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By P. D. S. St. Pierre

IN recent years the use of high sulphur fuels and charges in steelmaking has necessitated rapid methods of slag control in order to insure the production of high quality steel. Several systems of control have been discussed in the literature, and of these the method described by Philbrook, Jolly, and Henry' has received the most attention recently. In their process the hydrogen ion concentration of an aqueous slag suspension is determined under controlled, but arbitrary conditions. The basicity of the slag may then be derived from a previously established pH-V ratio curve. Thus, by measuring the pH, some indication of the V ratio is gained, from which significant properties of the slag may be deduced. Philbrook et al. made no claims as to the theoretical justification of their treatment, but simply offered it as a rapid means of slag control. Encouraging results caused others to study the method and publish their findings.2-5 Although there was fair agreement on the efficacy of the method, no common parameter was evolved against which pH readings could be plotted. The results of the various determinations were related to such V ratios as CaO/SiO2 and CaO/ SiO2 + P2O5 by some,'-3 while others" plotted against "excess lime." Rivet,' however, found a simple proportionality between the hydrogen ion concentration and the sulphur content of the molten steel beneath the slag. Since slag control in North American practice is largely directed toward the efficient removal of sulphur from steel, Rivet's approach to the problem had the advantage of connecting directly a property of the slag with the impurity being removed. In view of the diversity of parameters used it seemed probable that some fundamental point was being overlooked in seeking a relationship. Examination of the literature revealed that much emphasis had been laid on experimental detail but scant attention paid to the fundamental aspects of the hydrolysis of the aqueous slag suspension. Consequently the present investigation was undertaken with the object of rectifying this deficiency and deriving, if possible, a parameter of general application. Petrographic studies on several matured Canadian open-hearth steel slags have shown that their major constituents are dicalcium and tricalcium silicates set in a complex matrix of iron oxides and ferrites. These phases are shown in Figs. 1 and 2. Free lime is frequently encountered in slags, but is not an equilibrium phase since on continued heating it dissolves forming silicates or ferrites. Thus, it appeared that a study of the hydrolysis of the major phases in steel slags would be profitable. The experimental technique used in the present work was a modification of that described by the other workers.'- Electrical conductivity measurements were also made on the suspensions, since Smith et al." had claimed advantages for this method in their paper on slag control. Experimental Procedure The compounds studied in this investigation were prepared in the laboratory by heating purified oxides

Jan 1, 1954

Reginald S. Dean (Manganese Extraction by Carbamate Solutions and the Chemistry of New Manganese-Ammonia Complexes, P. 55) was born in Rolla, Mo. and attended the Missouri School of Mines. Mr. Dean has worked as metallurgist with Western Electric Co. from 1920 to 1929 and with U. S. Bureau of Mines from 1929 to 1946 as chief metallurgist and assistant director, and has been a metallurgical consultant in Washington, D. C. since 1946. An AIME member, Mr. Dean has presented at least 50 papers before the society. Mr. Dean is a member of American Society of Metals, American Chemical Society and Electrochemical Society. C. O. Dale (Illinois Operations of the Eagle Picher Mining and Smelting Co., co-author with W. J. Rundel, P. 72) was born in Twin Bridges, Mont. and attended Montana School of Mines and received his B.S. in mining engineering in 1944. Mr. Dale was with U. S. Navy Air Corps. as an electronics technician and worked as an engineer with C. O. Dale & Sons, Anaconda Copper Mining Co. and with Eagle Picher Mining & Smelting Co. At present he is Wisconsin manager of Eagle Picher Mining & Smelting Co. The application of machinery to mining is of special interest to Mr. Dale. A member of AIME, Mr. Dale is on the Room and Pillar or Stope and Pillar Committee of Mining Subdivision for 1951 to 1952. Mr. Dale is a member of Montana Society of Engineers and Lions Club. Golfing, fishing and wood working are his hobbies.

Jan 1, 1952

By Byron E. Eldred

Generally speaking, the practical study of combustion has been made mainly from the stand-point of the steam engineer. This narrow view-point has left open a large field for scientific research on the application of combustion in other arts, where the conditions of heat-utilization are widely different from those presented in the steam-generator. The great economic importance of the boiler and the ease of measuring its performance, together with the comparative uniformity of conditions in the steam-generator, is, probably, quite largely responsible for the practical neglect of the study of the use of fuels in other arts save only on the basis of their thermal value. yet these other arts show quite plainly that a thermal-value basis alone is not sufficient. For example, in burning lime, under ordinary conditions of firing, a cord of wood will do as much work as a ton of coal, though the latter affords more than twice the number of heat-units. Similar results are evidenced in burning brick, in the roasting of certain ores, in reheating billets, and in many other, arts where heat is to be applied over extended areas to fragmental masses of more or less refractory materials. In these arts much is to be gained by a

