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By Stuart St. Clair

IN view of the great interest shown in the oil possibilities of Kentucky, one is impressed with the paucity of reliable literature on the oil fields of the state. A few brief reports by the Federal and State Geological Surveys are about the only reliable data available. When the estimated production figures, for 1918, are published by the U. S. Geological Survey, they will show a revival of the oil industry in the Blue Grass State during the past half decade. There will also be an increase in the production for 1919 and 1920, at least. Although as an oil-producing state Kentucky is small, compared with sonic of the other oil states, the present production and the area of undrilled proved territory is large enough to classify it as one of the important oil states of the Union. This paper will be confined to the Irvine District and the immediately adjoining areas which have been prospected with varying success. The Corniferous limestone or Irvine sand is the oil-producing formation in the area discussed.

Jan 7, 1919

By T. L. Joseph

THE committee appointed to investigate the application of oxygenated air to the blast' furnace believes, after a careful study of the problem, that this enriched air will increase hearth temperature, tonnage, flexibility of operation, and quality of pig iron made, and that fuel consumption will be decreased. These improvements are supported by theoretical evidence; but a practical trial of the process is necessary to establish more definitely the magnitude of benefits realized. The commercial application, however, may profitably be preceded by a test on a smaller scale. A small furnace will, in general, respond to the enriched air in the same way as a commercial furnace and the magnitude of the benefits to be gained from varying additions of oxygen can be fairly well established at relatively little expense. A new experimental furnace, being built jointly by the Bureau of Mines and the University of Minnesota, at Minneapolis, will have a capacity of about 6 tons and will riot require more than 700 cu. ft. of natural air per minute. Its hearth is 36 in. in diameter and its height about 32 ft. Enough oxygen to enrich the blast to the extent recommended by the committee can be obtained from a small oxygen unit. It might even be cheaper to perform preliminary experiments with tanks of oxygen obtained from regular, dealers. A procedure in making the test that suggests itself is to start with operation on normal air; then to use blast, enriched in several steps. Systematic temperature measurements of the tuyeres, slag, and metal would reveal any changes in hearth temperature. When these changes become large enough, the burden may be gradually increased to just within the breaking point and the furnace brought back to normal, if possible, by the addition of oxygen. Such a test would show what might be expected in the way of a decrease in fuel consumption and the time taken to "straighten up" the furnace by means of oxygen. The new furnace at Minneapolis is so equipped that the furnace process can be observed from the stock line to the iron notch. We have been taking gas samples at various elevations in the furnace to study combustibility of the fuel and the reducing power of the gas. If either of these is affected by removing inert nitrogen, the change can easily be measured.

