Search Documents

By William N. Poundstone

What attracts young engineering graduates into the coal industry? What do these young men expect of a career in coal mining? These questions are often asked and debated by mining men throughout the country. In order to present a comprehensive answer to them, an opinion survey was conducted at West Virginia University's School of Mines among the junior and senior classes and part of the sophomore class. The tabulation of the answers showed that the present-day mining engineering student is an older, more mature individual as compared with former years and as compared with other present-day college students. The average age of the country's record-breaking 150,000 college graduates is 24 years. Among this year's mining graduates at West Virginia University, 78% are of this age or older. Over half (54%) of those polled in the survey are married. This is com- pared to 30% as a national figure. Of those married, 38% have one child and over 6% have two children. The entire senior group covered by this survey has averaged almost three years in the armed forces. An article entitled "The Class of '49" in the June issue of Fortune magazine states that this year's class is the oldest, most mature class in history. Our survey indicates that the mining engineering students at West Virginia University are well above the average in this respect.

Jan 1, 1949

By E. A. von Hahn, T. R. lngraham

The rates of cementation of pd11 on electropolislzed copper cylinders were studied in aqueous perchloric acid solutions at pdII concentrations from 0.02 to 0.1 mM. The cylinders were rotated at various high speeds to reduce the diffusion layer to a minimum thickness. In 0.1 M HClO4 solutions, the cemented palladium is dense, adherent, and shiny. The rate data indicate that there are two stages in the deposition. In the initial stage, the rate of cementation is first order with respect to the pd11 concentration. The second stage is much slower. The first stage is consistent with rate control by the diffusion of pd11 ions to the copper surface, and/or chemical reaction at the surface, and the second stage is consistent with rate control by the diffusion of copper ions from the cop-per surface through the deposit of cemented palladium, out to the main body of solution. In 0.001 M HClO4 solution, only the first stage is evident and the rate is more rapid than at higher acidities. This rate enhancement is attributed to PdOH+ ions that predominate at low acidity and aye more reactive than unhydrolyzed pdII. The deposit is porous and loose. All of the cemented deposits are Pd-Cu alloys rather than pure palladium. Activation energies are 9.5 kcal per mole in 0.1 M HClO4 and 7.4 kcal per mole in 0.001 M HClO4. CEMENTATION or displacement reactions occur between aqueous solutions of metal salts and immersed metals according to the general equation: where M1 is electrochemically the more noble metal. Although these reactions find considerable application in metals recovery processes (e.g., the cementation of copper192 or gold3), in electrorefining processes (e.g., solution purification before electrolysis4,5), and in plating and metal finishing processes,6 few studies have been made of the kinetics of such reactions.7-9 The rates of cementation reactions will depend on one or more of the following factors: a) chemical reactions at the metal-solution interface; b) ionic transport to or away from the interface;'-' and c) the character and adherence of the cemented deposit on the substrate metal,6a,10 because the deposit will inhibit the rate of transport of dissolving ions (M2m+) into the solution. In this investigation, the kinetics of the early stages of cementation were studied to obtain an understanding of the reaction mechanism under conditions in which the deposit was sufficiently thin that its inhibiting effect could be disregarded. To achieve this, very dilute solutions in Mn+ were used. Cementation rates are often fast in the initial stages and transport-contr01led.9 To find conditions under which transport control would shift to chemical control, very high stirring velocities were used to minimize the diffusion-layer thickness. Of the many possible cementation reaction systems, the palladous perchlorate-copper system was chosen for this investigation because it was believed to involve simple ion-for-ion exchange. In addition, there are no interfering side reactions, such as the reduction of hydrogen ions, and anion effects are usually absent in perchlorate solutions. EXPERIMENTAL Materials. Reagent-grade chemicals and redistilled water were used in all experiments. Palladous perchlorate stock solutions (0.02 M) were prepared by dissolving 99.5 pct Pd sponge (Johnson Matthey and Mallory Ltd.) in concentrated nitric acid, adding concentrated perchloric acid, evaporating twice slowly (to prevent PdO precipitation) to a small volume, and diluting in a volumetric flask. To prevent gradual hydrolysis of PdII, the stock solutions were made 0.4 M in HC104. Tests for pdIV (Ref. 11) and C1- were negative. Copper strips were cut accurately from 0.025-in. electrolytic tough pitch sheet, Sample 1 (Mines Branch stock or Canadian Copper Refineries Ltd., Montreal), or from oxygen-free, high-conductivity sheet, Sample 2 (American Metal Climax O.F.H.C. brand, sold by Utility Brass and Copper Corp., Brooklyn). The strips were annealed for 1 hr at 335°C in a stream of purified nitrogen (Union Carbide, Linde Division) which had