Jan 1, 1911

PRESIDENTS DAVID THOMAS 1871 R W RAYMOND 1872-1874 A L HOLLEY1875 ABRAM S HEWITT 1876 T STERRY HUNT 1877 ECKLEY B COXE 1878 - 1879 WILLIAM P SHINN 1880 WILLIAM METCALF 1881 RICHARD P ROTHWELL 1882 ROBERY W HUNT 1883 JAMES C, BAYLES 1884-1885 ROBERT H RICHARDS 1886 THOMAS EGLESTON 1887 WILLIAM B POTTER 1888 RICHARD PEARCE 1889 ADAM S HEWITT 1890 JOHN BIRKINBINE 1891-1892

Jan 1, 1923

By Eugene Guccione

One of the world's most respected scientists, Dr. Hans A. Bethe (see box) has concluded that if anything can solve the energy crisis, it will be coal and uranium. "It is an illusion to think that we can solve our problem by energy conservation alone. For the next few years, conservation must play a very important role, but at the same time, we must see and develop all our alternative energy sources," he said. In his series of five lectures on the energy crisis, given at the University of Utah while he was visiting professor there during February 1974, Dr. Bethe examined all the existing and newly proposed energy sources. He very quickly ruled out solar power, wind power, and tidal power. Solar power, he said, would be 3% to 4 times more expensive than nuclear energy and would only make sense in tropical areas; wind power, which could at best produce one-tenth as much energy as solar, is "for the birds;" and tidal power, which can be exploited in only a very few coastal locations, is "for the fish."

Jan 5, 1975

By C. R. King

Most of the acid volcanic glasses such as obsidian, perlite, pitchstone, pumice, and pumicite (volcanic ash) are susceptible to some expansion if suddenly subjected to a suitably high temperature in a properly designed furnace, and subsequently suddenly cooled. Expansion results from the action of chemically combined or dissolved water expanding as a vapor within the softened heated rock particles. This expansion forms countless minute bubbles within the pasty mass of the natural glass particles. If the particles are cooled before these bubbles can escape, the resulting products are cellular, more or less spherulitized glass froths or hollow glass spheres of many types. Chemically, they are essentially aluminum silicates containing about 70 to 75 pct silica, 10 to 16 pct alumina, and 2 to 7 pct sodium plus potassium oxides. They are relatively resistant to attack by acids or alkalies, are resistant to heat up to over 1000°F, and are completely inert to insect or fungus attack. These products are of great potential value in many branches of industry as insulation materials, aggregates, fillers, abrasives, and additives. By proper selection of the perlite rock type and control of processing conditions, expanded perlite of a bulk density varying from about 2 to 20 Ib per cu ft can be • made. The physical properties of the particles comprising a product of a given bulk density also may be varied within wide limits of porosity, water absorption, and crushing strength. In general, crushing strength of expanded perlite increases in direct relation to increase in bulk density, but insulating value varies in inverse ratio to bulk density. The selection of a particular grade of expanded perlite for a given use as an aggregate is therefore always a compromise between insulating value, lightness, and friability. If porosity and water absorption are factors affecting the use of the material, factors other than bulk density are important. Some types of perlite rock tend to decrepitate excessively during expansion, resulting in a highly porous or even hygroscopic product of high friability relative to the bulk density of material produced. In general, treatment of any good perlite rock below the temperature necessary for maximum expansion, or insufficient time in the hot zone of the furnace for effective heat penetration to the core of the rock particles will result in some decrepitation and high porosity in the expanded product. On the other hand, exposure of the material to the temperature required for optimum expansion for a period of time slightly longer than that necessary for proper heat absorption will result in a slightly heavier product of extremely low porosity, i. e., a glazed surface. It is beyond the scope of this paper to describe in detail the rock types and processing methods used to produce the many types of expanded perlite in present use, or that may be produced to fill the present and future needs of industry. A few phases of the economics involved in processing and selling products made from this abundant and cheap mineral raw material, plentifully distributed in large and relatively accessible deposits in most western states and in other areas within economic shipping distance of large centers of consumption, will be treated with particular reference to the Los Angeles area. Relation of Balk Density to Use and Cost of Production Perlite differs from most other lightweight aggregates and fillers in that the raw material (perlite rock) may be quarried much as rock arid sand is mined, and then shipped into consuming areas as crude rock in open gondola cars at correspondingly low freight rates and handling costs. At processing plants in or near large consuming areas the rock is converted into relatively fragile, very bulky products which in most cases are used within a short haul of the processing plant or enter into a manufactured product made at the site of the perlite processing plant.