Jan 11, 1924

By D. Geoffry Minnes, Ray Blair, Stanley J. LeFond

Nepheline syenite is a silica deficient crystal-line rock consisting of albite and microcline feldspars and nepheline, together with varying but small amounts of mafic silicates and other accessory minerals. Nepheline-bearing rocks are widely distributed around the world but only in Canada, Norway, the Union of Soviet Socialist Republics, and the United States are deposits worked commercially, Because of its low melting point and fluxing ability, nepheline syenite was investigated in the early 1900s by many students of glass and ceramics. Although the nepheline syenite deposits in Methuen Township, Ont., Canada, were discovered as early as 1897 it wasn't until 1935 that the first mill was erected to produce nepheline syenite products. In Canada, nepheline syenite deposits are worked by Indusmin Ltd. and International Minerals and Chemical Corp. (Canada) Ltd. who have combined production capacity in excess of 1800 stpd. Between 1935 and 1972 seven million tons valued at $78 million were produced from the Methuen Township deposits. In Norway, the Norsk Nefelin Div. of Elkem Spigerverket has produced nepheline syenite from a deposit on Stjernöy Island in western Finland since early 1960. Production has increased from 8 kt in 1961 to over 200 kt in 1980. Nepheline syenite has been under investigation in the Union of Soviet Socialist Republics (USSR) since at least 1928. In 1951 the first commercial alumina works was brought on stream at Volkhov, near Leningrad, utilizing nepheline concentrates from the Kola peninsula as mill feed. Since then two others have been completed and more are planned. Large quantities of portland cement, sodium carbonate, and potassium carbonate are produced in conjunction with the alumina. A material called nepheline syenite, but actually a pulaskite, is produced in Pulaski County, Arkansas, by the McGeorge Construction Co. for construction aggregates and by the 3M Co. for roofing granules. The Dome Fill Co. purchases the fines and uses them in the preparation of enclosed construction fill. Production is over 2,000,000 stpy. Chap. 16 on "Feldspar, Nepheline Syenite, and Aplite" in the 3rd ed. of Industrial Minerals and Rocks (Castle and Gillson, 1960) and Nepheline Syenite Deposits of Southern Ontario (Hewitt, 1960) contain excellent accounts of earlier commercial development of nepheline syenite as a glass and ceramic material. As in the 4th ed., this chapter deals mostly with the period since 1960 and with matters not previously reported in detail. An English monograph on Nepheline-Syenite and Phonolite (Allen et al., 1968) is a complete survey, at the time, of nepheline syenite which, with its very complete list of references, is an excellent source book. End Uses Nepheline syenite from the Canadian and Norwegian producers finds use primarily in the manufacture of glass and ceramics. One producer also makes several grades of nephellne syenite that are useful as extender pigments and fillers in paint, plastics, and rubber. In the Soviet Union nepheline is used in increasing quantities in the manufacture of alumina, alkali carbonates, and portland cement and to a lesser degree it is used in the manufacture of colored container glass.

Jan 1, 1983

By Henry M. Howe

The brilliant and very original matter in Professor Jeffries' discussion† should rank not only as an independent paper, but as a most important one. In particular, the explanation which it gives of the remarkable Sauveur phenomenon, over which so many of us have puzzled long and hard, is so clear, complete, and cogent as to go far toward establishing Professor Jeffries' hypothesis. The very leatures of Professor Sauveur's photographs which fit this hypothesis so exactly are reproduced in Chap-pell's photographs of steel coarsened under somewhat different conditions.' The ideas developed by these discoveries are so novel that convenicnce of language seems to call for new conventional terms for expressing them. In what follows here I propose certain terms for this end, for criticism and improvement, and I attempt to generalize from Professor Jeffries' hypotheses. Generally speaking, a given set of grains which undergo no growth in the cold will, when the temperature is raised progrcssively, start to grow on reaching a certain temperature, and will continue growing at all higher temperatures. The "germinative" temperature is that at which growth begins, quite as the conditions which cause a seed to grow are "germinative." We have then an inert temperature range below the germinative temperature, and a growth range above it, the germinative temperature being the limit between these two ranges. So, too, a germinant grain is one which is at its germinative temperature, and hence beginning to grow, while inert grains are those below their own germinative temperature, and the term "growing grains" includes those which are germinant and those which are above their germinative temperature. These last could be called " supergerminant" if the distinction should be needed. "Germinative temperature" seems better than "critical temperature

Jan 1, 1917

By John W. Chang

Introduction Automatic control of primary ball mill circuits has received much attention over the past decade, primarily because its advantages ultimately can be translated into economic terms. Apart from such obvious benefits as improved product quality, increased throughput, and more stable operation, less direct benefits such as easier operation, more orderly maintenance scheduling, and timely management reports all can be realized with the application of modern automatic process control equipment and techniques. Software configurable digital computer-based control systems offer ease of change in control strategies. Occasional control strategy changes are necessary whenever control objectives change or circuit modifications occur. The dependency of control strategies on control objectives and circuit equipment to effect optimal circuit operation is an important, but often neglected issue. Because of the potential for even better control, research and development work continues. [See (Ulsoy & Sastry, 1981) and (Hulbert & Braae, 1981).] Some of the possibilities are discussed later in this presentation. A few preliminary remarks may be in order concerning the relationships among control objectives, control strategies, and circuit equipment. Generally accepted control objectives for primary ball mill circuits include: 1. Maintaining a desired percent solids in the mill. 2. Maintaining a desired measure of particle size distribution at the cyclone overflow. 3. Maximizing throughput. Control Objective I is a requirement for proper operation of the ball mill, especially if it is a grate mill. It concerns smooth movement of material through the mill. Control Objective 2 is a product specification - one of the requirements for proper flotation operation. Control Objective 3, an expression of the desire to get the most out of the circuit, is the easiest to evaluate in economic terms. It assumes that the processes downstream

