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By S. R. Maloof

In 1945, Hollomon' showed that after plastic yielding and prior to necking under simple tension, both ferrous and nonferrous materials are approximated by an equation of the following form: where, a = true stress K = strength coefficient 5 = true strain n = strain hardening exponent If a material is stress free, a plot of log o vs log 6 would be expected to be a straight line, the slope of which is the strain-hardening exponent (n) and the intercept on the ordinate axis for 6 = 1. is the logarithm of the strength coefficient K. It can be easily shown that the strain-hardening exponent in the above equation is equal to the total uniform elongation prior to necking. Thus, one can determine the total uniform elongation prior to necking from such a plot and, as pointed out by C. W. MacGregor, 2 it is the amount of strain prior to necking which determines the extent to which a material may be deep drawn. In the view of the current interest in the fabrication of beryllium shapes, it was thought that a knowledge of the strain-hardening exponent of cross-rolled beryllium sheet would be of general interest. Load-strain data after yielding and prior to necking was taken from the work of Greenspan,3 converted to true stress and true-plastic strain, and plotted on log-log paper as shown in Fig. 1. The value of Young's modulus E for beryllium was taken as 43 . l06 psi. The slope of this plot gave a value of 0.212 for the strain-hardening exponent (n) and the intercept on the ordinate axis a value of 105,000 for K. The total uniform elongation is thus 21.2 pct, in excellent agreement with the value estimated by Greenspan (about 20 pct). Furthermore,

Jan 1, 1960

By Gerald Edmunds

THE liquidus line on the phase diagram for temperature versus composition of a binary alloy system, representing the boundary between the homogeneous melt and the heterogeneous melt plus solid, besides showing the minimum casting temperature, is useful in determining eutectic compositions and the presence of phase changes such as peritectic transformations and intermetallic compound formation. The liquidus often is determined by the cooling curves of thermal analysis, but supercooling frequently occurs, so that the temperature values are low. An alternative method, the one employed here, consists of determining the com- position of samples of the melts from heterogeneous alloys that are at equilibrium. With meticulous attention to fundamentals, this method is capable of yielding values limited in precision only by the temperature control and measurement and analyses. APPARATUS By starting, on the one hand, with a supersaturated solution and allowing the excess solute to precipitate, and on the other hand with an undersaturated solution and allowing more of the solute to be dissolved, both processes being carried out at the same temperature, equilibrium may be said to have been approached from both directions; that is, from above and from below. If the analyses show the solutions to contain the same fraction of solute when equilibrium has been approached from above and from below, one is assured that equilibrium has been reached in both determinations. In order to carry out such determinations, it is necessary to have equipment for obtaining and maintaining the proper temperatures; for holding the melt, measuring its temperature, and stirring, sampling and analyzing it. The present work required temperatures from 420° to 900°C. The equipment consisted of: A furnace, which was a vertical alundum tube, 1 ¾ in. diameter inside and 18 in. long, wound with Nichrome resistance wire, surrounded by a 3-in. i.d. alundum tube wound for 5 in. of length near each end, for compensation of end losses. This muffle was contained in an iron shell with Transite end plates, the intervening space being packed with Sil-O-Cel. The outside dimensions of the furnace were 12 in. in diameter by 18 ½ in. in height. Heating current was supplied by three independent variable-voltage transformers (Variac), one connected to each end compensator winding and manually controlled, and one connected to the main winding through a series resistance of 5 ohms. This resistance was short-circuited for

Jan 1, 1944

By A. R. Jr. Amos

LOG washers have been used for many years in the washing of clay iron ores, phosphate rock and manganese ores, but not until the past 15 years have they been employed to any extent in the preparation of aggregate materials and fluxing stone. For a machine of such importance where tenacious clay or soft rock must be eliminated, there are few data generally available. The purpose of this paper is to set forth the results obtained from several operations, together with a few suggestions for planning a specific installation. Where the material to be washed out consists of loose surface soil, silt, or small amounts of quickly soluble clay, there is little competition with other forms of washers, because greater power and maintenance are required for the operation of log washers, but where the foreign matter is a stiff clay, such as occurs with high-calcium limestones and in marginal gravel deposits, the ability of other kinds of washers to eliminate com-pletely the hard clay balls is at least uncertain. Then the log washer comes into its own field, for with the breaking and churning action of the logs it will clean out the toughest clay. Even with material from the hydraulic dredge, if it contains tough clay, the log washer is desirable unless the gravel is subjected to a costly soaking and rehandling process. Recently there has been a considerable development in other types of machines to accomplish these results but it is not within the scope of this paper to make comparisons between competitive types, but to present the best obtainable data on log washers only. From the primitive design that gave it its name, a long log hewn from a tree, with paddles forged to shape from strap iron and attached by lag screws, the log washer has gradually been developed to the present all-steel type. As now manufactured, the log washer consists essentially of two built-up logs on which are mounted a series of paddles, carried by shafts fitted at the ends of the logs on bearings fastened outside the enclosing steel box, or trough, which is set at an angle of about 5° to 10° and into which the material is fed. Stuffing boxes at the places where the shafts pass through the box at the lower end are equipped with water-

