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By Charles Fulton

The study of the condensation of zinc from its vapor was undertaken to shed light on certain problems encountered in large-scale electric zinc-furnace work recently conducted. It is a matter of common knowledge that one of the disadvantages of the arc type, electric zinc furnace, is the production of a large amount of blue powder and proportionately little liquid spelter, for, as stated by Stansfield,1 "A notable defect in the electric smelting of zinc ores is the difficulty experienced in obtaining the distilled zinc in the liquid state; when zinc ores are smelted electrically, very little liquid metal is commonly obtained, nearly all of the zinc being in the state of powder."

Jan 8, 1918

Single orders 2.5 c. Pamphlets 10. c. each in lots of three or more. Pamphlets 5 c. each in lots of fifty or more. These prices prevail for orders for pamphlet, of the same or different titles. The pamphlets listed on the following sheets are advance copies printed to facilitate discussion at the meetings of the Institute. They are offered for sale at the reduced prices given above as long as the supply, lasts. This list is published in the Bulletin in order that members may have the first opportunity to secure pamphlets, which sometimes are in such great demand that the supply is exhausted before the wants of members can be supplied. The following list includes only a fraction of the pamphlets that have been published by the Institute. Any other paper published by the Institute may be obtained for the price of $1, except those published in Volume XXXI, which are rare.

Jan 5, 1917

By S. Oglesby, A. L. Thomas

Until recently, probably the best means of sampling airborne dusts has been the impinger method. Dust-laden air is drawn into a sampling tube, and the particulate matters separated from the air and collected in the liquid in the impinger. A sample of the suspension is prepared on a slide and counted through a projection microscope. This method is simple and reliable, but it does suffer drawbacks. Since the collected particles must be counted visually, results of the dust count are not immediately available at the time the sample is taken. This seriously impedes studying the effectiveness of dust inhibitors, such as water sprays, or making adjustments in equipment. Greatest disadvantage of all, however, is the tedious task of counting particles in the sample. With the growing desirability of taking more samples, the effort involved in making these counts is a real factor in the cost of dust control. Finally, it is generally recognized that impinger dust counts can be related to health hazard only for specific kinds of dust and under similar conditions. This is because the rather complex mechanism of dust damage depends so much on size distribution of the dust. Counts determined by impinger samples cover a limited size range that does not necessarily corre-

Jan 1, 1960

By Sabert Oglesby, Albert L. Thomas

Until recently, probably the best means of sampling airborne dusts has been the impinger method. Dust-laden air is drawn into a sampling tube, and the particulate matters separated from the air and collected in the liquid in the impinger. A sample of the suspension is prepared on a slide and counted through a projection microscope. This method is simple and reliable, but it does suffer drawbacks. Since the collected particles must be counted visually, results of the dust count are taken. This seriously impedes studying the effectiveness of dust inhibitors, such as water sprays, or making adjustments in equipment. Greatest disadvantage of all, however, is the tedious task of counting particles in the sample. With the growing desirability of taking more samples, the effort involved in making these counts is a real factor in the cost of dust control. Finally, it is generally recognized that impinger dust counts can be related to health hazard only for specific kinds of dust and under similar conditions. This is because the rather complex mechanism of dust damage depends so much on size distribution of the dust. Counts determined by impinger samples cover a limited size range that does not necessarily correlate with retention by the lungs and upper respiratory tract.