Jan 1, 1982

By D. L. Katz

The Oklahoma City Wilcox sand, discovered on March 26, 1930, has produced 394 million barrels of crude oil and 819 billion cubic feet of natural gas as of July I, 1941. The 100,000-bbl. wells, pressures of 2600 lb. per sq. in., and flows of "Wilcox" sand caused exciting moments in the early life of the field. Today the reservoir is substantially at atmospheric pressure and produccs 75,000 bbl. of crude oil daily through 466 pumping wells. Early estimates of the initial crude-oil content of the "Wilcox" sand1 indicated that about 600 million barrels of crude oil would remain after the pumping wells ceased to produce economically. The Oklahoma City Wilcox Secondary Recovery Association was organized in March 1939, to study the possibilities of recovering a portion of this oil. Only a very brief summary of the information available can be presented in a paper of this nature. Some simplifications and generalizations are necessary to give the over-all picture in SO short a space and statements made may not apply to a specific well or small area. Since the area under consideration by the Association is that north of the south line of section 22-11-3, some information will be presented for areas A, B, C, 1, 2, 3 and part of 4 of Fig. 2, and some will be for the entire Wilcox zone west of the fault. This paper is essentially an abstract of an engineering report made by A. D. Small, B. T. Murphree, M. C. Sons and the author for the Oklahoma City Wilcox Secondary Recovery Association on Sept. 5, 1940. Some information is taken from a report to the Association by C. V. Sidwell on March I, 1940, and some data are from a recent report by A. D. Small. It gives a brief history of the Wilcox zone, estimates of the initial oil contents of the reservoir, present conditions in the reservoir, and probable results from several programs of "secondary recovery." History of Wilcox Zone The Wilcox sand lies on the flank of the general structure, as shown by cross section of Fig. I2,3,4 and areal map of Fig. 2. The sand is of Ordovician age and is composed of well assorted, rounded sand grains with no apparent cementing material. The loose texture of the sand is shown by the enormous quantities of sand production from the wells and from the soft cores. The productive sand varies from zero thickness on the east to 220 ft. maximum and to zero thickness on the west because of water. The development of the pool4 as dependent upon drilling restrictions within the city limits, which accounts for the spacing of drilling operations listed in Table I by years. In 1931, areas I through 7 of Fig. 2 were open for drilling with the exception of some west-edge properties, and all wells drilled before Feb. I, 1935, were in this portion of the field. Nearly all wells drilled from 1933 to 1037 were in areas A, B and C. Since 1939, the newly drilled wells have gradually enlarged the producing area toward the west in the northern portion.

