements of the yield stress dependence on grain size for this type of material. In the present investigation, new Brinell and Rockwell B hardness measurements have been made as a function of grain size for a cartridge brass and a leaded brass. In addition, diamond pyramid hardness values were measured as a function of the indentation size. All these results are applied to a further analysis of the hardness dependence on grain size. MATERIALS AND EXPERIMENTAL METHODS Cartridge brass and a leaded brass were selected for this investigation for two main reasons: it was anticipated 1) that these materials could be cold-worked and recrystallized to a wide range in grain size and 2) that the results to be obtained on these typical industrial materials could be usefully compared with previous investigations. The chemical analyses of the actual materials which were employed are given in Table I. The as-received 1/2- and 3/4-in.-thick plates were given various reductions in thickness by cold rolling. The rolled material was heat-treated at various temperatures between 330" and 850°C for differing time periods from 5 min to 9 hr to achieve a variation in the average grain diameter between 0.0339 and 0.000543 cm.22 During heat treatment, the brass was protected from zinc loss by packing it in chips or foils of the same composition material. Reasonably equi-axed grain structures were obtained in each case. The metallurgical grain sizes of the specimens were determined from measurements of the average linear intercept on a random line. Annealing twin interfaces were not counted along with grain boundaries. The

Jan 1, 1970

By Steven Putt

Seismic While Drilling (SWD) is a newly developed technology in the mining industry. Improving upon Measurement While Drilling (MWD) systems, SWD measures mechanical properties of the rock at incremental depths down a blast hole at a much higher resolution. SWD is also immune to common failures and inconsistencies of MWD such as operator and drill specific variation. Seismic While Drilling records the velocity and elastic modulus of the rock with centimeter accuracy in real-time. These properties measured while drilling blastholes are then used as a proxy for density which can be used for: • High resolution geologic modeling • 3D ore control • Drill and blast optimization • Drill to mill tracking One of the distinct challenges with SWD systems is the sheer volume of information acquired. With thousands of measurements per blasthole, the data can be overwhelming for even an experienced engineer. To overcome this complex challenge, the latest cloud computing and analytics models have been simplifying and organizing the data. These newer technologies can amplify an engineer’s capability by delivering actionable insights into their drilling and blasting workflows. The paper presents new results from Datacloud during recent Seismic While Drilling trials in iron ore, metallurgical coal, and hard rock mines around the world. The measurements are compared with wireline geophysical logs, core data, drill cuttings, and conventional measurement while drilling (MWD) systems to validate the technology and show how the data can be used.

By John T. Norton, R. E. Hiller

The tremendous increase in the use of metals that have been prcpared by the various cold-working processes during recent years has greatly stimulated the investigation of problems concerned with the fundamental nature of these processes. It has been observed in practice that different methods of bringing about the same dimension changes in a sample result in a rather wide range of properties. Cold working reduces the ductility of a metal, or what is perhaps more nearly correct, its "working capacity," and naturally the manufacturer wishes to produce an article that has as large a working capacity as possible, and to produce it with the smallest number of operations. It has also been known for some time that cold deformation produces a parallel alignment of the crystal grains of a metal, and that the type of this preferred orientation depends to some extent at least upon particular processes employed in the deformation. The present investigation has for its purpose the study of the relations between the various factors of a cold-working process and the preferred orientation of the metjal crystals resulting from this deformation. The work is chiefly confined to a study of cold-drawn seamless tubing. Preparation of Samples The tubing samples used in this investigation were made of steel having a carbon content of 0.10 to 0.20 per cent, and were drawn on a standard type of draw bench. In order to obtain the large reductions, the annealed stock was coated with lead, for purposes of lubrication. The reductions of area stated refer to reduction from the annealed condition without intermediate heat treatment. The cold work was done as nearly as possible at room temperature. The samples of wire and strip used for purposes of comparison were of steel of approximately the same carbon content and were prepared in the manner indicated. X-ray Method of Investigation The condition of preferred orientation in cold-worked samples is best investigated by the X-ray method that employs a small circular beam of * Assoriate Professor of Physics of Metals, Massachusetts Institute of Technology. t Graduate Student, Department of Metallurgy, Massarhusetts Institute of Technology.

