Search Documents

By S. R. Rao

Interaction of potassium amyl xanthate with pyrrhotite has been studied thermochemically. Heats of adsorption of xanthate on unactivated mineral and the mineral activated with cupric ions have been compared with heats of reactions between potassium amyl xanthate and ferrous and cupric salts. It is shown that xanthate is consumed by stoichiometric exchange with anions present at the mineral surface. The floatability of the unactivated mineral is poor since xanthate is precipitated in bulk without creating a hydrophobic surface on the mineral. At the activated mineral surface, xanthate is adsorbed in certain isolated patches (active spots) and thereby creates a hydrophobic surface. The hydrophobicity of the mineral is greatly improved by lowering the pH to 4.5.

Jan 1, 1972

By R. L. Grayson, Y. J. Wang

This paper presents an application of goal programming (GP) to major mining machinery purchases based on historical operating data on mechanical downtime and production. The GP technique, an extension of integer programming, is used to maximize an objective function comprised of deviations away from management-preferred financial goals. Different capital budgeting techniques are used to evaluate capital proposals, and the results of these analyses are combined and weighted in a maximization of profits objective function. The GP method gives an optimal solution to a multiple goal problem. A sensitivity analysis is performed to determine the effect of a variable production improvement condition or a variable budget control con¬dition on proposal selection.

Jan 1, 1984

US 4,185,078-In the recovery of rhenium values from an aqueous sodium molybdate solution contained in the hydrometallurgical processing of roasted molybdenite, improved results are realized by using a described extractant consisting of a quaternary ammonium compound and benzene or other highly aromatic solvent which dissolves a quaternary ammonium-rhenium complex Essentially all rhenium is recovered from the solution and the extractant can be regenerated and recycled. This patent is a continuation-in-part of US Patent No. 4,049,771, dated Sept. 20, 1977. L R. Quatrini and M.B MacInnis, assigned to GTE Sylvania Inc. Jan 22, 1980. 6 pp (423-49). Flied. 7-19-78 (926,167).

Jan 1, 1982

By I. Iwasaki, K. Adam

During wet grinding the electrochemical interactions between grinding media and pyrrhotite not only accelerate media wear but also adversely affect the suede mineral's flotation response. A possible remedy of the adverse effects on floatability by applying electric potentials to grinding media was examined. Flotation tests, Auger electron spectroscopy, and X-ray photoelectron spectroscopy were used to study pyrrhotite surface properties. Although anodic polarization of the steels increased metal loss by corrosion, pyrrhotite flotation recovery was increased. In the case of cathodic polarization, flotation recovery improved somewhat in a narrow range of overpotentials. At higher cathodic overpotentials, however, mineral floatability was progressively lowered although the corrosive wear of grinding media might be reduced.

Jan 1, 1985

By K. E. Merklin, F. D. DeVaney

Students of the modern blast furnace seem unanimously agreed that they are observing a major revolution in practice. Rather than changing construction and operation of the furnaces, most of the great advances now under way deal with the raw materials feed. Prepared burdens have gained increasing significance during recent years. Sizing, concentration, and agglomeration have all become bywords to greater production and reduced operating costs. The remarkable results with test furnaces in which self-fluxing sinter makes up part or all of the ore charge foretell even greater improvements. Other investigators have reported many of these advances, and it is enough to predict here that more and more operators will turn to the use of self-fluxing sinter.

Jan 3, 1960

By J. R. Linney

A HISTORY of the ore-mining and iron-smelting industry of the Adirondacks comprises a century and a half of pioneering by rugged individualists, both men and women. By geographical location, the climate is most severe-long, cold winters with heavy snowfall, and short seasons of vegetation growth; this, together with its remote location from large centers of population, adds considerably to the difficulties of conducting mining operations in this area.