Jan 1, 1936

By Thos Gibson

THE object of taxation is the raising of a revenue. Unless a tax accomplishes this, it is a failure. The right to take for public purposes a part of the moneys obtained from the carrying on of private enterprises is an attribute possessed only by a lawful government, and may indeed he called the supreme attribute of government. In free, democratic communities this power must of necessity rest upon the consent of the governed. Power implies obligation, hence it is obviously the duty of a government, in framing a system of taxation, to provide one which, while effective in producing a revenue, is also just and impartial. It will be conceded that mines and mining property ought to bear a fair share of the public expenditure. The question is, upon what basis taxation should proceed. Two separate taxing principles are usually contended for: Taxation should be proportionate to the benefits received by the person or property taxed; taxation should be based on ability to pay. A third is sometimes added, taxation should have reference to the extent and value of the natural resources enjoyed. As applied to mining taxation, it is pointed out by those who support the first mentioned basis that, mines being usually situated in rocky and hence sparsely peopled regions, mining companies are frequently obliged to construct roads, railways, telegraph and telephone lines, schools, water and sewerage systems, and many other amenities and conveniences of civilization, the cost of which in regions better suited for agriculture and consequently more thickly populated, has either been defrayed locally, or can be spread over a sufficiently large taxable group of people to materially lighten the financial burden on the mine. The mining com¬pany, it is argued, having made these outlays, should receive credit for, them and be relieved of taxation to a corresponding extent. There may be some force in this contention, but the situation is capable of relief without attempting to place taxation upon so unworkable a basis as the value of benefits received. Who is to be the judge of these benefits, and how are they to be valued? The very existence of a mining company and its ability to carry on business in peace and security, depend on the prevalence of law and order, which is a result of good government. The state provides protection against violence, and courts of law for

Jan 4, 1919

By M. B. Standing, D. L. Katz

Equilibrium data are reported on the composition and densities of coexisting vapor and liquid phases as a function of Pressure and temperature for four hydrocarbon systems prepared from crude oil and natural gas. The data were observed over a range of pressures from 1000 to 8220 Ib. per sq. in. and at temperatures ranging from 35' to 250°F. The compositions of the hydrocarbon systems were such that the critical temperatures of the mixtures were lower than the range of the investigation. Under these conditions, it is shown that the composition of the systems has a marked effect upon both the absolute value of the equilibrium constants and the change of the constants with pressure for the several components comprising the system. From weight-balance considerations, it has been possible to construct the partial phase diagram of a mixture of a 49.9" A.P.I. crude oil and natural gas having a gas-oil ratio of 3660 cu. ft. per barrel. Descriptions of the apparatus used, the analytical procedure, the material used, and the equilibrium measurements are included. A knowledge of the physical behavior of naturally occurring hydrocarbon mixtures is fundamental to the treatment of many problems in the production, transportation and rehing of petroleum. The recent discoveries of pools having formation pressures up to 7500 lb. per sq. in. and higher, and the development of full-scale equipment to operate at pressures of 5000 lb. per sq. in. or more have greatly increased the need for knowledge of the composition, temperature, pressure and density relationships of coexisting vapor and liquid hydrocarbon phases. The following paper presents the results of investigations upon 22 mixtures of natural gas and crude oil of known com~o~itio~ that had been brought to equilibrium under controlled conditions of temperature and pressure. Data are presented upon the densities and compositions of the coexisting vapor and liquid phases for four different systems containing hydrocarbon material having boiling points from minus 2 5S°F. to well over I000 F. The data were observed Over a pressure range from Iooo Ib. per Sq. in to 8220 lb. Per sq. in. and a temperature range from 35' to 2 50°F. The accepted method of computing the physical relationship between two coexisting phases of a hydrocarbon mixture is by use of the "equilibrium constant" K as proposed by Souders, Selheimer, and Brown. definition,