Jan 1, 1942

By D. L. Katz

The Oklahoma City Wilcox sand, discovered on March 26, 1930, has produced 394 million barrels of crude oil and 819 billion cubic feet of natural gas as of July I, 1941. The 100,000-bbl. wells, pressures of 2600 lb. per sq. in., and flows of "Wilcox" sand caused exciting moments in the early life of the field. Today the reservoir is substantially at atmospheric pressure and produccs 75,000 bbl. of crude oil daily through 466 pumping wells. Early estimates of the initial crude-oil content of the "Wilcox" sand1 indicated that about 600 million barrels of crude oil would remain after the pumping wells ceased to produce economically. The Oklahoma City Wilcox Secondary Recovery Association was organized in March 1939, to study the possibilities of recovering a portion of this oil. Only a very brief summary of the information available can be presented in a paper of this nature. Some simplifications and generalizations are necessary to give the over-all picture in SO short a space and statements made may not apply to a specific well or small area. Since the area under consideration by the Association is that north of the south line of section 22-11-3, some information will be presented for areas A, B, C, 1, 2, 3 and part of 4 of Fig. 2, and some will be for the entire Wilcox zone west of the fault. This paper is essentially an abstract of an engineering report made by A. D. Small, B. T. Murphree, M. C. Sons and the author for the Oklahoma City Wilcox Secondary Recovery Association on Sept. 5, 1940. Some information is taken from a report to the Association by C. V. Sidwell on March I, 1940, and some data are from a recent report by A. D. Small. It gives a brief history of the Wilcox zone, estimates of the initial oil contents of the reservoir, present conditions in the reservoir, and probable results from several programs of "secondary recovery." History of Wilcox Zone The Wilcox sand lies on the flank of the general structure, as shown by cross section of Fig. I2,3,4 and areal map of Fig. 2. The sand is of Ordovician age and is composed of well assorted, rounded sand grains with no apparent cementing material. The loose texture of the sand is shown by the enormous quantities of sand production from the wells and from the soft cores. The productive sand varies from zero thickness on the east to 220 ft. maximum and to zero thickness on the west because of water. The development of the pool4 as dependent upon drilling restrictions within the city limits, which accounts for the spacing of drilling operations listed in Table I by years. In 1931, areas I through 7 of Fig. 2 were open for drilling with the exception of some west-edge properties, and all wells drilled before Feb. I, 1935, were in this portion of the field. Nearly all wells drilled from 1933 to 1037 were in areas A, B and C. Since 1939, the newly drilled wells have gradually enlarged the producing area toward the west in the northern portion.

Jan 1, 1942

By Donald L. Katz

THE Oklahoma City Wilcox sand, discovered on March 26, 1930, has produced 394 million barrels of crude oil and 819 billion cubic feet of natural gas as of July 1, 1941. The 100,000-bbl. wells, pressures of 2600 lb. per sq. in., and flows of "Wilcox" sand caused exciting moments in the early life of the field. Today the reservoir is substantially at atmospheric pressure and produces 75,000 bbl. of crude oil daily through 466 pumping wells. Early estimates of the initial crude-oil content of the "Wilcox" sand' indicated that about 600 million barrels of crude oil would remain after the pumping wells ceased to produce economically. The Oklahoma City Wilcox Secondary Recovery Association was organized in March 1939, to study the possibilities of recovering a portion of this oil. Only a very brief summary of the information available can be presented in a paper of this nature. Some simplification and generalizations are necessary to give the over-all picture in so short a space and statements made may not apply to a specific well or small area. Since the area under consideration by the Association is that north of the south line of section 22-11-3, some information will be presented for areas A, B, C, r, 2, 3 and part of 4 of Fig. 2, and some will be for the entire Wilcox zone west of the fault. This paper is essentially an abstract of an engineering report made by A. D. Small, B. T. Murphree, M. C. Sons and the author for the Oklahoma City. Wilcox Secondary Recovery Association on Sept. 5;.1940. Some information is taken from a report to the Association by C. V. Sidwell on March 1, 1940, and some data are from a recent report by A. D. Small. It gives a brief history of the Wilcox zone, estimates of the initial oil contents of the reservoir, present conditions in the reservoir, and probable results from several programs of "secondary recovery." HISTORY OF WILCOX ZONE The Wilcox sand lies on the flank of the general structure, as shown by cross section of Fig. 12.1 .4 and areal map of Fig. 2. The sand is of Ordivician age and is composed of well assorted, rounded' sand grains with no apparent cementing material. The loose texture of the sand is shown by the enormous quantities of sand production from the wells and from the soft cores. The productive sand varies from zero thickness on the east to 220 ft. maximum and to zero thickness on the west because of water. The development of the pool4 was dependent upon drilling restrictions within the city limits, which accounts for the spacing of drilling operations listed in Table I by years. In 1931, areas I through 7 of Fig. 2 were open for drilling with the exception of some west-edge properties, and all wells drilled before Feb. I, 1935, were in this portion of the field. Nearly all wells drilled from 1933 to 1937 were in areas A, B and C. Since 1939, the newly drilled wells have gradually enlarged the producing area toward the west in the northern portion.