Jan 1, 1943

By Stephen Krickovic

THERE is today no proven continuous mining machine that can be used under all the varying conditions found in most bituminous coal mines. During the last five years, however, both the machines and methods of using them have been improved. Coal operators can now exercise a fair degree of selectivity, except those who must struggle with thick and hard partings and operate in seams less than 40 in. thick. It must be realized, then, that more than one type of continuous miner may be used advantageously in the same coal mine. Although this appears to violate the standardization generally sought after, the gain can more than offset added maintenance and, to a lesser degree, operating problems.

Jan 12, 1957

By Milnor Roberts

WAR struck the mineral industry of Washington with cross currents that produced a peculiar result. The State's production of coal, industrial minerals, and metals for 1941, valued at $28,507,282, was increased in 1942 under war pressure to approximately $35.000,000. Meanwhile a tremendous demand had arisen for men to construct airfields and many other large projects for the Army and Navy in Washington and Alaska, and Government plants for the mineral industry costing $140,000,000 or more, as well as a call for employees in the U. S. Navy Yard at Bremerton, the sixty shipyards, the four Boeing airplane factories with many auxiliary shops, and hundreds of other plants turning out war materials. In spite of an influx of nearly 300,000 people, causing an increase of 17.1 percent in the population since 1940, according to the Census Bureau, the State clearly is still engaged in an unusual amount of war production in proportion to its population. A large proportion of the workers have been drawn from the mineral industry to the war plants, whether through motives of patriotism, high wages, or, in the Boeing plants at least, the glamour of the operation

Jan 1, 1944

By A. H. Heim

A method and apparatus for measuring gas porosities of rocks are described. The apparatus can be assembled from commercially available components. In principle, measurements are made by volume substitution at constant pressure. The maximum error is not more than 0.3 porosity per cent. Typical results are given. INTRODUCTION Determining the porosity of rock samples is one of the most important and yet most varied types of measurement in core analysis. Among the many techniques devised are the so-called "gas porosity" methods. An old and well known example is the Washburn-Bunting method.' The U. S. Bureau of Mines2-' described and later improved the apparatus for a now widely used method generally known as the "Boyle's law" method. In the present form of the Washburn-Bunting method,' the volume of air in the pores of a rock sample at atmospheric pressure is extracted and then collected in a graduated burette at atmospheric pressure. The volume of air is read directly as the pore volume of the sample. The absolute error in reading the collected volume of gas is independent of the total volume; thus, the relative error is larger when the volume is small, as it is for rocks of low porosity. In addition, the sample after measurement contains mercury, which limits its use for other analyses. The Bureau of Mines (or Boyle's law) method measures directly the solids volume of a sample from which the pore volume and porosity are derived, using a separate measurement of the bulk volume. Gas at a few atmospheres pressure is introduced into a sample chamber of known volume containing the rock sample. The pressure is accurately measured. Following, the gas is expanded into a burette at 1 atm, and the gas volume is read directly. From the initial pressure p, and the final pressure p2 and volume v,, the initial gas volume v1 is calculated using Boyle's law; that is, p1v1 = p2v2. Volume v, minus the volume of the empty sample chamber is the solids volume of the sample. The accuracy of the method is limited, unless corrections are made, by deviations of the gas from the "ideal" gas-law behavior assumed in the simple form of Boyle's law. The purpose of the present paper is to describe a method for measuring the gas porosity of a rock which avoids many of these difficulties. Gas volumes are measured directly with the same accuracy as the bulk volumes. Pressures of at least an order of magnitude larger than those of previous methods are employed to insure rapid penetration of the gas into the sample. While special equipment may be built to apply the method, the porosimeter may be constructed as well from commercially available components. For simplicity, the apparatus described will be referred to as the "Constant-Pressure gas porosimeter". THE CONSTANT-PRESSURE METHOD Fig. 1 shows schematically the arrangement of components comprising the present Constant-Pressure porosimeter. Briefly, the method is one of volume substitution and may be considered a null measurement. Omitting (for the present) some of the operational details, the method of measurement consists of the following three steps. 1. After evacuation, the volume of the measuring system (a ballast chamber, a manifold, two gauges and their connections) up to the sample chamber is filled with gas to a high pressure (- 1,000 psi). A sample of the gas at this pressure is trapped in one side of a sensitive differential pressure gauge to serve as the reference pressure for subsequent steps. 2. The evacuated sample chamber containing the rock sample is opened to the measuring system. As the gas expands into the chamber, the resulting decrease in pressure unbalances the differential pressure gauge. 3. The pressure is restored by means of a mercury volumetric pump. The volume of mercury injected exactly equals the free or void volume of the sample chamber (volume of empty chamber minus the solids volume of the rock within). From the injected volume and the known empty chamber volume, the solids volume is obtained and the porosity calculated. The pressure and the volume occupied by the gas are the same before and after opening the sample chamber. Expansion and compression of the gas are incidental operations and do not enter into the calculation of porosity. By the pressure balancing or nulling, the free volume of the sample chamber is merely substituted by an equal and measured volume of mercury. Since the measurements are at constant pressure, there are no compressibility corrections necessary for the sample chamber.