Jan 1, 1950

The work of the Committee on Industrial Preparedness* is well summed up in the following letter written by Thomas A. Edison, Chair-man of the Naval Consulting Board, after President Wilson and signed the army appropriation and army reorganization bills: "The Committee on Industrial Preparedness of the Naval Consulting Board, of which committee Howard E. Coffin is chairman, after a five months' campaign in many ways unique in vigor and vision has played a very definite part in the measures for the national defense which have just become law. It is responsible for having laid the foundation for a true industrial preparedness in this nation. "Five months ago the committee, wholly non-partisan in make-up, acting with the civil, mechanical, mining and electrical engineers and the chemists of the country, members of five great scientific bodies, began its work in' every nook and cranny of the land. The purpose was to prepare American industry efficiently to support the armed forces of America in the event of war. "The public, the business men and the legislators at Washington knew little regarding the demands on industry in connection with modern war. No department at Washington was charged with the duty of coordinating the needs of the army and navy with transportation, industry, and kindred functions. The purchasing, quartermaster's and ordnance departments of the army and navy were unable to buy military supplies except by competitive offering in the open market. No one had considered the need, and no legislative machinery was in existence, for preventing the presence of skilled workers on the fighting front when they would in time of war be needed in the factories, mills and mines of the country. Neither at Washington or elsewhere was there even a list of the industrial resources of the nation in such shape as could be used for practical purposes in case war should come. "The three things, then, that the committee headed by Mr. Coffin set out to do and that now have been brought about were as follows: First, to mobilize concretely the business men of America and their output against a day of need. This meant chiefly to discover in fullest detail just what equipment our manufacturers possessed that might be swung over to supply the army and navy swiftly and bountifully from the hour the colors were raised. In a few weeks this initial task, which has been a truly colossal one, will be at an end. A complete report of the equipment of practically every concern of substantial size in the country is now in the hands of the - committee. Directly in charge of the great inventory has been W. S. Gifford, Supervising Director of the Committee. The second step was to procure legislation making possible the placing by the war and navy departments of annual orders for munitions in small quantities to American manufacturers now not producing such things, so that quietly, efficiently and thoroughly they could learn in time of peace how to supply the government in time of war. The new laws make all this possible. It should be said here that this practice will bring about a geographical diffusion of munition plants all over our country, instead of affording us only a few such concerns for the most part near the exposed seaboards, as at present. It is obvious that this system will also throttle all talk of a munitions trust.

Jan 10, 1916

By F. W. Smith

Within the Northern Pennine Orefield, England, intersections of fluorite veins are generally richest in ore, and their recognition enables investigation of the ore potential of the intersecting bodies. A method, based on routine analysis of fluorite for yttrium, has been used with success in mines of the district to predict the location of intersections in partially developed fluorite-bearing ore bodies. This short note is intended as a brief introduction; the details of United Kingdom applications are to be published at a later date. Geology The Northern Pennine Orefield is the second largest fluorspar-producing region in Britain. The associated minerals galena, sphalerite, chalcopyrite, barite, and witherite have all been extensively worked in the past but, with the exception of a single barytes mine, all of these operations are now abandoned. Galena alone is recovered as a byproduct of fluorspar beneficiation. At the present time two companies are producing about 38,000 tpy of fluorspar from high grade vein ore bodies, and a number of concerns are actively prospecting in old lead workings. The mineralization is localized in veins and replacement flats within favorable lithologies in an alternating limestone, sandstone, shale sequence. Since the thickness of individual beds is not great (generally less than 20 m), vein bodies tend to be ribbon-shaped, with length greatly exceeding width and height (Dunham). They thus present difficult exploration targets for conventional diamond drilling techniques. Ore grade varies greatly along the veins, which can change rapidly in character from mineral stained fault gouge to massive mineral bodies up to 10 m in width. It has been known for a very long time that the richer ore bodies tend to be associated with vein intersections in favorable beds. It is assumed that vein fissure intersections provided vertical channelways through which hot ore-bearing brines were able to ascend from deeper cavities in the sequence. Thus investigation of intersections at other horizons generally yields further ore bodies. Technique The relative concentration of yttrium in fluorite is a good indicator, in the North Pennines, of the direction of flow of mineralizing fluids. In all of the ore bodies so far studied in detail in this region, the concentration of yttrium increases markedly in the direction of vein intersections that are believed to have acted as feeder zones to the remainder of the bodies. The reason for this relationship is probably connected with the degradation of soluble rare earths-fluoride complexes by the changes in various physicochemical parameters of the hydrothermal fluids as they entered the ore body cavities from the feeder zones. The simultaneous release of free fluoride ions also contributed to the increased ore values in these intersection zones. Yttrium values in fluorite taken from a longitudinal traverse of the western ore body, Redburn mine, Rookhope, are plotted in [Fig. 1.] The position of a major vein branch and three cross veins are clearly indicated by yttrium maxima. The cross veins themselves contain up to 2.5 m of low grade fluorspar ore. The exact positions of B and C were unknown previous to the geochemical survey. Similar results have been obtained for several other veins and ore bodies in the area. Clean fluorspar was collected as bulk samples from within 300 mm of the vein wall and, since the vein infilling is simple, with mineral growth from the walls inward, analyses of the samples are considered comparable along the length of the ore body. A number of samples taken from the center of the vein show a