Jan 1, 1941

By S. R. Mitchell, M. Weissman, J. H. Brown

It has been demonstrated that for fine grinding operations, the energy input (E) and the product size modulus (k) are related by an equation of the form E = Ak1-n (1) where "A " and "n" are constants.(1) Also, it was suggested that "A" is determined by the comminuting device and that "n" depends primarily on the rock. It was the purpose of this investigation to study these constants by determining the form of an energy-size reduction relationship over an extreme range of energy inputs, and at the same time, to evaluate the minimum particle size produced during grinding. The comminution system consisted of a stainless steel laboratory ball mill in which quartz was ground at 60% solids for times ranging from 1 minute to 700 hours. The mill which measured 10" diameter by 12" long was loaded with about 60 pounds of balls ranging in diameter from 3/8" to 1-1/8" and was driven at 55 r.p.m. Quartz was selected for the tests because it is a brittle material for which size distribution data were expected to show a constant distribution coefficient regardless of product size.(1) This permitted specification of product size by a size modulus alone. The quantities measured were the time of grind (measure of energy input) and the specific surfaces of the products. Since no accurate method is available yet for determining particle size directly in the very fine size ranges specific surface data were used for this purpose. The relationship between these two quantities may be expressed as where Cis a constant which includes a shape factor, p is the specific gravity of the solid,_S is the specific surface and D is an equivalent particle diameter. For a material in which the distribution coefficient does not change with size the term (l/S) may be substituted for k in equation L if the proportionality constant "A" is changed correspondingly. This substitution was made in this work but in addition, screen analyses were made on several products to verify the equivalence of the two methods of size specification. EXPERIMENTAL DETAIL QUARTZ Quartz from two sources was tested. One series of tests was made on a clear, high purity crystalline quartz from Brazil and Arkansas, and another series was run on massive quartz fromNewHampshire. Grinding charges of the high purity material consisted of 2000 gram samples of -3-8 mesh particles, while the charges of the New Hampshire quartz were 500 gram samples of a -35+48 mesh screen fraction. The difference in the sizes of these two series of charges was not significant in view of the extreme size reduction accomplished, and the New Hampshire samples were smaller to permit ginding to finer sizes in shorter times than required for 2000 gram lots. SAMPLING AND ANALYSIS Separate charges were ground for all tests in which the grinding times were less than one hour and for all tests on New Hampshire quartz since these products were difficult to sample accurately without affecting the entire charge. During the long time grinding tests the mill was

Jan 1, 1961

By AIME AIME

A new Index of the Transactions, Volumes I. to XXXV., is now being prepared, and will probably be ready for distribution during the coming summer. The Index will be about the size of the average volume of the Transactions, and will be bound in cloth and in half morocco. The price of the cloth-bound copy is $5, expressage prepaid. Half morocco binding will cost $1 extra. It is very desirable that all who wish to purchase this Index will notify the Secretary's office promptly, sending a check, money-order or draft, made payable to the American Institute of Mining Engineers.