Jan 1, 1932

By E. C. Lane

During the past 15 years the Bureau of Mines has made and published several hundred analyses of typical petroleums and has developed a system of interpreting the analyses and of classifying crude oils. In describing crude petroleum frequent reference is made to the "base" of the oil, a usage the petroleum industry has found convenient. As part of its general study of the characteristics of crude oils, therefore, the Bureau of Mines has developed a system of classifying them according to "base." This system as first published in 1927 was limited to four classes and in its original form is no longer considered adequate. Since the system was first published the Bureau has analyzed a large number of crude oil, including representative samples from nearly every important producing field in the world, and has found that the system of classification could be revised and amplified to advantage. The revised system is presented herein.

Jan 1, 1935

By cheng Peng-fei, TANG Hai-yan, guo Xiao-chen, LI Jing-she, Liang Yong-cang, Zhao Baojun

The origin and evolution of non-metallic inclusions for Al-killed casing steel during EAF-LFVD- CC process were studied by industrial tracer experiments. The formations of Al2O3 and MgO·Al2O3 micro- and macro-inclusions from ladle slag were analyzed by theoretical calculations. The results show that micro-inclusions were formed during deoxidation and temperature decreasing in the process of casting, most of the macro-inclusions come from entrapped ladle and mold slags. In addition, most of the Al2O3 formed were modified into 12CaO·7Al2O3 and 3CaO·Al2O3 inclusions which are liquid at steelmaking temperature. MnS cannot be fully modified to CaS and it was only wrapped outside the alumina or calcium aluminate in the form of (Ca,Mn)S with the amount of Ca-Si wire fed during the test.

Jan 1, 2016

By J. G. Richardson

The performance of laboratory water floods is compared with the flooding behavior calculated by the Buckley-Leverett techniques from steady-state relative permeability-saturation relations. Both the steady-state and unsteady-state experiments were conducted on the same sand-packed column. Relative permeabilities were calculated by the Welge technique from the unsteady-state waterflooding displacement experiments and compared with those measured by steady-state techniques. An evaluation of the various calculation procedures was made. It was demonstrated that steady-state relative permeabilities could be used to calczcJate waterflood performance. INTRODUCTION To calculate the waterflooding behavior of a given reservoir, relative permeability-saturation relations of the reservoir rock are required. These relative permeabilities are commonly measured on core samples by steady-state experiments such as the Penn State technique.' The relative permeabilities obtained in steady-state experiments are calculated from oil and gas flow rates and pressure drops measured under conditions of equilibrium distribution of oil and water in the pore spaces with slow approach to equilibrium. On the other hand, in water floods the water saturation at a given point changes rapidly with time as the flood front passes. Extensive research2 has shown that the steady-state relative permeabilities to oil and water are independent of the rate of flow and the fluid viscosities. Research has also demonstrated that the waterflooding performance of homogeneous sands uniformly contacted by water is independent of rate when capillary pressure gradients, which are important in short laboratory columns, are made negligible. However, there is little experimental data in the literature comparing relative permeabilities calculated from steady-state flow experiments with those calculated from flooding experiments. In this paper, the production data of two water floods and the relative permeabilities calculated from a series of steady-state experiments on an unconsolidated sand column are presented along with the comparisons calculated by the Buckley-Leverett and by the Welge techniques. The purpose of this study was to determine if steady-state relative permeabilities could be used to predict the waterflooding performance. This study also permitted an evaluation of the Buckley-Leverett and Welge calculation procedures and allowed an insight into the nature of microscopic displacement of oil by water. EXPERIMENTAL APPARATUS AND PROCEDURE The apparatus used in this investigation was a Lucite column 1 ft long and 11/2 in. in diameter. A drawing of the apparatus is shown in Fig. 1. Six pressure taps were evenly spaced along the top of the column to measure the oil pressures. Three pressure taps fitted with small porous disks were spaced along the side of the column to measure water pressure. Water was admitted to the inflow face of the sand through a porous disk while oil was admitted through a hole in the porous disk and distributed to the face of the sand by grooves machined in the porous disk. Retainer screens of 325-mesh stainless steel were cemented over the inlet and outlet ports and the pressure taps to prevent loss of sand. The column was packed with a clean dry sand all of which was finer than 200 mesh. Next, the sand was saturated with a solution of 150,000 ppm sodium chloride solution. The column was weighed dry and water-saturated to obtain data for the calculation of the pore volume. A 151-cp oil was then injected into