Jan 1, 1967

By D. S. Tomalin, D. F. Stein

The effect of reducing oxygen to low concentrations on the fracture of high-purity iron single crystals has been examined at 78° and 20°K. It is found that iron single crystals grown by the strain-anneal method usually contain a few occluded grain boundaries which may become embittled in the presence of oxygen, thereby nucleating cleavage fractures. High purity with respect to interstitial elements was found to inhibit twinning and evidence is presented for an orientation dependence of the resolved yield stress. Deformation occurred by slip rather than twinning at both temperatures of testing with elongations of as much as 9 pct at 20°K. THE fracture properties of iron single crystals have been observedl-3 to be a function of temperature, orientation, and purity. Allen, Hopkins, and McLennan1 demonstrated that at 78°K iron single crystals became increasingly brittle as the tensile axis approached the (001) pole of the stereographic unit triangle. Iron crystals with the tension axis near a (001) pole were completely brittle and orientations near the (011)-(111) boundary were very ductile, achieving a 100 pct reduction in area prior to fracture. Later work of Biggs and pratt2 and of Edmondson3 demonstrated that by reducing the carbon content of the single crystals the transition between brittle and ductile failure at 78°K could be shifted to orientations nearer the (001) pole. Ed-mondson went further and pointed out that any mechanism which tended to increase the yield strength of the iron (i.e., carbon addition, pre-strain) also increased the tendency for brittle behavior at 78°K. Thus by a reduction of carbon content Biggs and Pratt were able to obtain ductile behavior to within 20 deg of the (001) pole, and Ed-mondson was able to obtain ductile behavior to within 26 deg of the (001) pole. Edmondson's material had a total interstitial content (carbon, oxygen, and nitrogen) of approximately 60 ppm and, although Biggs and Pratt reported no analysis, indications were that their iron contained comparable impurities. Stein, Low, and seybolt4 purified iron single crystals to a total carbon, oxygen, and nitrogen content of approximately 20 ppm. They observed a lowering of the yield stress with this increased purity, and thus one might have expected an observation of increased ductility. Although they tested specimens of orientations which the previous workers had indicated should be ductile, the crystals failed at a 78°K in a brittle manner with little elongation. Stein noted,' however, that about 90 pet of the failures could be traced in origin to occluded grains. Allen et al.1 and Edmondson3 do not report examination of their cleavage surfaces, but Biggs and pratt2 reported that microscopic examination of the cleavage surfaces of many of their specimens revealed the presence of small occluded grains. Honda and cohen6 and Keh7 have also observed the initiation of fracture at occluded grains in iron single crystals. Therefore, the additional complication of occluded grains must be considered in studying the properties of iron single crystals and the origin of fractures determined if the ductility exhibited by the crystals is to be considered meaningful. Various investigators8-12 have studied the effects of impurities on grain boundaries in high-purity polycrystalline iron. Rees and Hopkins10 showed that the addition of oxygen to low-carbon (0.002 pet) iron weakened the grain boundaries, causing a shift from transcrystalline to intercrystalline fracture and a progressive decrease on the brittle-fracture stress with increasing oxygen content. In addition, it has been shown by Low and Feustel11 that the addition of carbon to polycrystalline iron containing oxygen eliminated grain boundary brittleness. Thus, oxygen can embrittle grain boundaries in high-purity polycrystalline iron, but the addition of an appropriate amount of carbon can eliminate the oxygen-induced brittleness. The oxygen content (19 ppm) of the iron "single crystals" employed by Stein el al. was large enough to suspect impurity effects at the occluded grain boundaries. Allen et al.1 Biggs and pratt,2 and Edmondson3 may have masked any occluded grain problem in their specimens considering the relatively high carbon levels they employed. stein13 demonstrated that the addition of as little as 0.9 ppm C to previously purified (less than 5 x 10-3 ppm C) "single crystals" would increase the elongation from a few percent to more than 20 pet at 78°K and the fracture was not associated with grade boundary initiation.

Jan 1, 1965

By Paul A. Beck, M. N. Parthasarathi

The vecrystallization texture. formed by selective growth of random nuclei in an 80 pct volled 99.997 pct A1 crystal of initial orientation mear (123) (41.21 was found to consist of components related to the single-component rolling texture by 40 deg. rota-tiows around [111]axes. The relative-volume fractiovz of the various recrystallization-texture componezts may be accouzted for 012 the basis of the Lou) mobility of twist boundaries, if it is assumed that the mobility of the tilt boundaries also varies with their orientation. Similar results with a, aluminum-alloy cystal of the (110) [112] orientation, containing iron, silicon, and zinc, show that these solute contents do not impair the effectivezess of the oriented growth mechanism of re cry s-tallization- texture formation. In a previous investigation1,2 it was found that a sharp recrystallization texture is formed as a result of the oriented growth of random artificial nuclei in an aluminum crystal rolled to 80 pct RA, on the (110) plane in the [ 112] direction. Four recrystallization-texture components were found to occur, with orientations corresponding to 40-deg rotations around [111 1 axes of the deformation texture. Reorientations of this type were already found in earlier work,3,4 where the presence of random nuclei could be reasonably assumed, but was not rigorously documented. The same orientation relationship was found also by Lucke and Liebmann, who actually measured the orientation dependence of boundary-migration rates in the recrystallization of A1 crystals slightly deformed in tension.5,6 The occurrence in the recrystallization texture of only four of the eight crystallographically equivalent orientations of the type referred to above remained unexplained,1,2 although it was clearly not a result of the absence of suitable nuclei. Recently Burgers7 suggested that this effect may be due to the aniso-tropy of boundary mobility observed2'6; it was found that the recrystallized grains of the 40-deg [111]-rotated type grow much faster in directions perpendicular to the [ 111] they have in common with the matrix than parallel to this direction, i.e., the tilt boundaries have much higher mobility than the twist boundaries. The four orientations corresponding to