Jan 3, 1959

By J. G. Richardson, F. M. Perkins

Results and procedures are pre-cented covering a laboratory investigation of the effect of rate of water advance on the displacement of oil from clean water-wet sands. The experiments included water floods at atmospheric pressure with and without gas present over a range of flow rates from reservoir rates to rates ten thousand-fold higher. Water floods were also conducted at various rates at elevated pressure with no gas present. Other tests were made at elevated pressures by forming a free gas saturation by evolution of gas from solution in the oil before water flooding. Recovery of oil was found to be independent of the rate of water advance with or without gas present and independent of the pressure level of the water flood. A dimensionally-scaled model of a reservoir composed of a thick uniform sand was used to study the effect of rate on the tendency of water to underrun the oil because of the greater density of the water. Another model was used to study the effect of rate on the tendency of water to channel down the more permeable sand in a stratified reservoir composed of sands of diffierent per-meability in intimate contact. The effect of the presence of gas on the flooding conformance was studied with both models. The results obtained using these simple models provide a basis for predicting behavior in more complicated systems. INTRODUCTION In spite of the great amount of research on the flow of fluids in porous rocks, there still exists some disagreement as to the influence of the rate of water advance on the displacement of oil by water flooding. Various investigators have found that increasing the rate of water injection would decrease, increase, or have no effect on recovery of oil. One reason for this disagreement has been a lack of understanding of the effects of the capillary forces which influence the results obtained in the laboratory at low rates with short columns. Other causes of the disagreement have undoubtedly been inconstancy and uncertainty of the wetting properties of the porous media studied, inaccurate saturation determinations, and in some instances conclusions based on insufficient data. Capillary forces are involved in the displacement of oil by water in two ways. On the microscopic scale, the capillary forces control the dis- tribution of oil and water in the pore spaces of the sand. The magnitude of these forces is governed by the preference of the sand to be wet by water, the pore sizes and geometrical shapes, and the interfacial tension between the water and oil. On the macroscopic scale, differences in saturation at the flooding "front" when water displaces oil result in capillary pressure gradients. These gradients cause water to flow preferentially ahead of the front. In short laboratory columns at low rates, the front can span the entire column length. Also, at the outflow boundary the preference of sand to be wetted by water results in retention of water and a high water saturation in the region of the outflow face. This effect is commonly called the boundary effect.' The capillary pressure gradients which complicate the interpretation of flooding performance of short laboratory columns at low rates of water advance become negligibly small under certain conditions. The conditions where capillary pressure gradients are negligible are in long, homogeneous reservoir sands,' at high rates of water advance in short laboratory columns,3 and at any rate in laboratory columns as the residual oil saturation is approached. Thus, laboratory water floods, conducted

Jan 1, 1958

By David W. Pasho

The success of a collector vehicle, designed to recover manganese nodules under the conditions which exist in deep ocean mine sites will in part be determined by the effectiveness of pick-up and running gear mechanisms. For the purpose of qualitative comparison, some specific aspects of seafloor interactions with various concepts are reviewed utilizing existing data on seafloor characteristics and running gear/tool interaction with soils.

Jan 1, 1976

By F. P. Schwarz, A. J. Erickson, S. M. Weber

The Mount Hope stockwork molybdenum deposit, Eureka County, Nevada, occurs In a small igneous cauldron complex 32 to 38 mybp in age. The deposit is characterized by alteration zones and mineralized shells symmetrically distributed around multiple intrusive. For samples from the 25000 meters of 1981-82 drilling, an appraisal of error in in-house sample preparation and in commercial assaying has been made. After splitting, drill core is crushed and reduced in volume (8: 1 at 10-mesh, 8: 1 at 70-mesh, 6: 1 at 200-mesh) to supply 25 grams of 200-mesh pulp for replicate analyses. A 0.5 g portion of the pulp 1s used for dissolution and atomic absorption analyses. Factors which initially generated unacceptable data variances have been minimized by planning, repeat analyses, introduction of standards, and routine monitoring. Assuming that error between replicate assays defines a Gaussian distribution with its average ideally equal to zero, precision (from preparation including core splitting and analysis of 8400 pairs of molybdenum samples) is on the order of ± 25%. The error distribution is not based. Accuracy is approximately 4% lower than absolute as determined by replicate assays of commercially prepared samples.