May 1, 1907

By W. O. Philbrook, K. Natesan

The oxidation kinetics of spherical pellets of zinc sulfide made from Santander concentrates were studied using a thermogravimetric technique. The experiments covered a temperature range-. of 740" to 102O°C, 0-N mixtures varying from 20 to LOO pct O2, and pellet diameters between 0.4 and 1.6 cm. Mathematical models were formulated to Predict the reaction rate on the assumption that a single transport or interface reaction step was rate -controlling. Analysis of the data indicated that the process of oxidation was predominantly controlled by transport through the zinc oxide reaction-Product layer. ROASTING processes, which are reactions between solids and gases, are very important because they are employed in the production of a number of basic metals. These processes are highly complicated, and one needs to consider the transport phenomena of heat and mass between the solids and gases in addition to the kinetics of various chemical reactions involved. Because of such complications there is a lack of knowledge concerning the rate-limiting factors, which may strongly depend on temperature, particle size, gas composition, and solid structure. The oxidation of zinc sulfide, which is of commercial importance in zinc production, falls into this class of reactions. The major goal of this work was to elucidate the roles played by different process variables, such as reaction temperature, gas composition, pellet size, and pellet porosity, on the kinetics of oxidation of single pellets of zinc sulfide. Roasting of zinc sulfide single particles has been a subject of both experimental and theoretical investigations.&apos;-&apos; The reaction is exothermic and may be considered to be irreversible. Such a reaction has been found to proceed in a topochemical manner. In other words, as the reaction proceeds, a progressively thicker outer shell of zinc oxide is formed, while the inner core of unreacted sulfide decreases. It has been found experimentally, both in the present work and in the previous investigations,1-9 that the particle retains its original dimensions and the process requires transport of gaseous oxygen across the porous product layer for continued reaction. The reaction may be represented by ZnS(s) + 3/2 O2(g) = ZnO(s) + SO2(g) [1] The solid product considered here is only zinc oxide, since the diffraction patterns of zinc sulfide pellets oxidized partially at &apos;798" and 960°C showed K. NATESAN, Junior Member AIME, formerly St. Joseph Lead Fellow, Department of Metallurgy and Materials Science, Carnegie-Mellon University, Pittsburgh, Pa., is now at Argonne National Laboratory, Argonne, Ill. W. 0. PHILBROOK, Member AIME, is Professor of Metallurgy and Materials Science, Carnegie-Mellon University. This paper is based on a them submitted by K. NATESAN in partial fulfillment of the requirements for the Ph.D. degree in Metallurgy and Materials Science at Carnegie-Mellon University. Manuscript submitted December 2, 1968. EMD lines corresponding to original zinc sulfide and the newly formed zinc oxide. OXIDATION MODEL The generalized model for gaseous oxidation of zinc sulfide is illustrated in Fig. 1. This depicts a partially oxidized sphere of zinc sulfide in a gas stream surrounded by a laminar film of gas. The spherical sample of zinc sulfide of unchanging external radius r0 is suspended in a flowing gas stream of total pressure PT and composition specified by the partial pressures of the individual components. Partial pressures of the gaseous species in the bulk gas phase, at the exterior surface of the pellet, at the ZnS/ZnO interface, and at equilibrium for Reaction [I] are identified by the superscripts b, o, i, and eq, respectively. The overall reaction involves the following ~te~s:&apos;~&apos;~&apos; Step 1. Transfer of reactant gas (oxygen) from the bulk gas stream across the gas boundary layer to the exterior surface of the pellet and the reverse transfer of the product gas (sulfur dioxide). Step 2. Diffusion and bulk flow of oxygen from the pellet surface through the product shell (ZnO) onto the ZnS/ZnO interface and the reverse transfer of sulfur dioxide. Step 3. Chemical reaction at the interface, which results in consumption of oxygen gas and generation of sulfur dioxide gas and heat; at the same time the _________ PARTICLE SURFACE / x^^^^n^X / MOVING INTERFACE core-----/ sJSNxy " /T^T^02 \ V\V$\ ^NWX/ "*/— GAS BOUNDARY x. \\ZnO SHELLV/ / \^ . / &apos; ^ BULK GAS --------N_______ _____,------p£ w \ P« / (f> \ / a \ <i) / <----------------- _(o) ^^--------------(b) °- pso, pso2 ro ri 0 ri ro RADIAL POSITION Fig. 1—Generalized model for oxidation of a sphere of zinc sulfide.