Jan 1, 1975

By W. R. Hamilton

The knowledge of the existence of petroleum in Southern California dates back to the days of the missions. The presence of asphaltum and semisolid bitumen was reported at Santa Barbara in 1792, but no serious attempt was made to develop oil until Professor Silliman's optimistic report in 1865 started California's first oil boom. Wells were drilled in many counties of the State, but the equipment was unsuitable and the drilling difficult and no production was obtained except in Ventura County. Even there the production was of little importance commercially, and not until the early '80s did it become sufficient to again attract attention. In 1888 the production for the State had reached a total of about 700,000 bbl. per year, practically all light oil produced in Ventura County, Pico Canyon, Los Angeles County and in the Puente Hills. The production of petroleum attained the dignity of an industry in 1895 when the Los Angeles City and Coalinga fields were discovered. The subsequent development has been remarkable, and in 20 years the production has increased from 1,000,000 to 100,000,000 bb1. per year. The refining industry has kept pace with the production of oil. The Pacific Coast Oil Co., the predecessor of the Standard Oil Co. of California, was the virtual pioneer refining company of the State, having built a refinery at Alameda about 1880. When purchased by the Standard, about 1902, it was dismantled and the refinery at Point Richmond was built. The Richmond refinery is now one of the largest in the world, having a capacity in excess of 60,000 bbl. per day. A small refinery was built by the Union Oil Co. at Santa Paula in the early days of the industry and later many asphalt refineries were in operation in Southern California. The Pacific Coast Oil Co. was then, as has been its successor, the Standard Oil Co. of California, the principal refiner and marketer of light products, the most valuable of which was kerosene. Before the opening of the twentieth century, gasoline of excellent quality was produced, though it was always a drug on the market and was produced for the simple reason that its presence rendered the flash and fire tests of the kerosene too low. The user of kerosene at the present

Jan 1, 1917

E. S. BARDWELL,* Great Falls, Mont. (written discussion ?).-There are several points in. connection with the manufacture of ferromanganese in the electric furnace which it seems to me. might prove of interest in this connection. Recent observation of a, number of electric furnaces varying considerably in size and transformer capacity, and all working under the same conditions, shows the small furnaces to be much more efficient in operation than the large furnaces. The furnaces examined were all of the same type. The crucibles consisted of tanks varying in size from 71-z by 15 ft. by 4 ft. deep, to 12 by 20 ft. by 9 ft. deep, with linings formed of carbon electrode butts. The smaller furnaces had transformer capacity rated at 1500 k.v.a.; the largest furnace had a transformer rated at 3000 k.v.a. All of the furnaces were operated on three-phase, 60-cycle current, the three electrodes being in a straight line. The voltages varied from 65 volts in the smaller to 100 volts in the larger furnaces. The charges consisted of manganese ore, coal, iron turnings, and limestone in proper proportions. The small furnaces, operating at low voltage, were making good recoveries. The slag loss was low and the volatilization loss almost nil. The larger furnaces, operating at higher voltages, showed increased loss of manganese in the slag and greatly increased volatilization loss when working on the same charges as the smaller furnaces, or on charges similarly calculated. The exact reasons for this state of affairs are difficult to state; a number of factors probably contribute to the results obtained in the large furnaces. First as to the effect of the higher voltage on manganese content of the slags. Increasing the voltage of the furnaces apparently tends to promote irregular working. The current takes the path of least resistance; this means superheating in certain areas in the crucible and insufficiently high temperatures in adjoining areas. The partially reduced manganese in the cooler areas passes into the slag and escapes further reduction.

Jan 11, 1918

By J. B. Hiskey, W. J. Schlitt, W. G. Pitt

Aqueous SO2 (sulfurous acid) is an interesting chemical compound. It functions as a reagent in various hydrometallurgical systems, but also represents an undesirable constituent in gyro- and hydrometallurgical effluent solutions. When present in such streams, SO2 can be oxidized to the more stable sulfate form to avoid exsolution of SO2 as a source of fugitive emissions and to simplify standard water treatment plant operation. This study provides information on the stoichiometry, kinetics, and mechanism of SO2 oxidation using oxygen and an iron salt catalyst with solutions containing 0.05-20 g/L (0.002-0.7 oz per gal) SO2. The effects of iron salt concentration, oxygen pressure, temperature, degree of agitation, and pH on SO2 oxidation are also described.