Jan 1, 1984

The earliest U. S. patent on a crushing machine was issued in 1830. The device incorporated the drop hammer principle later used in the famous stamp mill, whose history is so intimately linked with that of the golden age of American Mining. Eli Blake invented the first successful mechanical rock-breaker --the Blake jaw crusher--patented in 1858. The idea of his mechanical principle, the powerful-toggle linkage, was so sound that today the Blake -type jaw crusher is the standard by which all jaw crushers are judged. In 1881, Philetus Gates was granted a patent on a machine which included in its design all the essential features of the modern gyra tory crusher. For some years after these pioneer machines were developed, crushing requirements were quite simple. All underground mining and open-pit quarrying was done by hand with tonnages and rock sizes generally small. In the milling of precious metal ores, stamp mills were popular as the final reduction machine. The stamps were fed with an ore size readily produced by one break through small gyratory or jaw crushers. Even in large underground mining operations, there was no demand for large crushers; and increasing tonnage requirements were met by duplicating the small units. The Homestake gold mine in South Dakota was a good example, where in 19 15 twenty -two small Gates gyratory crushers were used to prepare the ore for the batteries of 2,500 stamps. Open pit mines and the introduction of the steam shovel created a demand for larger crushers, which led to the development of a gyratory with an 18 in. (457 mm) receiving opening. Up to this time, the jaw crusher had kept pace with the gyratory, both from the standpoint of receiving opening and capacity; but now the gyratory stepped into a 15-year lead with larger and larger sizes. This trend toward large primary crushers started just before the turn of the century, and in 1910 crushers with 48 in. (1.22 m) receiving openings were being built. About this time, the jaw crusher was revived in a great contribution to primary crushing by the introduction of the 84 in. by 60 in. (2. 13 by 1. 52 m) machine. This crusher was usually followed by a 24 in. (6 10 mm) opening gyratory crusher for secondary breakage, a system which reawakened the industry to the use of the jaw crusher as a primary breaker. It is interesting that although his machines never came into general use, Thomas A. Edison ranks as a pioneer in the development of the large primary breaker. Edis on reasoned that the recoverable electrical energy

Jan 1, 1978

By Paul Torrey

THE Northwestern Pennsylvania Oil Producers Association and the United States Geological Survey have cooperated in conducting a pre-liminary study of the character of the flood waters, the relationship of changes in concentration of the salts dissolved in these waters to ultimate flood-oil production, and the original association of oil and water in the Bradford field. Bradford has long been recognized as a dry-sand field. As a matter of fact, there had been little information available on the oil-field waters of northern Pennsylvania until this investigation was undertaken. THE BRADFORD SAND Practically all of the oil produced in the Bradford field comes from one horizon, generally known as the Third, or Bradford, sand. Originally, it was believed that the Bradford sand was equivalent to the Third sand of Venango County, Pennsylvania and the name "Third" unfortunately still persists, although shortly after the discovery of the Bradford pool Carll1 determined that there was a stratigraphic interval of approximately ;000 ft. between the two horizons. The Bradford sand, although varying considerably in thickness and lithology within local areas, is persistent throughout the field. It is of marine origin and, upon both paleontologi-cal and stratigraphic evidence, is regarded as a basal member of the Chemung formation.

Jan 1, 1927

By H. Kenworthy, R. B. Fisher, R. G. Knicherbocker, M. M. Fine

The progress made to date in the mineral dressing of complex Arkansas titanium ores is reported in this paper. Concentrates of rutile, a dioxide of titanium, were produced by treating a submarginal ore from the Magnet Cove Rutile Co., Inc., Magnet, Ark. The rutile recovery at present is 45 to 50 pct of the total TiO2, with the possibility of increased recovery with additional research. The work reported herein is part of a general study which will later include results of investigation of other titanium ore bodies in the Magnet, Ark., area. The fragile character of the rutile minerals, the softness of the gangue, the occurrence of pyrite and leucoxene, and the considerable proportion of extremely small size rutile in the presence of montmorillonite- and illite-type clays in the Magnet Cove open-pit mine are the important factors in the mineral dressing of this submarginal rutile ore. History The occurrence of titanium minerals in the Magnet Cove area of Arkansas was recognized as early as 1890, but it was not until about 1912 that any appreciable prospecting for the minerals was undertaken. At that time drilling was begun, a shaft was sunk, and several drifts were driven, but beneficiation to recover the titanium minerals was not attempted. The only successful mining and milling operation of the Magnet Cove rutile deposit was begun in 1932 by the Titanium Corp. of America and continued until 1942. The ore was washed by means of a rotary scrubber and then deslimed in a drag classifier. The discharge was ground in a rod mill, classified, and tabled to recover a rougher rutile concentrate, which was screen-sized and retabled on cleaner tables. The cleaner concentrates were given a reducing roast, screen-sized, and magnetically separated to produce a finished rutile concentrate. Most of the rutile produced during this period was sold abroad. In 1942, the Titanium Alloy Corp. of Arkansas (a subsidiary of the Titanium Alloy Manufacturing Co. of New York) purchased the property and rebuilt the mill. Subsequently, the plant and property were acquired by the Magnet Cove Rutile Co., Inc., of Little Rock, Ark., the present owners. Very little titanium has been produced since 1942. Although the Titanium Corp. activities yielded enough returns to allow continued operation for approximately 10 years, certain factors must be recognized. These are: (1) production of rutile in that period was during a low in the economic cycle which permitted low-cost operation on a small scale, and (2) a considerable portion of the production was above the water level and no drainage problems existed. Prior to this paper there has been no published report of any mineral-dressing investigation of the lower levels of the ore body. Reference is made in another paper1 to an earlier investigation of Magnet Cove rutile by the Rolla laboratory, in which it is stated that recoveries of 12 to 17 pct of the rutile were obtained. The present investigation was undertaken to improve the known milling processes and to provide adequate metallurgical information about the ore treatment. Titanium Technology The titanium mineral of primary interest in the present investigation was the titanium dioxide, rutile. Rutile is one of the industrial minerals whose annual consumption is relatively small but strategically important. The domestic production of rutile was 7100 tons in 1948. The imports of rutile in the same year were approximately 8000 tons.2 A major use of rutile is in the production of welding-rod coatings, for which a product containing a minimum of 92 pct titanic oxide is desired. Other constituents, such as lime, silica, and sulphur, must be held to a minimum, but hard-and-fast specifications for these elements cannot be drawn. It is necessary to incorporate the rutile in a welding-rod coating, make a sufficient number of test welds, and then determine the tensile strength of the weld metal in the as-welded and stress-relieved conditions. Such a test gives