Jan 1, 1944

By M. B. Standing, D. L. Katz

Equilibrium data are reported on the composition and densities of coexisting vapor and liquid phases as a function of Pressure and temperature for four hydrocarbon systems prepared from crude oil and natural gas. The data were observed over a range of pressures from 1000 to 8220 Ib. per sq. in. and at temperatures ranging from 35' to 250°F. The compositions of the hydrocarbon systems were such that the critical temperatures of the mixtures were lower than the range of the investigation. Under these conditions, it is shown that the composition of the systems has a marked effect upon both the absolute value of the equilibrium constants and the change of the constants with pressure for the several components comprising the system. From weight-balance considerations, it has been possible to construct the partial phase diagram of a mixture of a 49.9" A.P.I. crude oil and natural gas having a gas-oil ratio of 3660 cu. ft. per barrel. Descriptions of the apparatus used, the analytical procedure, the material used, and the equilibrium measurements are included. A knowledge of the physical behavior of naturally occurring hydrocarbon mixtures is fundamental to the treatment of many problems in the production, transportation and rehing of petroleum. The recent discoveries of pools having formation pressures up to 7500 lb. per sq. in. and higher, and the development of full-scale equipment to operate at pressures of 5000 lb. per sq. in. or more have greatly increased the need for knowledge of the composition, temperature, pressure and density relationships of coexisting vapor and liquid hydrocarbon phases. The following paper presents the results of investigations upon 22 mixtures of natural gas and crude oil of known com~o~itio~ that had been brought to equilibrium under controlled conditions of temperature and pressure. Data are presented upon the densities and compositions of the coexisting vapor and liquid phases for four different systems containing hydrocarbon material having boiling points from minus 2 5S°F. to well over I000 F. The data were observed Over a pressure range from Iooo Ib. per Sq. in to 8220 lb. Per sq. in. and a temperature range from 35' to 2 50°F. The accepted method of computing the physical relationship between two coexisting phases of a hydrocarbon mixture is by use of the "equilibrium constant" K as proposed by Souders, Selheimer, and Brown. definition,

Jan 1, 1944

By B. D. Thomas

When the origin and early plans, of Battelle Memorial Institute were described in this journal in October 1929 by R. W. Gillett the first director, the doors of the laboratory had just been opened and the hope of the founder that the institution serve the world by research for industry still existed only as an ideal in the minds of the thirty or so employees who then constituted the staff. Since that time the country has experienced troublous times. A devastating depression plunged the entire world into an unprecedented period of financial and industrial inactivity; and the slow recovery of the late thirties was soon to be overtaken and overwhelmed in the violence of war. Through this time of stress Battelle has continued to grow. The staff has increased to almost 600; buildings and equipment have been added, until now it stands in a place of pre-eminence in the metallurgical and engineering world.

Jan 1, 1944

By A. R. Jr. Amos

LOG washers have been used for many years in the washing of clay iron ores, phosphate rock and manganese ores, but not until the past 15 years have they been employed to any extent in the preparation of aggregate materials and fluxing stone. For a machine of such importance where tenacious clay or soft rock must be eliminated, there are few data generally available. The purpose of this paper is to set forth the results obtained from several operations, together with a few suggestions for planning a specific installation. Where the material to be washed out consists of loose surface soil, silt, or small amounts of quickly soluble clay, there is little competition with other forms of washers, because greater power and maintenance are required for the operation of log washers, but where the foreign matter is a stiff clay, such as occurs with high-calcium limestones and in marginal gravel deposits, the ability of other kinds of washers to eliminate com-pletely the hard clay balls is at least uncertain. Then the log washer comes into its own field, for with the breaking and churning action of the logs it will clean out the toughest clay. Even with material from the hydraulic dredge, if it contains tough clay, the log washer is desirable unless the gravel is subjected to a costly soaking and rehandling process. Recently there has been a considerable development in other types of machines to accomplish these results but it is not within the scope of this paper to make comparisons between competitive types, but to present the best obtainable data on log washers only. From the primitive design that gave it its name, a long log hewn from a tree, with paddles forged to shape from strap iron and attached by lag screws, the log washer has gradually been developed to the present all-steel type. As now manufactured, the log washer consists essentially of two built-up logs on which are mounted a series of paddles, carried by shafts fitted at the ends of the logs on bearings fastened outside the enclosing steel box, or trough, which is set at an angle of about 5° to 10° and into which the material is fed. Stuffing boxes at the places where the shafts pass through the box at the lower end are equipped with water-