Jan 1, 1984

By L. D. Jaffe, H. C. Mann, E. L. Reed

It has been generally believed that fracture originates at a point and, if the stress is suficient, propagates across the material from this point. Evidence to the contrary is given in Fig 1. This micrograph shows an area close to the fracture of a steel containing The material had been quenched from 1675°F and tempered at 1150°F as a round about 10 in, in diam, and had a static tensile strength of 132,000 psi and a static yield strength of 105,000 psi. The steel was broken in 3000 cycles of reversed bending at a nominal max. fiber stress of 110,000 psi at a speed of 10,000 rpm. It was in the form of a standard R.R. Moore specimen with 45" V-notch, 0.015 in. radius and 0.220 in. diam at base of notch. The fractured edge in Fig 1 is part of the central portion of the specimen which broke during the final sudden fracture. Attention is directed to the short cracks which appear as dark lines within the specimen. Similar cracks were found in another specimen of the material, broken in 1,798,000 cycles at a nominal stress of 40,000 psi. The cracks were found in several areas close to the path of the final sudden fracture. This final fracture appeared microscopically to be wholly brittle and transcrystalline. Closer to the surface of the specimens, near the path of progressive fracture, which presumably advanced gradually during many cycles, there was microscopic evidence of some local deformation, but no microcracks. Neither were microcracks observed in areas distant from the main fracture path. The following explanation is offered: In the sudden fracture of the specimen, a crack propagates along a crystallo-graphic plane, with little or no plastic deformation of the adjacent material, until it reaches a grain boundary or a particle of carbide or inclusion which stops its advance. (The particle or boundary may be outside the plane of polish and not visible in the micrograph.) A stress concentration occurs about the end of the stopped crack. One or more new cracks are likely to start in the zone of this stress concentration. They may lie in the same grain as the first crack or in an adjacent grain. New cracks may occasionally start in a nearby but not adjacent grain whose orientation with respect to the stress leads to more ready fracture than does that of the grain between. Once started, these cracks propagate along crystallographic planes in their grains and the process repeats. This leads to discontinuous, branching chains of microcracks. As the process continues, microcracks probably tend to link up by fracture of intermediate material under the influence of increasing stress concentration. Occasionally, too, there may be a series of nearby grains of similar orientation so that there is a certain continuity of fracture across them. In either case the effective size of a crack is increased, resulting in greater stress concentration at its ends and a greater likelihood of further increase of size of the continuously-fractured region. When one continuous crack crosses the entire specimen, macroscopic fracture has occurred. The fractured edge of the specimen in Fig 1 represents a series of microcracks which became continuous across the entire specimen. The short, dark-appearing cracks in the figure did not become continuous over a large area. The row of microscopic stress concentrations at their ends may link up with those of the "main crack" outside the plane of polish. The above explanation does not imply that microcracks develop at the same rate in all portions of the specimen. They will develop most rapidly where the macroscopic tensile stress and macroscopic stress concentration are greatest. Viewed on a scale large compared to the grains, the fracture would appear to progress continuously across the specimen. Although Fig 1 shows a specimen broken in a fatigue test, it is believed that the microcracks discussed do not depend on the repetitive nature of the stressing used, since they are in the region where "sudden" fracture occurred, presumably in a single stress cycle. The whole process of microcrack propagation outlined above is thought to have occurred during this single cycle. It is believed that discontinuous crack propagation may be universal in brittle transgranular fracture of crystalline solids. Further experiments are under way.

Jan 1, 1950

Discussion of the paper of K. Huessener, (Trans., vol. 53, pp. 402 to 4333, and of the papers of Linn Bradley, H. D. EGbert and W. W. Strong, pp. 303, 319. R. J. WysoR, So. Bethlehem, Pa. (communication to the Secretary*). —At our plant (Bethlehem Steel Co.), we have had several Bradshaw burners under course of construction and erection for some time, but up to the present we have not had opportunity to put them in service. I regret that I can not take part in the discussion with some actual results from these burners. Mr. Huessener properly emphasizes the importance of obtaining the highest combustion temperature practicable in boiler practice, which demands a near approach to perfect combustion conditions. The ideal burner is the one which, while meeting the various mechanical requirements, fulfills the above condition under a wide range of gas pressure. The question as to the relative value of hot raw gas and cold washed gas for boiler use is a very interesting one. I think that in the past the importance of low temperature of washed gas sometimes has been overemphasized. Mr. Huessener has pointed out that so far as temperature is concerned, no advantage accrues in washing gas below 100" F. In many plants, there is a notable operating economy in using furnace cooling water, which is appreciably warmer than the supply water. However, in a given type of washer, other conditions being constant, the lower the exit gas temperature the lower will be the dust content; this is equivalent to saying that the more washing water is used, other conditions being constant, the lower will be the dust content of the exit gas. For each type of washer there is a certain desired average temperature difference between inlet water and exit gas, concomitant with known average dust and moisture contents, and with economical operation. With the present tendency toward smaller stove checkers, it is generally agreed that gas for stove use should be cleaned to a dust content of 0.20 grain or less. The method employed and extent of gas cleaning are clearly problems for individual furnace plants. As a general proposition, wet washing is decidedly more attractive for furnaces smelting soft, fine Lake ores than for those reducing chiefly hard, lumpy ores, such as the foreign and domestic magnetites. In the former case the average moisture content of the gas is probably 35 grains per cubic foot, the dust content is relatively high and the top temperature relatively low. In our plant, the ore mixtures consist almost exclusively of hard magnetites. The average dust content of the gas leaving the dust catcher will average only about 2 grains and the moisture about 12 grains per cubic foot, corresponding to saturation at about 83" F. The temperature is fully 100" F. higher