Jan 1, 1950

[NOTE.-The following discussions of papers contained in this volume are printed without regard to order of succession. It has been impracticable to secure from the various parties, corrected reports of their contributions in time to effect any particular desired arrangement in this respect. The papers of Messrs. Pourcel, Osmond and Sauveur, were considered at Chicago together with others of cognate character ; and the whole discussion will be found in vol. xxiii., under the head, " Physics of Steel."]

Jan 1, 1894

By Raymond B. Ladoo

ABRASIVES include the substances, natural or artificial, that are used to grind, polish, abrade, scour, clean or otherwise remove solid material, usually by rubbing action but also by impact (sandblasting, for example). They do not include abrasive tools-for instance, lathe tools and files-or polishing agents such as waxes, which act by filling pores. Detergents and cleaners whose action is chemical rather than physical are omitted although some chemical action polishes and cleaners may also contain solid abrasives; for example, many metal polishes. GENERAL CONSIDERATIONS The most important physical properties of materials that qualify them for use as abrasives are hardness, toughness (or brittleness), grain shape and size, character of fracture or cleavage, purity or uniformity. For making bonded grain abrasives such as grinding wheels, additional important factors are stability under high heat and bonding characteristics of grain surfaces. The economic factors of cost and availability are always important. No one single property is paramount for any use. For some uses extreme hardness and toughness are needed, as in diamonds for drill bits; for others, the factors of greatest importance are hardness and ability to break down slowly under use, to develop fresh cutting edges when grains become worn-for example, in garnet for sandpaper, neither highly cleavable or friable grains nor extremely tough grains