By D. E. Spiller

Introduction Precious metals recovery from ore can generally be accomplished using gravity concentration, flotation, and/or hydrometallurgical (leaching) techniques. The objective of this paper is to show why gravity concentration can be an important part of recovery systems that employ leaching as the primary unit operation. A brief discussion of modem gravity concentration equipment is also presented. Discussion Gravity concentration of ores has generated increasing interest in recent years. Reasons for this interest include: • Gravity concentration is environmentally attractive. There is little or no use of reagents. Hence, it is relatively nonpolluting. • The cost of cyanide has continued to increase. Therefore, cost savings may be realized whenever leaching feed tonnage can be reduced by preconcentration. • Compared to flotation and leaching, gravity equipment costs are low per processed ton. Field installation costs for gravity circuits usually are less because many' units are supplied as self-contained modules. Also, the cost required to supply services, particularly power, to a gravity plant site are also less. In situations where preconcentration at coarse particle size is applicable, significant grinding equipment savings may be possible. • Gravity circuit operating costs are also relatively low compared to typical flotation and leaching circuits. Reagents, power, maintenance, and manpower savings in a well-engineered gravity plant may be realized. Again, if grinding is reduced, significant power and steel (media and liners) savings are possible. •In recent years, more efficient gravity concentrating devices have been developed. Benefits to Precious Metal Leaching Gravity beneficiation can complement precious metal leaching in two ways. First, the recovery of coarse liberated values before leaching may reduce leach time requirements and may reduce reagent consumption. Second, gravity preconcentration can reduce the size of a leach plant by decreasing the quantity of material to be leached. Coarse gold and silver have been shown to leach rather slowly. Kameda (1949) and Habashi (1967) have investigated the kinetics of cyanide leaching systems. They concur that in a heterogeneous reaction, the rate of gold and silver dissolution is directly proportional to the surface area. Thus, the instantaneous rate of dissolution for spherical 0.37 mm (400 mesh) gold is theoretically -25 times faster than for the same amount of gold at .841 mm (20 mesh), based on data from Fuerstenau, Chander, and Abouzeid (1979). Conversely, coarse liberated, +.841 mm (20 mesh), gold is more readily recovered by gravity concentration than is fine, -.037 mm (400 mesh) gold. Therefore, it is apparent that the two recovery systems complement one another. Figure 1 data demonstrates the potential synergism. A sample of - 3.327 mm (6 mesh) Nevada gold-bearing ore was cyanide leached using conventional bottle-roll test procedures. Gold extraction was determined as a function of leaching time. A second sample split from the same leach feed material was hand jigged to remove a coarse heavy mineral fraction, including virtually all of the +.210 mm (65 mesh) liberated free gold. This second sample, with the coarse gold and heavy minerals removed, was subjected to an identical cyanide leach procedure. Figure 1 presents the resulting comparative extraction data. Note that the percent gold extraction for the sample containing no +.210 mm (65 mesh) free gold includes the coarse gold recovered by gravity. The data show that the sample containing coarse gold required about 72 hours of leaching time to achieve 80% extraction. This compared to about 22 hours of leaching time for 80% gold recovery from the sample that contained only -.210 mm (65 mesh) free gold. Thus, there was a 69% reduction in leaching time. The improved extraction data is not wholly attributable to coarse gold removal, but rather it was the combination of gold removal and rejection of other heavy mineral cyanide consumers or leach retardants. Further investigation was not warranted at this time. Preconcentration is the second manner in which leaching systems can benefit from gravity concentration. The premise is that preconcentration can reduce the quantity of leach feed, which, in turn, may reduce leaching costs. Figure 2 presents preliminary data developed by CSMRI for US Minerals Exploration (USMX). Centennial Exploration Inc., in agreement with USMX, is proceeding with evaluations to determine the suitability of various processing schemes for recovery of gold values from the Montana Tunnels property. The data shows how the ore can be preconcentrated by gravity techniques to result in a reduced feed tonnage to secondary extraction techniques, presumably flotation or cyanide leaching. Testing has shown that Reichert cones, followed by treating the cone concentrate on spirals, can deliver about 88% gold recovery in about 13% weight, that is, 87% weight rejection. Consequently, fine grinding and reagent costs are attributable to only 13% of the plant feed rate. Cost data is not yet available, but the potential exists for significant cost savings.