Jan 1, 1917

By D. J. Oswald, J. G. Ziegler

It is of common knowledge that loading within a grinding mill, whether ball, rod, pebble, or autogenous, is directly related to the lubrication back pressure developed between the mill journal and bearing shoe during mill operation. The merits of both forced-feed and gravitational-feed bearing lubrication methods are discussed with particular emphasis directed toward their applicability to continuous grinding mill inventory control. Data obtained from wet grinding mill applications in the cement and mining industries is presented to more clearly define the influence of such variables as feed consistency, slurry viscosity, mill retention, bearing oil temperature, grind fineness, and grinding media wear on the measured journal lubrication back pressure during automatic mill feed control. Finally, various grinding mill control schemes for maintaining constant mill loading and consequently optimizing mill operating efficiency are discussed and evaluated as to their advantages and/or disadvantages.

Jan 1, 1974

By Arthur F. Wendt

Within the last few years the production of iron, and of the metals generally, by a given furnace-plant, has been largely increased, in many instances trebled. Iron-furnaces exceeding one hundred tons' capacity per diem are now the rule in new constructions. Copper and lead-furnaces smelting from 60 to 100 tons of ore per day are common. With this greatly augmented product, the life of furnace-linings has been diminished, and recourse has been had to various cooling devices for prolonging the life of such liuings. The object of this paper is to call the attention of the profession to an arrangement recently patented by the writer. The common course of projecting water against the exterior of the brickwork of a furnace has been in a large measure abandoned by our most progressive managers. All have recognized the danger of this proceeding, especially when applied to the crucible of a furnace below the line of the tuyeres. Cast-iron water-jackets, with wroughtiron pipes for circulating the cooling-water, have replaced the cruder methods. In iron-smelting the use of such jackets has been confined to the crucible and the space around the tuyeres; and it has been the custom to support the jackets on the brickwork of the furnace. But the erosion of the brickwork below tuyere-jackets allows them to sag, and often displaces the alignment of the tuyeres and leads to other annoyances. The principle of construction adopted by the writer to remedy this and other evils, is to use a thin fire-brick lining (not over nine inches) from the tuyeres up to the bosh, to back this lining with wrought-iron or steel water-jackets, hung from the mantel-ring, and thus to carry the whole weight of the furnace and its filling upon the supporting pillars. The crucible proper is lined with three or four thicknesses of fire-brick on the sides, and not less than forty-eight inches in the bottom. It is supported on independent pillars, and is practically an independent structure. It could even be placed on wheels and made removable, were there any adequate advantage to be gained by such an arrangement.

Jan 1, 1885

By N. H. Murlenberg, T. M. Drown

It is often a tedious matter to get a solution of pig iron or steel, for the determination of phosphorus, which is absolutely free from silica. Where pig iron rich in silicon is dissolved in hydrochloric or nitric acid in the usual procedure, it is necessary, not only to evaporate the solution to complete dry ness, but to heat the dry residue for some beam in an air-bath to a temperature of about 120° C. The oxide of iron is thus rendered insoluble in nitric acid, and is only slowly dissolved by hydrochloric acid. In the method of determining silicon by nitric and sulphuric acid, described in the Transactions of the Institute, Vol. VII, page 346, arid Vol. VIII, page 508, we obtain in one or two hours a solution of the iron in the form of ferric sulphate entirely free from silica, and containing free sulphuric acid. It occurred to Us that this solution might be made available for the determination of the phosphorus by the molybdate method. The following experiments mere tried with unsatisfactory results. 1st. The iron was precipitated by ammonia, the precipitate filtered, washed, and dissolved in nitric acid. 2d. The iron was precipitated as basic acetate and dissolved in nitric acid. 3d. The solution was neutralized by ammonia, and nitric acid added in small excess. In all these cases the phosphorus obtained by precipitating by ammonium molybdate and magnesia-mixture was too low. The following method was then tried with success. The filtrate from the silica and graphite was evaporated to small bulk and heated in a porcelain dish on a sand-bath. until fumes of sulphuric acid ceased to escape. The dry residue was taken up with dilute nitric acid and the solution precipitated by ammonium molyldate. The phosphorus was weighed as magnesium pyrophosphate. The results were satisfactory. To save time, the original solution of the iron in nitric and sulphuric acids was evaporated to dryness and heated as before until