Jan 1, 1936

By Oliver Bowles

DISCUSSIONS of trade and commerce are generally more comprehensive today than in the past; the problems are approached with a vision unrestricted by national boundaries, and broad enough to comprise the entire world. The extent to which the limited viewpoint that has characterized past ages is yielding to an economy of world-wide scope is exemplified by the Atlantic Charter which blazes a trail in the direction of trade principles that aim to preserve the interest of each individual country in the commonwealth of nations. Its fourth article promulgated the principle that all nations should have access on equal terms to the trade and to the raw materials of the world which may be needed for their economic prosperity. Future developments in reciprocal international trade may have some effect upon the flow of nonmetallic minerals but such effects are not likely to be great because tariffs and trade policies have not affected that flow profoundly in the past. Nevertheless conditions may change and new problems may arise demanding important decisions. Sudden changes are not to be expected, but rather an orderly evolution in which national interests will merit due consideration in establishing broader policies.

Jan 1, 1945

By J. R. Long, T. R. Graham, R. S. Dean

FOLLOWING the development of elec¬trolytic manganese production by the Bureau of Mines, an extensive program was planned to study the character of this high-purity product and its possible utilization in various alloy combinations. Previous work reported in the literature concerning alloys containing substantial amounts of manganese dealt largely with material prepared from relatively impure grades of the metal, and in many instances the impurities thus introduced did not permit true evaluation of manganese as an alloying element. One phase of the Bureau's program included a general review of the system and the establishment of the physical properties of copper-manganese-zinc alloys, using electrolytic manganese, and with particular emphasis directed to com¬positions within the alpha solid solution area. A number of reports of the work on alloys in this system, giving specific data concerning the equilibrium system and some of its alloys, have already been published. One study1 established the alpha solid solution area at various temperature levels and composition ranges up to 50 pct manganese. Other investigation reports presented the properties of selected alloys; namely, a 65 pct copper, 10 pct manganese, 25 pct zinc alloys' a sensibly white manganese brass composed of 70 pct copper, 20 pct manganese, 10 pct zinc,3 and a series of alloys with a constant copper content of 60 pct and 5 to 25 pct manganese, balance zinc.4 In these reports tensile properties as influenced by cold-working and subsequent annealing were given in detail. Additional data are now available on other alloys of the alpha region up to 50 pct manganese, and these, together with previously published information, are sufficiently complete to establish the relationship between properties and composition for this portion of the ternary system. The present report is a summary of the tensile properties of wrought alloys in the form of sheet and rod stock. The summary is necessarily limited to data for only one condition of cold-work and a single annealing temperature, since a complete exposition of all the data available would be too extensive for this presentation. Nevertheless, it is possible to make a reasonable approximation of the tensile properties in other conditions of cold-working and annealing by a correlation of the data previously presented on specific alloys and the data given here.

Jan 1, 1947

By R. W. Nash, A. E. Schwaneke, V. R. Miller

The Bureau of Mines developed a detector for controlling sorting devices to separate the copper-bearing fragments from the barren portion of Michigan native copper and western prophyry copper ores. A successful sorter could be used to preconcentrate the ore and eliminate costly hoisting or hauling of waste. An induction balance unit was developed and used in sorting tests on crushed sized - 2.5 + 1. 3-cm (- 1 + 1/2- in.) ores from the Kingston (0.9% Cu) and Centennial (1.6% Cu) mines of Upper Michigan. Concentrates of 4.0% and 7.5% Cu, respectively, were obtained at recoveries of 85 and 80% of

Jan 8, 1978

By E. W. Engelmann

RAPID progress has been made during the past year in the copper mills throughout the country. Particular efforts have been made to increase the fine-grinding efficiency by the installation of larger classifying units operating in closed circuit with ball mills, such as the 78-in. high-weir Akins installation at the Phelps Dodge plant at Ajo, Ariz.; also the Type "FX" Dorr classifiers of Nevada Consolidated at McGill. Nev. and the "FX" Dorr bowl classifier of the Braden Copper Co. in Chile. Some of the copper milling plants in the Southwest, such as Chino in New Mexico and Ray Con. in Arizona, have replaced rolls operating wet in their fine-grinding circuit by rod mills. At Hollinger primary rod mills were formerly used in open circuit followed by pebble mills in closed circuit with classifiers. They now have primary ball mills in closed circuit with large extra heavy classifiers and no secondary mills. This new installation is producing the same grinding on 5000 tons per day with a reduction in cost of nearly 4c. per ton. At the Braden plant, in Chile, short-head Symons crushers have replaced 54-in. rolls, thereby in- creasing crushing capacity with some saving in maintenance cost.