Jan 1, 1962

By Robert S. Baker

It has been demonstrated in the laboratory by A. J. Phillips1 that a transformation or conversion from beta directly to alpha may take place in a brass of 61 to 62.5 per cent copper content. The completion of the transformiation is dependent on a rapid rate of cooling from the all-beta field through the alpha + beta range to the alpha field. Phillips states that in a slowly cooled alloy containing 62 per cent copper and 38 per cent zinc the copper content of the beta is progressively decreased from 62 to 56 per cent by precipitation of alpha. Rapid cooling tends to prevent the separation of alpha with a copper content of more than 62 per cent by reducing to a minimum the time required for passing through the alpha + beta range. Upon crossing beyond the (alpha + beta) (alpha) boundary to the all-alpha region below, the material is transformed from beta to alpha. It, is essential that there be no change in composition. Phillips obtained his results by quenching a 62:38 copper-zinc alloy from 850" C. in iced brine at -8" C. No reference to the occurrence of this transformation in a manufacturing process has been found in the literature. An investigation of the microstructures of a number of hot forgings made from leaded brass rods yielded one forging in which this striking conversion from beta to alpha had occurred. The purpose of this paper is to describe the transformation and certain conditions under which it may occur during the hot pressing of brass. The conversion was noted in a shape forged from a leaded brass rod, the composition of which was: Cu, 60.26 per cent; Zn, 37.86; Pb, 1.88. In this study the lead content was disregarded and the alloy was considered to be equivalent to an alloy of 61.40 per cent copper and 35.60 per cent zinc (9812 parts = 100 parts). The possibility that the lead might obstruct or accelerate the precipitation of alpha was not studied. The lead appears as black globules in the photomicrographs and has a negligible solubility in the alloy.

Jan 1, 1932

. F. W. SPERR, JR.,* Pittsburgh, Pa.--Mr. Malcolmson states that the Carbocoal process produces ammonium sulfate in excess of that normally recovered in the ordinary byproduct coke process. Table 3 indicates that 20,000 to 25,000 lb. of sulfate of ammonia are obtained in carbonizing 1000 tons of Clinchfield coal. This is a high-grade coal and yields from 26 to 28 lb. of ammonium sulfate per ton in a modern byproduct coke oven. On the next page, 21 lb. is stated as the yield of ammonium sulfate per short ton of raw coal; this is less than the average production from any well operated byproduct coke-oven plant treating coal of the character usually coked, in Pennsylvania and Ohio. The statement as to the comparative yields of light oil is somewhat misleading in view of the results obtained during the past year or two by the more modern byproduct coke plants. The plants put in operation by the H. Koppers Co., during the past two years, are producing about 3.5 gal. of light oil per short ton of coal, and several of these plants are producing more than 4 gal. per ton. The yield of pure toluene runs from 0.45 gal. to 0.55 gal. per ton. .The quality of the light oil .obtained from the Carbocoal process is of much greater importance than would be inferred by one not closely familiar with the subject. The presence of paraffins in the benzol and toluol fractions seriously detracts from their commercial value; the benzol and toluol fractions derived fro in the Carbocoal process contain about 50 per cent, of paraffins. It should be thoroughly understood what these paraffins are. They are simply hydrocarbons that go to make up ordinary petroleum, and if a successful method for the removal of paraffins from benzol and toluol has been developed, this can at once be applied to several well known processes by which benzol and toluol can be made directly from petroleum, which have as yet been total failures on account of the contamination of these products by paraffins.

Jan 11, 1918

By C. M. Young

THE safety lamp is the most common and convenient apparatus for detecting inflammable gases in mines, the presence of gas being shown by a blue flame, called the cap, if the wick has been lowered to suppress the luminous flame. The height of the cap increases with the proportion of gas and with the temperature of the lamp flame. Lamps of the Wolf type, the fuel of which is benzine, have a hotter flame than lamps in which vegetable oils are used, such as the Davy, and the Clanny, and are more sensitive than the latter and their many modifications. The Piehler alcohol lamp gives a still higher cap while the Clowes hydrogen lamp is most sensitive of all. While the effect of the temperature of the source of ignition is well known, the writer knows of no previous attempt to correlate the change of this temperature with change of the height of the cap produced. In order to determine the height of the cap at various temperatures, it was necessary to have a source of ignition the temperature of which could he accurately controlled over a considerable range. This condition was met by a coil of wire of high fusing point heated by an electric current controlled by a variable resistance. The use of a coil offered the further advantage of freedom from complications due to the flame of a burning fuel. Such a flame, being itself of variable height, would to some extent raise or lower the elevation of the base of the cap and therefore add to the difficulty of determining the height of the cap. Besides this, the presence of a small cap from the lamp fuel, commonly known as the "fuel cap, " would interfere with the observation of small gas caps. After some experiment, a coil was made of platinum wire, No. 26, diameter 0.016 in. The coil was 17/64 in. (6.746 mm.) in outside diameter and had eight full turns in a length of ½ in. (12.69 mm.). This was connected to an electric circuit through an adjustable resistance, as shown in