Jan 1, 1985

By W. P. Blake

Forging under the hydraulic press, which was introduced by Haswell in the year 1861, at the machine shops of the Imperial State Railway Company of Austria, has since been greatly improved, so that at the present time there are very few parts of machines which cannot be produced in this way, and at no greater cost than iron castings. The process is now used at Vienna chiefly for such parts of locomotives as cross-heads, link-bars, axle-box frames, etc., especially where the form is intricate, and there are many angles and projections. These objects weigh from 50 to 150 lb. or more, and it is claimed for them that they are not only much cheaper than ordinary forgings, but are much more regular in form and stronger. The results which Mr. Haswell has attained, after years of patient experimenting, were well shown in the Austrian Department of the Vienna Exhibition by a collection of the pressed objects in iron and steel, just as they left the moulds, with some of them cut asunder longitudinally and the surfaces etched, so as to show the internal structure or direction of the grain. Through the courtesy of Mr. Haswell and his son I saw the hydraulic presses in full operation at the works, drawing down large Bessemer ingots, cutting them up into blocks of convenient size, and forming various park of locomotives. They have two large hydraulic presses in use; the largest, with a piston 24 inches diameter, gives 1200 tons pressure, and the second, with an 18-inch piston, gives 600 tons pressure. The pressure in the pumps is 600 atmospheres. The action is vertical; the piston descends upon the work, and for forging ingots is armed with a hammer-like head. An ingot of No. 7 soft Bessemer steel, which was forged in my presence, weighed 2030 lbs. One end being placed upon the anvil, the piston is brought slowly down and crowded into the mass as if it were putty or dough, forcing it each way, but chiefly in the direction of the length of the ingot, this being the narrowest section of the anvil and hammer. The piston is then raised and the ingot is moved forward for a second squeeze, and so on, until the first half of the ingot has been reduced in thickness, when it is turned on edge and the operation is repeated. The ingot is then turned end for end and forged until the whole length has been re-