Jan 1, 1958

By John W. Trammell, Chester O. Ensign

Efficient mining of copper ore at the White Pine mine in Michigan's Upper Peninsula is partially dependent on the rather unique problem of predicting variations and rock types in a barren stratum called the upper sandstone. The pronounced effect which this formation has on the local mining techniques is reflected by the necessity of deciding whether to mine the sandstone along with ore-bearing rock, thus diluting overall ore grade, or, alternatively, leaving the sandstone behind to form the mine roof. THE OREBODY AND MINING TYPES In the mine, the cupriferous zone of the Nonesuch shale is divided into three major portions (Fig. I). Lying conformably on top of the Copper Harbor formation (or "lower sandstone") is the lower part of the orebody, the parting shale. The parting shale is overlain by the upper sandstone. On top of the upper sandstone, the basal portion (8 ft) of the upper shale is quite similar to the parting shale. Both the upper shale and parting shale are divided into a number of smaller stratigraphic units, each having a characteristic copper content, as shown by the histogram of Fig. 1. Other authors have dealt in detail with the stratigraphy and mineralogy of the orebody, so it will suffice here to call attention to the low copper content of the upper sandstone.

Jan 12, 1964

By Susan B. Bealko

Mining provides a large part of the energy and raw materials that feed this Nation's economy. Copper pipe, concrete, and window glass serve as well known examples of the reliance on minerals in modern society. Less appreciated, but as important, are the hundreds of mined commodities that are an integral and necessary part of everyday products, ranging from medicines and computers to carpet and paper. Coal is a major portion of the country's energy mix today, as it will likely continue to be in a future hydrogen-based economy. The domestic mining industry also provides strategic minerals that are important for the Nation's security. The processes to recover these mineral commodities are among the most demanding and complex in an industrial society, and this inherently dangerous industry has historically had the highest risks of fatality and injury. The mining industry has been undergoing some trying and challenging times because of the recent mine disasters in the coal fields. These events have been alarming in light of the strong and encouraging safety record that has characterized mining in the United States for most of the past decade. While mining communities deal with their grief, mine operators, government regulators, and other safety personnel, set about trying to determine why these fatalities occurred. Subsequently, the mining industry is currently experiencing changes in legislation at an unusually rapid pace. The most recent regulatory changes are the Mine Improvement and New Emergency Response Act of 2006 (MINER Act) and the temporary emergency standard for mine seals. The new mine safety laws call on the nation's mines to adopt certain procedures and safety technologies immediately, or as soon as they become commercially available. Putting all the provisions in place from these new laws is a major undertaking, and will necessitate strong collaborations and partnerships among mine operators, manufacturers, regulatory and research agencies, labor unions, and community groups. It is against this background that Prevention through Design (PtD) components for the Mining Sector are recommended.

Jan 1, 2008

By D. K. Crampton

The object of this work was to obtain and correlate information on effect of internal stress in variously drawn tubes on several properties. Also, a simple approximate method of comparing types of stress distribution in such variously drawn tubes was sought. There is also included some work on comparison of single and polycrystalline materials and effect of different types of operation and preferred orientation. Preparation of Material A series of tubes was drawn to study the effect of the type and degree of final reduction on various physical properties and the approximate distribution of stress intensity across the tube wall. The material used all came from a single heat of 70-30 brass melted in a regular production Ajax-Wyatt induction furnace. The analysis of the metal as cast was: copper, 70.36 per cent; lead, 0.04; iron, 0.02; zinc, balance. The material was cast in "shells" with 4 in. outside diameter and in. wall thickness. It was drawn part way down according to the usual standard mill schedule and then by suitable individual schedules to finish by a variety of types and degrees of drawing to the same final cases in every instance; namely, 0.750 in. outside diameter by 0.080 in. wall thickness. The exact final draws, together with the percentage area reductions, diameter reductions and gage reductions are given in Table 1. In fabricating these tubes, rather unusual precautions were observed to insure the elimination of ail variables not under immediate study. All intermediate anneals were carried out at about 1200" F. down to the so-called "cut-in size"; namely, 17/16 by 3/16 in. From this point on, all anneals were made at from 1050' to 1100" F. The greatest care was used all through to have the tubes as free from minor surface defects as possible. When such defects were visible on intermediate sizes they were carefully filed out. On the final draw to 3/4-in diameter the die was aligned with the greatest possible precision in order to insure as straight a tube as possible

Jan 1, 1933