Jan 8, 1919

By C. Richard Tinsley

INTRODUCTION Documentary complications arise from the risk apportionment in project financing which generally means that once the project is up and running and has satisfied the lender's completion test, the loan agreement specifically limits the lender's recourse to the project and its assets. It is the purpose of this paper to describe the special considerations which apply to industrial minerals projects and explore the reasons why so few project financings are negotiated in this industry. SIZE Small projects do not warrant the relatively high costs of negotiating and documenting project financing. The extent of the documentation is directly proportionate to either (a) the degree of risk apportionment, or (b) the amount of control given to lawyers to negotiate the documents. Although one would like to believe that project-finance documentation could be off-the-shelf, it is almost always necessary to tailor the documents to the mine development itself and the individual desires of the borrower. Accordingly, the documentation costs and initial expenses are seldom less than $40,000, and for complex projects can reach $400,000. In addition, banks often charge an up-front fee to partly compensate them for their staff time and partly to increase their yield on what is deemed to be a "riskier" loan asset. Another factor is the generally lower debt:equity ratio when bankers are uncertain of the accuracy of the cash flow projections. The ratio of the amount of cash flow left over after debt service to debt service itself is a key tool for project finance (debt service coverage). Bankers will require a higher coverage ratio for industrial minerals projects because of the relatively higher uncertainties in the following categories: Prices Markets Geology/Quality Transportation Environmental This, in turn, means that lower debt:equity ratios are the norm for new industrial minerals projects. INDUSTRY STRUCTURE It is hardly worthwhile to generalise about a field as diverse as industrial minerals, but there are four other structural reasons why project financing has not been widely applied. 1. The most obvious example is the predominance of small-sized operations, largely a function of transportation economics. Geological conditions also contribute to their dispersion. 2. Often, the product is only a small part of a company's business in contrast to many petroleum, metals, or coal companies whose sole business is the production of the raw material. The construction industry is a good example here for cement, gypsum, crushed stone, sand and gravel, and the drilling-mud services business for barite and bentonite. A company is unlikely to jeopardise its main business through the failure of a project financing on one of its key inputs. The corrollary is that the mined input is often regarded as a cost centre and not run on the sort of economic basis suitable for project financing. 3. There may be a reluctance to reveal key aspects of an industrial minerals venture to an outsider for purely competitive reasons. Unlike the other minerals industries which readily share technical information at plant visits and

Jan 1, 1985

By Neville J. Price

In order that the reader may not be misled, I feel it necessary to comment upon the title of this paper. "Laws of Rock Behavior," one may take as being part of the all-embracing "Law of Nature" and this, according to the Oxford Dictionary, relates to the principles of conduct recognized as being pleasing to God. I feel it would be presumptuous to erect a code of rock behavior on this basis, so turn to a secondary definition, namely that a "Law" is that which is intrinsically reasonable. It is extremely unlikely that any group of geologists, or workers in rock mechanics would be in complete agreement about what could be taken to be "intrinsically reasonable." Therefore, this paper does not present any deified utterances, but rather deals with a few aspects of rock behavior which I consider to be intrinsically reasonable and with which I hope the reader will concur. The mode of behavior of rocks in the Earth's crust covers the range from wholly brittle to completely ductile ; with a deformation time scale which may be measured in milliseconds, for some events such as meteoritic impact, or in millions of years for the tectonic deformation involved in mountain building. A complete survey is, of course, outside the scope of an introductory paper, so I must be both brief and selective in my treatment. Any attempt to establish the mode of rock behavior in the Earth's crust should take into account data and relationships established in laboratory experiments and correlate these with field evidence. Consequently, the first section of this paper presents a brief discussion of the experimental aspects of rock mechanics which are pertinent to the subsequent discussion.

Jan 1, 1970

By T. Watanabe, S. Karashima, H. Oikawa

Creep tests of a! iron and its solid-solution Fe-Mo, Fe-Co, and Fe-Si alloys with bcc structure were conducted under constant stresses in ferromagnetic and paramagnetic temperature regions above 0.5T,(T, is the absolute melting temperature). It was found their high-temperature creep behavior changed in the vicinity of the magnetic transformation temperature, that is Curie temperature, TC. In the ferromagnetic region below the steady-state creep rates were lower than those expected from the extrapolation of the data in the paramagnetic region, the amount of decrease being affected by solute addition. Also, activation energies for steady-state creep were different in the two temperature regions. The observed changes were concluded to be due to the effect of ferromagnetism on diffusion. It is well-known that plastic deformation of metals and alloys in the temperature region where mobility of atoms becomes high enough is controlled by atomic diffusion." Many experimental results394 on fcc and hcp materials have been reported to confirm this view. In bcc metals and alloys, not much basic investigation of creep deformation has been performed. In particular, experimental work on iron5-&apos; and its alloys, covering a quite wide temperature range is extremely scarce. On the other hand, the effect of ferromagnetism on diffusion has recently been demonstrated in a iron and its alloys;&apos; it has been made clear that diffusion rates in ferromagnetic temperatur~e region are significantly lower than those expected from diffusion measurement in the paramagnetic region. Therefore, it is concluded that the magnetic effect influences the high-temperature creep behavior in a! iron and in its alloys. The present authors have conducted creep experiments on a iron and its solid-solution alloys over a very wide temperature range, and have demonstrated the magnetic effect. A part of the result has already been reported elsewhere.26 In this paper, the experimental results will be described in detail. While the manuscript was in preparation, a similar magnetic effect on creep deformation of a iron was reported by Ishida . Though their experiments covered an extremely wide temperature range, the creep stresses varied from several thousand psi to several ten thousand psi with decreasing temperature. Consequently, it may be said that there remain some questions concerning their results. I) EXPERIMENTAL PROCEDURE The materials used in the experiments were pure iron and its alloys; they were prepared by vacuum melting (10"" mm Hg) electrolytic iron (99.9 pct), molybdenum powder (99.9 pct), ultrapure silicon, and cobalt pellet (99.5 pct) in alumina crucibles. The ingots were hot-forged to plates 10 mm thick and 50 mm wide, and then were hot-rolled at about 700°C into sheets 1 mm thick. Creep specimens, 5 mm in width and 15 mm in gage length, were machined from the sheets. They were annealed at temperatures which were well above their respective recrystallization temperatures. The chemical compositions of the metal and alloys are shown in Table I together with their heat treatments. High-temperature creep tests by the use of a lever-type creep testing machine were carried out in argon atmosphere under constant tensile stress. In order to keep &eep stress constant within about *0.5 pct, stress change due to specimen elongation was compensated by tensile force of a stainless-steel bellows which was inserted between the loading lever and lower specimen grip with the assumptions of a linear relationship between change in cross section and strain and uniform strain along the section. Beyond the limit of compensation by the bellows, small amounts of load were removed after appropriate strains. The testing temperatures were maintained to within i2"C of the reported values. Creep deformation was auto-graphically recorded at the upper (moving) specimen grip using a linear differential transformer which was held by a stainless-steel rod mechanically connected to the lower specimen grip. It was also directly measured with a dial-gage reading to -& mm. 11) EXPERIMENTAL RESULTS AND DISCUSSION 1) Creep Curves of a Iron and Its Alloys. Creep curves of a! iron, Fe-Si, Fe-Co, and Fe-Mo (<2 at. pct Mo) alloys usually consisted of three stages, that is transient (primary), steady-state (secondary), and accelerating (tertiary) stages. An example is illustrated in Fig. 1 for a! iron. However, in Fe-Mo alloys with more than 2 at. pct Mo, an inverse transient creepZ8 was observed as indicated in Fig. 2. The inverse behavior, which varied with the amount of molybdenum, may be due to the substructure* in the annealed specimen as was sug-