By Robert B. McCormick

WORLD WAR II has developed a use for the nonmetal mineral quartz crystal that was unknown in World War I. During the interim period of peace, experimental work in the radio field with the piezoelectric properties of quartz crystal resulted in the almost universal adoption of quartz-crystal radio oscillator plates to control frequency in radio broadcasting, police, commercial and amateur communications equipment. Telephone resonators and filters made from quartz crystal also were developed, which vastly improved the frequency control of long distance telephone circuits. EXPANSION OF THE INDUSTRY The sudden war demands of the armed services for radio equipment using quartz crystal for frequency control led to an unprecedented expansion of the manufacturing industry. It is estimated that the 1940 peacetime volume amounted to approximately $1,500,000, while today a vast new quartz-crystal industry supplies more than $150,000,000 worth of quartz oscillator plates to the Army and Navy each year. This demand has caused an enormous expansion not only of American manufacturing facilities but also of Brazilian mining output, virtually our only source of raw quartz crystal. Actual figures of imports and consumption cannot be cited, for security reasons, but certain comparisons have been made, which indicate the transformation of quartz crystal from a minor to a major nonmetal. Lends has shown that the value of quartz-crystal exports from Brazil is now about equal to that of phosphate rock produced domestically in 1941 and actually exceeds the combined value of crude feldspar, gypsum and fluorspar production in the United States in the same year. This great expansion under wartime pressure was not accomplished without some anxious moments, but all the demands of industry have been met and the Government has been able also to accumulate a substantial stock pile of material against future contingencies. INSPECTION AND GRADING OF QUARTZ CRYSTAL The swift growth of the quartz-oscillator industry necessitated the simultaneous evolution of methods and criteria for inspecting and grading quartz crystal. It has been found that, generally speaking, it is economically feasible to cut only crystals that are at least 30 per cent by volume free from major defects such as optical and electrical twinning, cracks and fractures. Blue needles, bubbles, "chuva" and other minor imperfections can be tolerated in the usable portion unless present in great excess. The present marketing system in use in both Brazil and the United States, as far as quality is concerned, depends solely on the "usability" of a crystal, which is defined in the Brazilian-American agreement2

Jan 1, 1945

By W. P. Blake

FORGING under the hydraulic press, which was introduced by Haswell in the year 1861, at the machine shops of the Imperial State Railway Company of Austria, has since been greatly improved, so that at the present time there are very few parts of machines which cannot be produced in this way, and at no greater cost than iron castings. The process is now used at Vienna chiefly for such parts of locomotives as cross-heads, link-bars, axle-box frames, etc., especially where the form is intricate, and there are many angles and projections. These objects weigh from 50 to 150 lb. or more, and it is claimed for them that they are not only much cheaper than ordinary forgings, but are much more regular in form and stronger. The results which Mr. Haswell has attained, after years of patient experimenting, were well shown in the Austrian Department of the Vienna Exhibition by a collection of the pressed objects in iron and steel, just as they left the moulds, with some of them cut asunder longitudinally and the surfaces etched, so as to show the internal structure or direction of the grain. Through the courtesy of Mr. Haswell and his son I saw the hydraulic presses in full operation at the works, drawing down large Bessemer ingots, cutting them up into blocks of convenient size, and forming various parts of locomotives. They have two large hydraulic presses in use; the largest, with a piston 24 inches diameter, gives 1200 tons pressure, and the second, with an 18-inch piston, gives 600 tons pressure. The pressure in the pumps is 600 atmospheres. The action is vertical ; the piston descends upon the work, and for forging ingots is armed with a hammer-like head. An ingot of No. 7 soft Bessemer steel, which was forged in my presence, weighed 2030 lbs. One end being placed upon the anvil, the piston is brought slowly down and crowded into the mass as if it were putty or dough, forcing it each way, but chiefly in the direction of the length of the ingot, this being the narrowest section of the anvil and hammer. The piston is then raised and the ingot is moved forward for a second squeeze, and so on, until the first half of the ingot has been reduced in thickness, when it is turned on edge and the operation is repeated. The ingot is then turned end for end and forged until the whole length has been re-