Jan 1, 1882

By N. H. Muhlenberg

IT is often a tedious matter to get a solution of pig iron or steel, for the determination of phosphorus, which is absolutely free from silica. Where pig iron rich in silicon is dissolved in hydrochloric or nitric acid in the usual procedure, it is necessary, not only to evaporate the solution to complete dryness, but to heat the dry residue for some hours in an air-bath to a temperature of about 120° C. The oxide of iron is thus rendered insoluble in nitric acid, and is only slowly dissolved by hydrochloric acid. In the method of determining silicon by nitric and sulphuric acid, described in the Transactions of the Institute, Vol. VII, page 346, and Vol. VIII, page 508, we obtain in one or two hours a solution of the iron in the form of ferric sulphate entirely free from silica, and containing free sulphuric acid. It occurred to us that this solution might be made available for the determination of the phosphorus by the molybdate method. The following experiments were tried with unsatisfactory results. 1st. The iron was precipitated by ammonia, the precipitate filtered, washed, and dissolved in nitric acid. 2d. The iron was precipitated as basic acetate and dissolved in nitric acid. 3d. The solution was neutralized by ammonia, and nitric acid added in small excess. In all these cases the phosphorus obtained by precipitating by ammonium molybdate and magnesia-mixture was too low. The following method was then tried with success. The filtrate from the silica and graphite was evaporated to small bulk and heated in a porcelain dish on a sand-bath, until fumes of sulphuric acid ceased to escape. The dry residue was taken up with dilute nitric acid and the solution precipitated by ammonium molyhdate. The phosphorus was weighed as magnesium pyrophosphate. The results were satisfactory. To save time, the original solution of the iron in nitric and sulphuric acids was evaporated to dryness and heated as before until

Jan 1, 1882

By G. G. Gunther, C. L. Boeke

(Any discussion resulting from presentation at the Los Angeles Extractive Metallurgy Division Meeting will appear in the November 1953 issue.) I. M. Symonds (Cia Minera de Penoles, Monterrey, N. L., Mexico)—This is a most interesting paper describing zinc deleading operations. Mr. Gunther was kind enough to show me his operation last fall. Outside of the excellent results, I was most impressed by the ease of control. I had expected a difficult operation requiring careful control and supervision, but found one requiring little attention. The only disappointing fact of the separation is the poor copper recovery in the concentrate of the deleading float. The final zinc concentrate still has about 3 pct chalcopyrite (assuming the copper is chalcopy-rite) which adversely affects the zinc grade. If the copper mineral is free, the poor recovery is probably due to the high cyanide concentration. Fortunately, about 75 pct of the copper is recovered before the pulp goes to the zinc circuit. Mr. Gunther's remarks about proper cyanide to zinc sulphate ratios cannot be overemphasized. Although our experience has been mostly confined to the conventional Pb-Zn separation, we have found these ratios most important, and more important in the mill than in the laboratory. The laboratory appears to give optimum results over a wider range of reagent control than the mill, especially in regard to the effect of cyanide. In the mill in handling relatively high grade ores, we usually find that ratios of cyanide to zinc sulphate of 1 to 10 or 20 or higher work best. Where there is a substantial amount of chalcopyrite present, it has been noted that cyanide in the range of 0.02 to 0.10 lb per ton of ore is often beneficial in zinc rejection and possibly in copper recovery in the lead concentrate, while larger amounts, say 0.20 to 0.25 lb per ton, will float more zinc and cause a serious rejection of chalcopyrite. On an ore with 15 to 20 pct Zn content, we have had to use 0.8 to 1.2 lb of zinc sulphate per ton of ore with the above cyanide to obtain optimum results. Sometime ago we made a laboratory study following Parral and Santa Barbara practice on an ore which never had a very satisfactory rejection of zinc in the lead concentrate. The results were not encouraging and a mill test was not run. Since then the study has been reopened using fresh zinc concentrate from the mill in the laboratory instead of one made in the laboratory. A reasonably clean lead float from the zinc concentrate was obtained. It has been checked several times and each time the zinc concentrate made in the mill responds and the one made in the laboratory does not. Although undoubtedly some reasonable explanations can be given, it is presented here only