Jan 1, 1970

By F. W. McNair

WITHIN the last twenty-five or thirty years the actual operations of the great mining industry have passed almost wholly under the charge of men trained in the technical colleges. It follows that the industry is profoundly influenced for good or ill by the character of the training which the college graduate receives, and the relations existing between the industry and the colleges. This fact seems to be generally recognized, as evidenced, for example, by the existence of a Committee on Technical Education created some two or three years ago by the Mining and Metallurgical Society of America. In 1921 this committee rendered a very able and. extremely well poised reports of technical education as applied to the prospective mining engineer. It deserves the attention of every one interested in the effectiveness of engineering training. That the importance of the relation between the mining industry and the engineering colleges is recog-nized is evidenced also by the mass of criticism, usually adverse, which is proffered to and often hurled at the colleges by those in the industry. The man inn the field sometimes goes so far as to say that engineering educa-tion is hopelessly inefficient and its product worthless, while the college worker sometimes complains that the demands of the industrialist are too numerous and conflicting to be met, and adds that they would&apos; best be ignored. Between these extremes, there seems to be a general consensus of opinion that the training of the would-be engineer can be, and. ought to be, made much better than it now is.

Jan 4, 1923

By John C. Kleiber, George M. Meisel

From time to time since the initial installation of an experimental flotation section in 1940, Permanente Cement Co. has made efforts to beneficiate the low-grade limestone fraction which occurs in its deposits at Permanente, Calif. The encouraging results outlined in this article are the result of Permanente&apos;s latest effort. THE PERMANENTE LIMESTONE AND THE REASON FOR ITS BENEFICIATION The Permanente deposit is a sheet of Calera limestone over 700 ft thick lying within the Franciscan sediments of the San Francisco peninsula. Limestone suitable for cement manufacture underlies, overlies, and is interbedded with low-grade limestone and chert. Andesite intrusions are found as a secondary gangue. The limestone is identified as follows:

Jan 3, 1964

By Milton E. Wadsworth, Edward M. Eyring

Better understanding of solid surfaces and their associated adsorption products is of both academic and practical value. The study of detergents and their behavior in cleaning surfaces is fundamentally related to the nature of the products adsorbed and their ability to compete for certain surfaces. Similarly in flotation, the nature of the adsorbate before and after adsorption is basic to clear understanding of the process. The recently developed pellet technique employing infrared spectroscopy provides a powerful tool for the study of solid surfaces. Absorption bands, which are infrared-active, may be observed for adsorbed products. Also any changes in the surface substrate that occur as a result of adsorption may be detected by means of differential spectra

May 1, 1956

The Library is a cooperative activity of the American Institute of Mining and Metallurgical Engineers, the American Society of Civil Engineers, the American Institute of Electrical Engineers and the American Society of Mechanical Engineers. It is administered as a public reference library of engineering and the allied sciences. It contains 133,000 volumes and pamphlets, 6700 maps and receives currently most of the important periodicals in its field. In order to place the resources of the Library at the disposal of those unable to visit it in person, the Library is prepared to furnish lists of references to engineering subjects, copies or translations of articles, and similar assistance. Charges sufficient to cover the cost of this work are made.