Jan 1, 1874

By F. G. Coggin

" If you could only get that motion into a machine," said a gentleman, as he watched the process of making a " van " on a shovel, and saw the copper roll up to the highest point, "it would beat the world for slime-dressing." This idea has led to many an effort to get into a machine that peculiar motion, called the " vanning motion;" and so cams, eccentrics, eccentric gears, levers, bell-cranks, togglejoints, links, springs, etc., have been brought into requisition, while a contribution has been laid upon all the conceivable motions, rolling, tumbling, swinging, jerking, tossing, dropping, tripping, intermittent, regular and irregular, or a combination of some of them, to which have been added percussion, concussion, and more discussion —all in a vain attempt to combine in a single machine the consecutive motions of the shovel, in washing, flowing, and tossing the van. The Patent Office Reports, and the various mills of the country, show, as a result of this, a lot of gimeracks, most of which never went beyond a first trial, finding their way to the scrap-heap. Others still running might as well be there; while some have considerable merit for dressing other and richer sands than copper. It does look tempting to see that clean edge of copper climbing up the shovel-blade; but those who have seen in it such visions of large fortunes have not considered the time it takes to make a van, compared with the small quantity treated upon the shovel; and this points to the reason for the failure of all that class of machines called " vanning machines," when used for dressing copper slimes, namely, a lack of capacity. The writer has come to this conclusion through an experience with the Rittinger side percussion-table of the most improved make, sent from Germany to the Calumet and Hecla Mining Company, and with the Ellenbecker tables, used by the same company, both of which are good types of that class of machines. In both of these machines, the tables are suspendetl by rods which allow them to swing, and they can also be adjusted for the purpose of varying the inclination of the table. In the Rittinger machine, the motion of the table is at a right angle to the flow of the slime, being produced by a wiper-cam which throws the table against a spring, which throws it quickly back against a stop, the percussion throwing up the mineral. In the Ellenbecker table, the motion is

Jan 1, 1884

By E. M. Wise

IN a previous communications the improvement in strength, harden-ability and color, occasioned by replacing gold in a typical gold-silver-copper alloy by various amounts of platinum, or palladium, was discussed. In the present paper the results of further studies upon the constitution and the nature of the hardening transformation in these alloys are pre-sented. This research may be summarized as follows: 1. The liquidus and solidus have been determined for the alloys of the palladium and platinum series. Cooling curves were utilized for deter-mining the liquidus of the palladium alloys but this method proved unsuitable for the platinum alloys so that a, novel quenching method was utilized for the latter. Both the liquidus and solidus of the palladium alloys increase steadily with the palladium content. The liquidus of the platinum alloys increases rapidly with the platinum content, while the solidus temperature increases with the platinum content up to about 14 atomic per cent platinum, but suffers no further increase with additional increments of platinum up to 20 atomic per cent at least, owing to a peritectic reaction. 2. Palladium, and even more effectively platinum, reduces the rate of grain growth. Owing to this fact and to the increase in the solidus temperature, "overheating" does little or no damage to alloys containing reasonable quantities of these elements. This is confirmed both by tensile tests and metallographic examination. 3. The excess phase present in one of the high-platinum-content alloys has been isolated and chemically analyzed and was found to consist almost wholly of platinum, gold, and copper, evidently derived from the compound AuCu, by the partial replacement of gold by platinum.

Jan 1, 1933

By Frederick Laist

While remodeling No. 1 section of the concentrator at the Washoe Reduction Works of the Anaconda Copper Mining Co. during the summer of 1912, for the purpose of ascertaining what additional metal recoveries could be made by improvements in concentration practice which had been developed by the staff of the Boston & Montana Reduction Department, at Great Falls, it was deemed advisable to carry on some experiments on the treatment of the regular mill tailings by roasting and leaching, to see whether the losses of metal values might not be still further decreased. In the course of these experiments about 5,000 tons of tailings were roasted, and of the resulting calcine about 200 tons were leached. The results were so satisfactory that it was decided to continue the work on a larger scale, particularly as regards the leaching end of the process, and construction work on an 80-ton roasting and leaching plant was accordingly commenced during the latter part of February, 1913, and is being pushed as rapidly as possible. 80-Ton Leaching Plant. This plant will consist of one 20-ft. roasting furnace of the Mac-Dougall type, specially adapted to the work of roasting for leaching; two leaching tanks, 32 ft. in diameter by 12 ft. deep, together with the necessary solution tanks, air lifts, precipitating launders, etc. It has been decided to precipitate the copper from solution on scrap iron, so as not to hamper the roasting and leaching departments by any weakness that might develop in the precipitating department. It is, however, the intention to experiment with a number of different methods of precipitation; for example, by electrolysis and by hydrogen sulphide. The acid required for the operation of this plant will be purchased, ad the quantity required is not sufficient to justify the installation of an acid plant. An acid plant will, however, be established in con-