Jan 1, 1953

By C. A. Hartinagel

During 1941, the total production of crude oil in New York state was 5,185,000 bbl. This represents a small increase over the average for the past five years. From 1921, when the annual production of the state amounted to only 988,000 bbl., there was a regular annual increase in production (excepting one or two years) until the 5,000,000-bbl. mark was reached in 1937, After more than 20 years of oil recovery by flooding methods, it was generally believed, until a few months ago, that the rate of production was nearly at its peak and within a few years the fields would experience a gradual decline as the thicker sands became exhausted and the thinner ones could be worked only at increasing costs. As a result of the present emergency, however, unusual efforts are being made, in spite of higher costs of operation, to increase the output of Pennsylvania grade oil, to which the New York product belongs. Since most of any increased production would be obtained by flooding, and since floods travel slowly, no large increase in production can be expected for some months to come. During the first year, 10 or 15 per cent increase could be obtained, but maximum production, an increase of perhaps 40 per cent, could not be expected until some time during the second or third year. In the Allegany fields, which account for two thirds of the state's oil production, 1246 wells, including water-intake wells, were drilled during the year; 390 more than in the preceding year and 590 more than in 1939. It is evident that much of the best oil territory has already been developed. As producers move toward edge properties and thinner sands, returns will be smaller, whereas costs remain the same or, under war conditions, become higher. It is estimated that at least 60 million barrels of oil is in sight and will be produced from the thicker sands by present recovery methods. In the thinner sands and edge properties, some 35 million additional barrels can be produced at a profit only if prices become higher. In view of the fact that there is little hope of finding new oil pools in New York, one of the future problems of the oil producer will be to obtain adequate returns for increased production costs. The year started with a posted price of $2.15 per barrel of crude. There were five successive price increases until the high of the year was reached at $2.98 on Aug. 14. Eight days later the Office of Price Administration directed that the price be reduced to the June level of $2.75 a barrel, which remained in effect to the end of the year. With rising costs of operation, it is feared that many of the smaller properties cannot continue production unless the Federal price cut is revoked. During the year, Allegany Refiners Inc., a local enterprise founded in 1933, with plant at Bolivar, western Allegany County, increased its refining capacity from 1000 to 1500 bbl. daily. At the same time equipment was added to make the plant a complete lubricating-oil refinery, including facilities for the refining of wax into the finished product. Previous to the enlargement, it was necessary to sell the wax

Jan 1, 1942

By C. A. Hartinagel

During 1941, the total production of crude oil in New York state was 5,185,000 bbl. This represents a small increase over the average for the past five years. From 1921, when the annual production of the state amounted to only 988,000 bbl., there was a regular annual increase in production (excepting one or two years) until the 5,000,000-bbl. mark was reached in 1937, After more than 20 years of oil recovery by flooding methods, it was generally believed, until a few months ago, that the rate of production was nearly at its peak and within a few years the fields would experience a gradual decline as the thicker sands became exhausted and the thinner ones could be worked only at increasing costs. As a result of the present emergency, however, unusual efforts are being made, in spite of higher costs of operation, to increase the output of Pennsylvania grade oil, to which the New York product belongs. Since most of any increased production would be obtained by flooding, and since floods travel slowly, no large increase in production can be expected for some months to come. During the first year, 10 or 15 per cent increase could be obtained, but maximum production, an increase of perhaps 40 per cent, could not be expected until some time during the second or third year. In the Allegany fields, which account for two thirds of the state's oil production, 1246 wells, including water-intake wells, were drilled during the year; 390 more than in the preceding year and 590 more than in 1939. It is evident that much of the best oil territory has already been developed. As producers move toward edge properties and thinner sands, returns will be smaller, whereas costs remain the same or, under war conditions, become higher. It is estimated that at least 60 million barrels of oil is in sight and will be produced from the thicker sands by present recovery methods. In the thinner sands and edge properties, some 35 million additional barrels can be produced at a profit only if prices become higher. In view of the fact that there is little hope of finding new oil pools in New York, one of the future problems of the oil producer will be to obtain adequate returns for increased production costs. The year started with a posted price of $2.15 per barrel of crude. There were five successive price increases until the high of the year was reached at $2.98 on Aug. 14. Eight days later the Office of Price Administration directed that the price be reduced to the June level of $2.75 a barrel, which remained in effect to the end of the year. With rising costs of operation, it is feared that many of the smaller properties cannot continue production unless the Federal price cut is revoked. During the year, Allegany Refiners Inc., a local enterprise founded in 1933, with plant at Bolivar, western Allegany County, increased its refining capacity from 1000 to 1500 bbl. daily. At the same time equipment was added to make the plant a complete lubricating-oil refinery, including facilities for the refining of wax into the finished product. Previous to the enlargement, it was necessary to sell the wax

Jan 1, 1942