Jan 1, 1933

By F. Peter

Technical progress takes place in two directions: the improvement of methods, affecting the quality of the product; and increase in the economy of operations, affecting its cost. In the iron-industry, practice is pretty well settled, and revolutionary changes of method are, for the present, not to be expected. Hence, in this industry, the principal endeavor is to reduce costs by the use of labor-saving inventions, such as the machines brought into use during the last decade. But it is not alone necessary to reduce the labor-cost; complete economy requires also a saving in raw material. Under this head we may rank the coal employed as metallurgical fuel; and it follows that progress includes the economic use of fuel, so managed as not to injure quality of product. In the present paper it will be shown how, by suitable utilization of the heat from the furnace, a large portion of it may be made available for other purposes. Such utilization of waste-gases is important in all industries which employ furnaces (especially heating-and smelting-furnaces); and in the first rank of these stand the iron-, glass-, and porcelain-manufactures. The following pages are devoted chiefly to the waste-gases of smelting-works, and especially to those reverberatory-furnace gases which are not combustible.&apos; The object of metallurgical furnaces is either to fuse the material charged or to bring it to a high temperature required for further mechanical manipulation. Leaving out of consideration for the present the reverberatory fusion-furnaces, we have to do with the heating-furnaces employed in connection with rolls, hammers, or hydraulic presses. The temperature to which the material must be

Jan 1, 1914

By Thomas M. Plouf

Flotation, as we know it today, is a physiochemical method of concentrating finely ground ores. The process involves chemical treatment of an ore pulp to create conditions favorable for the attachment of certain mineral particles to air bubbles which are carried to the surface of the ore pulp for removal. Frother reagents, combined with air and the agitation mechanism, produce the effective bubbles in a flotation cell. A method of analysis is presented to evaluate the effect of frother reductions and additions on a bank of flotation cells, and to economically determine if and to what extent frother reductions and additions are justified. Comparative evaluations of different frother systems, as well as the amount of frother used in a given flotation machine, cannot be made on the frother cost alone. An indepth study must be made to evaluate any given frother as applied to a particular ore body. The recovery of a given mineral is as dependent on the amount of frother as on the type of frother used. An actual case study follows in which the amount of frother required by two different flotation machines was used to make a decision as to which unit performed more efficiently based on costs. This same method may be used to evaluate new frothers as well as to determine if a larger frother addition is advisable.

Jan 11, 1975

By William E. Ford, Edward Salisbury Dana

This section includes the common calcium titano-silicate, Tiianite; also a number of silicates which contain titanium, but whose relations are not altogether clear; further the titanate, Perovskite, and niobo-titanate, Dysanalyte, which is intermediate between Perovskite and the species Pyrochlore, Micro- lite, Koppite of the following section. In general the part played by titanium in the many silicates in which it enters is more or less uncertain. It is probably in most cases, as shown in the preceding ages, to be taken as replacing the silicon; in others however, it seems to play the part of agaaic element; in schorlomite (p. 510) it may enter) in both relations.

Jan 1, 1922

By Thomas L. Watson

A part of the field-seasons of 1900, 1901 and 1902 mas devoted by the writer to a study of the manganese ore-deposits of Georgia. A report embodying the results of this study is rapidly nearing completion, and when finished it will be published as a bulletin of the Geological Survey of Georgia. I believe, however, the importance of these deposits warrants a separate and earlier publication than that made possible by the Survey, in which the more important results of the study are briefly set forth. It is principally for this reason that the present paper has been prepared. Previous Work.—Some of the more important deposits of manganese occurring in the Paleozoic area of Georgia were studied to some extent previous to 1890 by Dr. Penrose;t and again in the early nineties by former State Geologist, J. W. Spencer. In a recent paper published in the Transactions, on the " Geological Relations of the Iron-Ores in the Cartersville District, Georgia," Dr. Hayes briefly mentions the manganeseores of the same district. Distribution of the Manganese-Ores.—Georgia is divisible into three geologically-distinct areas which, named in order from southeast to northwest, are (a), the Coastal Plain; (b), the Crys-

Jan 1, 1904

By Allan Gibb

The ores of copper are usually associated with minerals containing arsenic, antimony and bismuth. Whatever the means adopted for extracting the copper, these metals are usually found, to a greater or less extent, in the product. There is, however, usually some elimination in the various metallurgical operations to which the ores are subjected, and some attempt is made here to determine the degree to which this elimination is effected.

Jan 1, 1903