Jan 1, 1914

By W. R. Shimer

In his valuable report on Finishing Temperatures and Properties of Rails,l Dr. G. X. Burgess, Chief of the Division of Metallurgy, U. S. Bureau of Standards, has begun a line of investigation which should be continued by those interested in the subject, and who have proper facilities for carrying out the work. For the past year or more the Bethlehem Steel Co. has been conducting experiments to learn the effect of rail finishing temperatures on their physical properties and microstructure and the results are here given for the consideration of those interested in the rail situation. Considerable differences of opinion have been expressed by various authorities, in the past, as to the effect of large or small grain size and high or low finishing temperatures of steel rails on their physical properties and wearing qualities. Low finishing temperatures and, therefore, low shrinkage, have been advocated on the theory that the wearing qualities would be improved. Others have recommended high finishing temperatures. The generally accepted cause for rail failures, due to the development of transverse fissures, is excessive wheel pressure on hard rails. One of the causes advanced for hard rails has been that they contain too high percentages of carbon and manganese; another that the rails were finished at too low a temperature, i.e., at or near the critical point. In the experiments herein described the rails were rolled from reheated blooms. All the rail blooms were charged hot in a reheating furnace and brought up to about the original ingot-rolling temperature before rolling into rails. These rails gave better results in deflection, withstood a greater number of drops before breaking, and showed greater ductility than rails of identically the same composition and section which were rolled direct from the ingot. Rails rolled from reheated blooms, finished at somewhat higher temperatures than when rolled direct from the ingot, have a different microstructure, which the writer does not believe is due so much to the difference in finishing temperatures, as to the difference in

Jan 1, 1915

By A. L. Holley

THERE is a growing demand for pure and cheap material for fine open-hearth steel ; a material not only very free from phosphorus, but from carbon and silicon; so that it may he rapidly converted into steel. Iron and steel scrap are not trustworthy as to quality, and they are often dear. There are three methods of purifying cheap materials for the open hearth. 1. Mechanical puddling, as done at Creusot, which removes 90' per cent. of the phosphorus from the pig iron. 2. Krupp's washing process (the conduct and results of which I fully described in a former paper*), which eliminates 70 to 80 per cent. of the phosphorus and most of the sulphur and silicon from pig iron. Neither of these processes would sufficiently purify, for very fine steel, those very impure pigs which are cheapest in many parts of the United States: 3. The process of producing directly from the ore an iron which is practically pure chemically, although mechanically mixed with the impurities of the ore. This is the oldest of iron processes ; one form of it, the Catalan forge, employed to produce charcoal blooms, is still in use, but its great cost is rapidly throwing it out of competition. Among the modern attempts to produce iron direct from the one, on a large scale and at a cheap rate, several have been in various respects successful. Dr. Siemens's process of treating a ton and a half or more of ore and the coal to deoxidize it, in a rotating gas furnace, and bringing out, in some four hours, a ball of chemically pure iron so soft that the fluid and impure slag may be squeezed out of it, is the most attractive and the most highly developed of all the modern direct processes. I have watched it, from time to time, since 1874, and have noted a steady improvement. It may now be said to have passed the experimental stage, although, like older processes, it must be adapted by practice to special materials. The cause which has been more potent than all others, including the defects of the best direct processes, to bring these processes into disrepute, is the waste-ful treatment of the direct product. With one or two exceptions (when failure was due to other and obvious causes), the direct product has been made into wrought iron (weld iron). Even Dr. Siemens has, at Towcester, in England, and at Park, Bro. & Co.'s, in Pittsburg, set up his apparatus for this purpose. Is it likely that