Jan 1, 1969

By Wilson B. Emery

The Hidden Dome gas field, situated in Washakie County, Wyoming, was discovered Sept. 26, 1917. Subsequently five additional gas wells were completed and a large reserve was developed. For a number of years this field completely supplied the domestic market at Basin and Greybull, as well as the refinery at the latter town, and it is still supplying gas in small amounts to this market. Production is obtained from the sands of the Frontier formation at depths ranging from 1000 to 1500 ft. The original rock pressure was 725 Ib. and initial production ranged from 4,000,000 to 28,000,000 cu. ft. per day per well. Porosity of the sand, determined from the size of the productive area and the amount of gas recovered, is over 18 per cent. Area and Management It is estimated that the productive area is about 640 acres. Its outline is indicated on Fig. 5, on which are also shown the locations of holes drilled on the structure and the area of unit operation. The unit area is owned by the Ohio Oil Co. and development and operation have been by this company. No productive well has been completed outside this area. The entire area was Government land filed on under the placer mining law. Results of Unit Operation With six producing wells, or an average of one to each 160 acres, the pool is completely developed. Location of the wells was made with respect to structural conditions plus the requirement that at least one well be drilled on each 160-acre placer claim. Perhaps a somewhat more uniform spacing of the wells might have been accomplished and one well eliminated, but it must be borne in mind that the holes, on account of their shallow depth, were not expensive and that the object was to develop as reliable a reserve as possible. There is no cause to suspect that these holes have not adequately drained the reservoir and there is every reason to think that any additional wells, which might have been drilled under diversified ownership and operation, would have been an economic waste. Unit operation by a competent company has not only resulted in the elimination of loss of gas through careless development and operation

Jan 1, 1930

By C. J. Osborn

In oral discussion at the Columbus midyear meeting, September 26, 1949, these pertinent questions were asked: Was a satisfactory separation of metal and matte obtained? The matte was quite fluid and in most cases the separation was satisfactory. Were the mattes chlorinated after aging? The mattes were stored in sealed glass mason jars, and chlorina-tion experiments made after standing for several weeks gave satisfactory results. Was ferric chloride volatilized? Most of the iron content of the matte was converted to ferric chloride. However, because of the low chlorination temperatures used (150" to 250°C) the major part of the ferric chloride remained with the residue. Undoubtedly, some ferrous chloride was also formed, because of the reducing conditions within the reaction vessel, but no effort was made to separate it from the ferric chloride. Could the reaction be stopped before making metallic iron? No attempt was ever made to stop the reaction before making metallic iron. Generally, 20 to 60 pct of the iron in the charge was obtained as metallic iron which could be readily separated from the matte. In certain cases, metallic iron was dispersed through the matte in the form of globules, which could be removed by magnetic separation. Could other sulphides, i.e., calcium sulphide or sodium sulphide be used in place of iron sulphide? No other sulphides were investigated. It was felt that titanates of calcium and sodium would be formed should these sulphides be used to replace the pyrite. What were the sulphur volatilization losses during matte smelting? In the course of this laboratory investigation, a rather wide variety of variables was introduced from highly oxidizing to reducing conditions and various ratios of pyrite, rutile, and coke. These and other factors all have a definite bearing on the sulphur losses. In general, the higher the sulphur in the charge the higher were the sulphur losses and the percentage of titanium in the matte decreased. With sulphur additions more nearly the theoretical amount, the sulphur losses averaged approximately 10 to 15 pct. With a higher percentage of sulphur on the charges, the losses were in the order of 15 to 30 pct.

Jan 1, 1951

By H. J. Struth

The benefits of proration of oil production were perhaps more concretely realized in 1932 than at any time since the oil industry adopted nation-wide production control. Reduced output of crude petroleum, which brought the daily average of the United States down to approximately 2,000,000 bbl. from a peak in 1931 of more than 2,600,000, had a telling effect on the trend of oil prices. Mid-Continent crude was advanced in price from 776, for 36-gravity oil, to $1.04 a barrel. California crude, of 26-gravity at Signal Hill, moved forward from 736 to 976 a barrel. Pennsylvania crude, the only exception to the upward trend, rose in price from $1.82 per barrel to $2.02, only to react to $1.72. This was due to local conditions which necessitated an adjustment to overcome competition from other areas of the United States. East Texas continued to exert a far-reaching influence on the crude and gasoline market during 1932. Despite the fact that oil prices were advanced in most fields, large quantities of oil were produced in East Texas in violation of state proration orders, and sold in the market at prices considerably below official postings. This created competitive conditions in the gasoline market that were felt by all refining centers of the United States. The quantity of gasoline produced from cheap East Texas crude was not large, but the volume was sufficient to influence prices in practically all sections of the country. Thus, while the industry&apos;s&apos; economic situation showed visible improvement statistically, the unreported and unseen statistics originating in East Texas proved to be an insurmountable obstacle to the economic betterment that was otherwise apparently justified. Somewhat surprising to many was the fact that gasoline consumption was maintained within 10 per cent of the preceding year. Domestic consumption showed only a net decline under 1931 of about 8.5 per cent; exports dropped in volume to the extent of about 23 per cent. As a matter of fact, domestic gasoline consumption was only about 1.4 per cent less than it was in the predepression year of 1929. Exports, however,