Jan 1, 1949

By B. H. Sage, W. N. Lacey

The results of an extensive experimental program relating to the effectiveness of gravel screens have been correlated. The factors considered in some detail include gravel size and condition of packing, sand size and size distribution, fluid velocity, fluid viscosity, and thickness and arrangement of grave! screens. Good agreement between calculated values based upon probability considerations and experimental results relating to the influence of the thickness of the gravel screen was obtained. All of these factors are treated in the correlation in order that their influence may be taken into account in ascertaining the characteristics of an effective gravel screen for a particular set of conditions. The details of the experimental program are not given in the present paper but a description of generalized behavior and typical experimental results are recorded in graphic form. Introduction Gravel screens have been placed in water and oil wells for a number of yearsl,2,3 with the dual objective of increasing the productivity and decreasing the entrance of sand into the well bore. An understanding of the factors controlling the effectiveness of gravel screens in this connection is of industrial interest because it will lead to the proper selection of gravel. Some of the fundamental considerations involved in the migration of sand through a coarser body of porous materials were investigated by Coberly and Wagner4 and further experimental work has been carried out by Gumpertz.5 Apparently the pertinent phenomena are somewhat complex and are influenced by many variables. The present paper deals with the prediction of the behavior of gravel screens under the conditions encountered in practice but does not attempt to discuss the experimental methods or results that were obtained as a background and upon which the prediction is based. Influence OF Gravel Screens upon Productivity The use of a gravel screen may increase the productivity of a well by increasing its effective diameter, and this constitutes one of the objectives of its use. The permeability of most gravels and coarse sands that are employed in practice is so large compared to that of the sand in place that relatively little loss in production rate will arise from the use of material fine enough to cause the desired resistance to sand migration. For example, in Fig. I is depicted the approximate variation in the permeability of closely sized spherical gravels under the conditions of packing likely to be encountered in screens. The dotted lines indicate the variation that might be found because of differences in packing. It should be realized that the permeability is not a single-valued function of the average grain diameter but is related to a large number of factors, including the size, the size distribution and the shapes of the particles. However, Fig. I does permit a rough estimation of the permeability of closely sized spherical gravels and shows that the permeability with even the smaller particles is very large compared to that of most petroleum production horizons.

Jan 1, 1942

By W. N. Lacey, B. H. Sage

The results of an extensive experimental program relating to the effectiveness of gravel screens have been correlated. The factors considered in some detail include gravel size and condition of packing, sand size and size distribution, fluid velocity, fluid viscosity, and thickness and arrangement of grave! screens. Good agreement between calculated values based upon probability considerations and experimental results relating to the influence of the thickness of the gravel screen was obtained. All of these factors are treated in the correlation in order that their influence may be taken into account in ascertaining the characteristics of an effective gravel screen for a particular set of conditions. The details of the experimental program are not given in the present paper but a description of generalized behavior and typical experimental results are recorded in graphic form. Introduction Gravel screens have been placed in water and oil wells for a number of yearsl,2,3 with the dual objective of increasing the productivity and decreasing the entrance of sand into the well bore. An understanding of the factors controlling the effectiveness of gravel screens in this connection is of industrial interest because it will lead to the proper selection of gravel. Some of the fundamental considerations involved in the migration of sand through a coarser body of porous materials were investigated by Coberly and Wagner4 and further experimental work has been carried out by Gumpertz.5 Apparently the pertinent phenomena are somewhat complex and are influenced by many variables. The present paper deals with the prediction of the behavior of gravel screens under the conditions encountered in practice but does not attempt to discuss the experimental methods or results that were obtained as a background and upon which the prediction is based. Influence OF Gravel Screens upon Productivity The use of a gravel screen may increase the productivity of a well by increasing its effective diameter, and this constitutes one of the objectives of its use. The permeability of most gravels and coarse sands that are employed in practice is so large compared to that of the sand in place that relatively little loss in production rate will arise from the use of material fine enough to cause the desired resistance to sand migration. For example, in Fig. I is depicted the approximate variation in the permeability of closely sized spherical gravels under the conditions of packing likely to be encountered in screens. The dotted lines indicate the variation that might be found because of differences in packing. It should be realized that the permeability is not a single-valued function of the average grain diameter but is related to a large number of factors, including the size, the size distribution and the shapes of the particles. However, Fig. I does permit a rough estimation of the permeability of closely sized spherical gravels and shows that the permeability with even the smaller particles is very large compared to that of most petroleum production horizons.

Jan 1, 1942

By T. E. Wayland

The general geology and mineralogy of bentonite, including pertinent technological details of clay minerals in the montmorillonite group, are summarized. Worldwide occurrences of bentonite deposits are reviewed, with emphasis on geologic methods and economic principles of evaluation. Active mining districts are described and areas with potential for current and future development are assessed. The production history of bentonite, principal producers, major consumers, and indicated trends are noted; also attention is directed to the hundreds of minor industrial uses of this versatile material, ranging from the manufacture of (A)cid neutralizers to (Z)eolite water softeners. Recent significant results of both basic and applied research are reported, with suggested lines of investigation for current and near-future consideration.