Jan 1, 1880

By A. L. Holley

There is a growing demand for pure and cheap material for fine open-hearth steel; a material not only very free from phosphorus, but from carbon and silicon; so that it may he rapidly converted into steel. Iron and steel scrap are not trustworthy as to quality, and they are often dear. There are three methods of purifying cheap materials for the open hearth. 1. Mechanical puddling, as done at Creusot, which removes 90' per cent. of the phosphorus from the pig iron. 2. Krupp's washing process (the conduct and results of which 1 fully described in a former paper*), which eliminates 70 to 80 per cent. of the phosphorus and most of the sulphur and silicon from pig iron. Neither of these processes would sufficiently purify, for very fine steel, those very impure pigs which are cheapest in many parts of the United States. 3. The process of producing directly from the ore an iron which is practically pure chemically, although mechanically mixed with the impurities of the ore. This is the oldest of iron processes ; one form of it, the CataIan forge, employed to produce charcoal blooms, is still in use, but its great cost is rapidly throwing it out of competition. Among the modern attempts to produce iron direct from the one, on a large scale and at a cheap rate, several have been in various respects successful. Dr. Siemens's process of treating a ton and a half or more of ore and the coal to deoxidize it, in a rotating gas furnace, and bringing out, in some four hours, a ball of chemically pure iron so soft that the fluid and impure slag may be sqneezed out of it, is the most attractive and the most highly developed of all the modern direct processes. I hare watched it, from time to time, since 1874, and have noted a steady improvement. It may now be said to have passed the experimental stage, although, like older processes, it must be adapted by practice to special materials. The cause which has been more potent than all others, including the defects of the best direct processes, to bring these processes into disrepute, is the wasteful treatment of the direct product. With one or two exceptions (when failure mas due to other and obvious causes), the direct product has been made into wrought iron (weld iron). Even Dr. Siemens has, at Towcester, in England, and at Park, Bro. & Co.'s, in Pittsburg, set up his apparatus for this purpose. Is it likely that

Jan 1, 1880

Book Review MAN-TO-MAN: THE STORY OF INDUSTRIAL DEMOCRACY. By John Leitch, Phila¬delphia, Pa. The B. C. Forbes Publishing Co., New York, 1919, 2.19 pp., 7 1/2 X 5 in. $2.00. "Man to Man" is a short, well-written, well-printed, easy to read and very interesting hook. It is an account of a method introduced into more than twenty industrial plants to give the workers a share in managing their own troubles. It is not a panacea for labor troubles and strikes, but neither have existed where the new method has been tried. The scheme is, in a word, to organize the working force like the government, having a cabinet composed of the executives, a senate composed of foremen, and a house composed of men elected by fellow workers from all departments. This governing machinery takes up all complaints of workers, investigates, reports, and settles. The increased profits due to economy and increased production from this cooperation are divided 50-50 between the company and the men. Experience has shown that, since inattention, tardiness, irregularity, and inefficiency tend to reduce their profits, all men very quickly, after once convinced of the sincerity of the management in their scheme of cooperation, eliminate them because it is for their personal profit. Astonishing results have been attained, including higher wages, greater output, lower unit costs, great reduction in labor turnover, elimination of waste, an increased loyalty and a waiting list of employees even in periods of labor shortage. Profit sharing as such and stock ownership as a benefit to industrial relations are discussed briefly and illuminatingly, although they are not believed by the author to he the best way to bring about the human relation between those who work,for and those who work with money. The author is not against unions but does not believe the union is the best medium for improving industrial relationship. The look is nowhere dogmatic but is always forceful and convincing and, being well written, is very entertaining. It is doubtful if "Industrial Democracy" is the right expression for the solution of the problem but certainly anything that will place on the shoulders of labor some of the responsibility of industry and will increase production is tine much-to-be-desired desideratum. It is a. contribution to the solution of our biggest problem and should be read by everyone who employs men and who has been worried by the labor turnover. P. E. B.

Jan 7, 1919