Jan 1, 1933

By T. F. Witherbee

Discussion of Mr. Baker&apos;s paper, read at the Lake Superior Meeting, September, 1904. MR. T. F. WITHERBEE, Durango, Mexico (communication to the Secretary*) : Mr. Baker&apos;s paper is very instructive in that it shows how furnace-derangements sometimes originate from apparently slight causes. In 1896 a similar burning through of the lining occurred at the Mayville furnace of the Northwestern Iron Co., Mayville, Wis., in exactly 38 days from the time the furnace was blown in. At that time I attributed it to the fact that the bell was carried several inches to the front side of the furnace, the length of the versed side of the arc described by the lever, thus dumping a little more of the charge on the back side, which made the front side of the furnace-charge more open and consequently increased the circulation of the furnace gases through it. After reading Mr. Baker&apos;s description, I believe that possibly a little more ore was charged on the back side of the hopper, due to the fact that it was nearest to the elevator. This unequal charging, however, was unconsciously done, as the fillers were both honest and faithful. The illustration of the burned lining of Furnace No. 1, given in Fig. - of Mr. Baker&apos;s paper answers very well for the Mayville furnace. It shows that in both cases the destruction of the lining was largely due to faulty construction, in that there were no cooling-plates in the angle of the bosh and in one or two courses of brick above it, where I believe they are-more in demand than anywhere else in the furnace. The presence of these cooling-plates at the angle of the bosh would have obliged the current of the hot gases to turn the corner and would have prevented them from following the angle of the bosh com¬pletely through the lining and shell.

Mar 1, 1905

By Roland J. Lapee

A history of the progress made in copper refining in Montana is presented. The casting furnaces and the newly rebuilt electrolytic refinery are descmbed and operating details are given. Experiences with various addition agents, effects of rernoval of chlorine from the electrolyte, and effects of separan on electrolyte and on copper deposit are discussed. Observatzons are made on the effect of various impurities in anode copper and behavior of thezr salts in electrolyte and in slime, on treatment of slime for removal of copper, and on electrolyte puriification problems. The improved method for production of starting sheets is described. Attention is given to new materials for construction and to improvement in matrials handling ad quality control. COPPER refining at Great Falls, Montana, dates back to 1892. The original plant produced 65,000 lb. of cathodes per day at a current density of 16 amp per sq ft. In this plant anodes and cathodes were handled to and from the cells by means of hand-operated chain blocks and were moved about the plant by hand trucks. Cathodes were melted in coal-fired, reverbera-tory furnaces, were charged by hand, and refined copper was dipped by hand and cast in iron molds. In 1916, a new, modern plant with capacity to refine 18 million Ib. copper per month was built. Two refining furnaces were built, and each was provided with a twenty-mold Clark casting wheel. In 1922, the furnaces were converted to the use of pulverized coal: in 1923, to the use of oil; and in 1928, to the use of natural gas. In 1926, the plant was enlarged 50 pct. The use of pulverized coal for refining copper at Great Falls was discussed1 in a paper presented at the Salt Lake City meeting of the Institute in September 1925. Also, a comparison of the use of various fuels in copper refining furnaces was discussed 2 in a paper presented at the New York meeting of the Institute in February 1932. Prior to 1943 the cellroom was operated with twenty-five 720-lb. anodes and 26 cathodes per cell. Four cathodes, each weighing about 165 lb., were produced from an anode. In 1943 the weight of the anode was reduced to 460 lb., and two cathodes, each weighing about 190 lb., were produced from an anode. In 1949, a Billet Casting Wheel for the production of 3 in. diam phosphor deoxidized billets was built. A paper, presented at the New York Meeting of the Institute in February 1956, describes3 this plant and operation. In the electrolytic refinery, production is controlled by variation of the current density. In 1956, germanium rectifiers on a separate electrical circuit were provided for the starting sheet section so that current density could be maintained at any desired figure. Also in 1956, a program of modernization and enlargement of the Electrolytic Copper Refinery was started. This program, when completed, will raise the capacity of the Great Falls Electrolytic Copper Refinery approximately 33 pct, to 33 million lb. of cathodes per month. Furnace capacity for melting cathodes and anode scrap is ample to take care of the increased production from the electrolytic refinery. This fortunate condition came about primarily as the result of the three following changes: 1) The furnaces were lengthened 10 ft in 1922 when the fireboxes were found unnecessary for burning powdered coal. 2) Furnace life, and hence furnace capacity, was increased by the successful efforts of the Copper Refinery staff to develop a method for sanding furnace side walls and roof. 3) The natural gas being used has a very low sulfur content. As a result, it is possible to reduce time spent rabbling and poling and thus greatly increase tons per furnace charge. TANKHOUSE AND TANKS The Great Falls Electrolytic Refinery is 535 ft long by 252 ft wide. The cells are arranged in four crane bays in which are operated seven 10 ton Whiting Cranes. The old cells are in groups of ten, with circulation of electrolyte through five cells in cascade and with aisles between the groups of ten cells. The new cells are nested in groups of sixteen with no aisles, are all on one level, and have individual circulation to each cell. Present plans call for 1792 commercial cells and 128 stripper cells. To reduce confusion during the construction period, and to use the cranes, cars, and other equipment already on hand, the cells in the rebuilt section were designed to have approximately the same inside dimensions as the cells in the old part of the