Jan 1, 1972

By Fred P. Dewey

Although coke is the acknowledged metallurgical fuel, and has been extensively used in this country for more than thirty years, yet the facts on record in regard to its physical properties are exceedingly meagre; and this is also true, but in a less degree, of its chemical composition. An investigation is being carried on in the National Museum which is intended to supply, so far as may be, this deficiency, and through the kindness of Professor Baird, Director of the Museum, I am permitted to present to the Institute a summary of a portion of the results already obtained. So far as I am aware, the credit for the first systematic investigation of the physical properties of coke belongs to Mr. John Fulton, Mining Engineer of Cambria Iron Co. The results of this investigation have been published in Report L, Second Geological Survey, Pennsylvania, 1875, and in a pamphlet setting forth the advantages of the Connellsville coke, the latter published also by the " Virginias"* His results are not altogether free from experimental errors, and the assumption that "the specific gravities of coke and water are very nearly alike "- is scarcely warranted. It has seemed to me, therefore, desirable to make an independent investigation of the physical properties of coke on a plan somewhat different from that adopted by Mr. Fulton. This is the investigation now being carried on at the National Museum.

Jan 1, 1884

By Francis B. Foley

THE casting of steel in large molds brings into play all of the undesirable effects that result inevitably from slow cooling. The origin of the molten metal, whether basic or acid open hearth or electric furnace, has little if anything to do with the phenomena involved. If the quantity of molten metal to be cast in a single mold is large enough, there is very little one can do about it-the metal will cool so slowly that 'nothing one can do, other than to provide as good feeding as practicable from an adequate reservoir of metal in the sink head, will be of any avail. Recently we have had occasion to cast a 108-in. octagon ingot weighing 545,700 lb, necessitating the combining of metal from three 100-ton open-hearth heats. This is one of the largest ingots ever made. The body of the ingot weighed 448,800 lb, which includes a bottom pool of about 7500 lb of metal, and the sink-head weight was 96,900 lb, or about 18 pct of the total weight.

Jan 1, 1947

By James P. Kimball

BY the term weathering of coal is meant the process of deterioration to which under various circumstances it may be exposed at ordinary temperatures, both from outward agencies on the one hand, and on the other hand from its own constitutional qualities. This process involves along with some minor qualitative changes certain quantitative changes resulting in a gradual and limited reduction in the quantity of the organic elements, and relatively a corresponding increase of its inorganic or mineral constituents as represented by its ashes, and often in an increase of the absolute weight of the coal. In common with many mineral substances, coal absorbs oxygen

Jan 1, 1880

By James P. Kimball

By the term weathering of coal is meant the process of deterioration to which under various circi~mstances it may be exposed at ordinary temperatures, both from outward agencies on the one hand, and on the other hand from its own constitutional qualities. This process involves along with some minor qualitative changes certain quantitative changes resulting in a gradual and limited reduction in the quantity of the organic elements, and relatively a corresponding increase of its inorganic or mineral constituents as represented by its ashes, and often in an increase of the absolute weight of the coal. In common with many mineral substances, coal absorbs oxygen

Jan 1, 1880

By H. R. Wuthrich

The Metallgesellschaft AG decided in late 1965 to build an Electrolytic Zinc Plant at Datteln (W. Germany). Lurgi-Chemie was entrusted with the engineering and erection of the entire plant. Ground was broken in February 1967 and the operation was started on August 1st, 1968. The new Electrolytic Zinc Plant was designed to produce a minimum of 100,000 metric tons of special high grade zinc and 200,000 metric tons of sulphuric acid. Concentrates from Meggen (W. Germany) and mainly Timmins (Canada) are roasted in two turbulent layer roasters. The sulfur dioxide containing gases are converted in a "Bayer double catalysis unit" to sulfuric acid. The calcine is leached batch wise, the leach residue separated from the pregnant solution by counter-current thickeners and drum filters. For maintaining the sulfate balance a modified jarosite leach is being used. After a two step purification the neutral solution is mixed with spent electrolyte and cooled in unpacked atmospheric cooling towers. Three electrical circuits are supplying the power to the tankhouse, each rated at 30,000 amperes. With a maximum current density of 750 amperes per square meter and a stripping cycle of 24 hours, an average current efficiency of 90 percent is obtained. Cathodes are melted in one induction furnace and cast into shapes, or alloyed with aluminum and copper for die-cast metal.

Jan 1, 1970