Jan 1, 1962

Between July 10 and August 15, 1918, the Secretary of United Engineering Society, of Engineering Foundation, and of Engineering Council visited 17 cities which are headquarters for large numbers of engineers. His mission was to tell men in all branches of the profession about "Centralized Activities of National Engineering Societies." Stops were made at Denver, Salt Lake City, Reno, San Francisco, Sacramento, Portland, Seattle, Spokane, Anaconda, Butte, Duluth,

Jan 10, 1918

By Alec M. Crowell, J. W. Sanders

While the production of crude oil and condensate in South Arkansas increased only 1.7 per cent over the 1940 figure, complete utilization of gas produced with the oil and condensate, and heretofore wasted, was beginning to be evidenced. There were 26,229,264 bbl. of oil and condensate produced in South Arkansas during 1941, as against 25,790,380 bbl. for the year 1940. (Fig. I.) Since 1936, deep producing sands have been discovered in 18 fields and during that period only 40 per cent of the total state production has come from Upper Cretaceous formations while 60 per cent came from the Lower Cretaceous and Jurassic formations. The gas produced with crude oil and condensate from the latter formation contains large quantities of hydrogen sulphide, the maximum being 6900 grains per 100 cu. ft. in the Patton pool of Lafayette County. Gas Utilization During the latter part of 1940 and the early part of 1941, pilot plants were placed in operation to determine whether the hydrogen sulphide and deleterious material in South Arkansas gases could be removed economically. The Federal Government desired to build a large aluminum plant in the Ouachita Valley and was seeking cheap fuel for the generation of electricity. The fact that the gases were produced with appreciable quantities of crude oil and condensate made it available at a very low price, since the state&apos;s conservation law prohibits the flaring of any gas. As a result of these experiments the first large-scale unit for the processing of gases containing hydrogen sulphide was placed in operation on Sept. I, 1941. The plant is in the Magnolia oil field, Columbia County. It processes residue gas from the Shell Oil Company&apos;s gasoline plant in that field and also raw gas from the Village field, 6 miles east of the Magnolia field. The gas entering the desulphuri-zation unit is laden with approximately 1400 grains of hydrogen sulphide per 100 cu. ft. and is stripped to a content of 4 grains per 100 cu. ft. The capacity of the plant is 15 million cu. ft. of gas treated daily under a pressure of 160 lb. per sq. in. The cost of treatment, exclusive of depreciation, is appreciably less than I per 1000 cubic feet. Two other plants of much greater capacity have been announced and priorities have been granted, which should bring the total amount of gas treated to 150 million cu. ft. daily. The gas to be treated will have a maximum hydrogen sulphide content of 4500 grains per 100 cu. ft. and will be processed under a pressure of 600 lb. per sq. in. These developments are something entirely new in field practice for the industry. The fact that this heretofore wasted gas is available at very low cost has led to the location of some eight war industries within the state, in addition to the alu-minum plant. Recovery OF Sulphur The Susearch Corporation and the Southern Acid and Sulphur Co. placed in operation during 1941 pilot plants to de-

Jan 1, 1942

By Alec M. Crowell, J. W. Sanders

While the production of crude oil and condensate in South Arkansas increased only 1.7 per cent over the 1940 figure, complete utilization of gas produced with the oil and condensate, and heretofore wasted, was beginning to be evidenced. There were 26,229,264 bbl. of oil and condensate produced in South Arkansas during 1941, as against 25,790,380 bbl. for the year 1940. (Fig. I.) Since 1936, deep producing sands have been discovered in 18 fields and during that period only 40 per cent of the total state production has come from Upper Cretaceous formations while 60 per cent came from the Lower Cretaceous and Jurassic formations. The gas produced with crude oil and condensate from the latter formation contains large quantities of hydrogen sulphide, the maximum being 6900 grains per 100 cu. ft. in the Patton pool of Lafayette County. Gas Utilization During the latter part of 1940 and the early part of 1941, pilot plants were placed in operation to determine whether the hydrogen sulphide and deleterious material in South Arkansas gases could be removed economically. The Federal Government desired to build a large aluminum plant in the Ouachita Valley and was seeking cheap fuel for the generation of electricity. The fact that the gases were produced with appreciable quantities of crude oil and condensate made it available at a very low price, since the state&apos;s conservation law prohibits the flaring of any gas. As a result of these experiments the first large-scale unit for the processing of gases containing hydrogen sulphide was placed in operation on Sept. I, 1941. The plant is in the Magnolia oil field, Columbia County. It processes residue gas from the Shell Oil Company&apos;s gasoline plant in that field and also raw gas from the Village field, 6 miles east of the Magnolia field. The gas entering the desulphuri-zation unit is laden with approximately 1400 grains of hydrogen sulphide per 100 cu. ft. and is stripped to a content of 4 grains per 100 cu. ft. The capacity of the plant is 15 million cu. ft. of gas treated daily under a pressure of 160 lb. per sq. in. The cost of treatment, exclusive of depreciation, is appreciably less than I per 1000 cubic feet. Two other plants of much greater capacity have been announced and priorities have been granted, which should bring the total amount of gas treated to 150 million cu. ft. daily. The gas to be treated will have a maximum hydrogen sulphide content of 4500 grains per 100 cu. ft. and will be processed under a pressure of 600 lb. per sq. in. These developments are something entirely new in field practice for the industry. The fact that this heretofore wasted gas is available at very low cost has led to the location of some eight war industries within the state, in addition to the alu-minum plant. Recovery OF Sulphur The Susearch Corporation and the Southern Acid and Sulphur Co. placed in operation during 1941 pilot plants to de-

Jan 1, 1942

By Lawrence A. Roe

Talc, when it can be isolated as a pure mineral, has a composition of 63.36% SiO2, 31.89% MgO, and 4.75% H2O. However, as an industrial commodity, talc rarely approaches theoretical purity. Nevertheless, the impure talc products of commerce find a multitude of uses and few substitutes in many industrial applications. Minerals commonly associated with and sold together in talcose mixtures are tremolite, chlorite, dolomite, mica, and magnesite. Steatite was originally a mineralogical name applied to pure talc. In today&apos;s commerce steatite generally refers to the massive variety of talc suitable for electrical insulator manufacture. Block steatite ore can be machined into various shapes. Impure varieties of massive or block talc are still commonly referred to as soapstone. Soft massive talc, suitable for crayon manufacture, has been referred to as French chalk. It has been common practice to discuss talc, soapstone, and pyrophyllite under the same general heading. In the case of soapstone and talc, this is a natural thing since many different types of platy, soft minerals exhibiting a high degree of lubricity (commonly referred to as "slip") have been grouped together and called soapstone or talc. Further, there is a mineralogical relationship of pyrophyllite to montmorillonite and talc to hectorite. Thus, talc and pyrophyllite are sometimes referred to as clay minerals. When finely divided talc or pyrophyllite are combined with water in proportions to make a slurry, the end product does have the appearance of a clay-water mixture. Soapstone for utensils and ornaments was mined by prehistoric Indians on Santa Catalina Island, Calif. In the mid-1800s, soapstone from deposits along the western foothills of the Sierra Nevada mountains was used by white settlers for building and ornamental stone and in the linings and foundations of furnaces (Anon. 1956). Previous to 1916, the annual recorded production in California did not exceed 2000 tons. In the period 1912 to 1918, output rose sharply when the Talc City, Western, and Silver Lake mines were put into operation. From 1916 to 1935, the state&apos;s annual output of talc was in the range of 9,000 to 20,000 tons. In the mid-1930s, the use of talc in wall tile grew rapidly. In California, the production of talc grew to 63,000 tpy in 1943. The post-war building boom helped California production to grow to 120,000 tons in 1951. In 1968, production was 165,000 tons, 1969 was 145,000 tons, 1970 was 185,000 tons, and 1972 was 155,000 tons. Talc mining in New York state dates to about 1878 when a Colonel Palmer and associates opened the first commercial talc mine on the Nelson Freeman farm near Talcville, New York. In 1893, this operation was sold to the International Pulp Co. which changed its name to the International Talc Co. in 1944. Total production from seven New York mines, in 1948, was 130,000 tons. A new talc operation, the Gouverneur Talc Co. owned by the R.T. Vanderbilt Co., began operations near Balmat, N.Y., in 1948. The initial capacity of the processing plant was 200 tpd (Gillingham, 1950). Subsequent expansions have increased capacity to over 600 tpd. The Vermont talc industry began just after the start of the 20th century. Talc was discovered in the area of the present Johnson, Vt., talc mine in 1902. The American Min¬erals Co. initiated plant operations at Johnson in 1904. The Magnesia Talc Co. opened a plant at Waterbury, Vt., in 1913 (Burmeister, 1963; Trauffer, 1964) and acquired American Minerals Co. in 1923. The Waterbury mine has a long history as a producer of talc crayons. The Eastern Magnesia Talc Co. was formed in 1924 by a merger of the Eastern Talc Co.

Jan 1, 1975

By H. W. Camp

The past year has had no revolutionary change in the process of petroleum refining, although there have been improvements and developments in practically every phase of operation, due largely, perhaps, to economic pressure. A few years ago, a Mid-Continent skimming plant using 35 gravity crude obtained 28 per cent. gasoline and naphtha; 9 per cent. kerosene, and the remaining yield gave gas oil and fuel oil. Figuring manufacturing cost, but not including sales, transportation, overhead and depreciation, the realization was $1.45 per bbl. of crude. Today, a thoroughly modern and up-to-date skimming plant, having all latest equipment, shows a realization of $1.74 per bbl. on the same basis. Thus it is evident that progressive developments have taken place in the last 2 or 3 years when potential earnings have been increased about 20 per cent. The average refiner is compelled to exert his utmost ingenuity in order to operate with a profitable margin. He has two factors to consider—recovery of maximum yields of profitable oils and the reduction of operating expenses. For the past 8 years, the margin between price of gasoline and cost of crude has grown narrower, constantly. Both these prices are determined by external conditions and not by the refiner himself, but the refiner might have been able to increase that margin had he more carefully controlled his output, limiting his production of light oils to current consumption. Be that as it may, this same economic pressure has given impetus to progress in improvements of primary distillation equipment, including stills, towers and heat-saving devices. A pipe still and bubble cap fractionating equipment can now replace a battery of shell stills, giving better yields, better control, elimination of rerunning and lowering of operating costs. The most recent pipe stills are being equipped either with radiant-heat furnaces or air-preheating systems and improved heat exchange equipment. These can be operated on a fuel consumption as low as 1 per cent. of the charge as compared to a fuel consumption of

Jan 1, 1929