Jan 1, 1939

By H. R. Spedden

As part of its broad program of educational assistance-including grants, fellowships, and scholarships -Kennecott Copper Corp. offers summer employment opportunities for college students at each of its operations. Originally, summer job programs were intended primarily to help students defray their educational expenses. But as the nation's economy expanded with increased production and a growing demand for well-trained engineers, summer employment became an important means to help qualify future professionals and fill industry's need for them. Both the employer and the student thus derive benefits from such training.

Jan 6, 1967

By Hans Lundberg

AFTER the war years, great activity has been shown in geophysical exploration for ore. The appreciation by mining and government geologists of geophysical techniques and results is largely responsible for the popularity of these methods. In Canada, plans are being made to study, by geophysical methods, the structure of a portion of the Pre-Cambrian shield in the hope that such studies will not only give a clearer picture of the geology, but will be of direct aid to the mining companies when selecting areas for detailed prospecting. Although geophysics thus has become more popular, some engineers are still reluctant to employ the methods to their full extent. Allotted funds are often rather low, so that the least expensive

Jan 1, 1947

By Augustus Locke

I WISH to urge on this Committee the task of evaluating mining geology. -My motive is as follows: It, is a. duty of the Institute from time to5 time, to establish the social perspective of the professions grouped within it, not simply to promote their use, but to determine with engineering definiteness their true powers and functions. This becomes the delegated duty, therefore, of this committee in respect to geology. Be- cause my own subject is mining, I shall confine my remarks to mining geology. But I believe that the evaluation should be made to include all of that geology termed economic. The perspective for such evaluation is shown in the nature of the public support given to geology. The federal Geological Survey, the leading organization on the economic side, is actuated by the zeal of a small group of devoted professionals who consider its work valuable, ' It proceeds, however, on a starvation ration of appropriations, and that implies that neither the corporations, the voters nor the vote getters consider it important. Altogether, in' the public consciousness, geology is negligible. That, at the same moment, .the profession should act with full confidence, while everyone else should act' with opposite motives, is not fitting. For us, as a committee, to remain incurious regarding such a disparity of beliefs is quite impossible.

Jan 1, 1931

By John Blatchford, H. O. Hofman

The leading antimony mineral is stibnite. In smelting stibnite ore two processes are available, precipitation and roasting-reduction. The former is suited only for high-grade ores. As low-grade ores are more common than high-grade, roasting-reduction is of greater importance than precipitation. In the roasting process the aim may be to leave the oxidized antimony in the ore, or it may be to volatilize as much of the antimony as possible, collect the volatilized oxide as a rich intermediary product and smelt it for antimony, leaving the gangue poor enough to be considered a waste product. Whichever way the roast is conducted certain difficulties inherent in stibnite are encountered. These are: 1. The low melting point of stibnite which, according to Pélabon,' is 550°C., according to Wagemann2 540°C., and according to Borgstroma 546°C. 2. The ignition temperature: According to Friedrich,4 stibnite, if heated in air, begins to oxidize at 290°C. if the size of a grain is 0.1 mm. in diameter; at 343", if 0.1 to 0.2 mm.; and 430" if 0.2 mm. 3. The fusibility of a mixture of Sb2S33 and Sb203 which in the form of kermesite (Sb2S3)z.Sbz03 melts at 517°C.6 4. The volatility of Sb2Ss and SbzOs, for which no numerical data appear to exist, although practical experience has shown that they are volatile at low temperatures. As regards the oxidation of metallic antimony, we have the experimental evidence of C. F. Plattner6 that when fused and brought to a red heat, it burns with a bluish-white flame to Sb2Oa which passes off as a

Jan 1, 1916

By William M. Brewer

Until quite recently, in fact within the past two gears, but little attention has been given to the outcrops on the west coast of Vancouver Island, and their copper-contents. During the past few months the writer has been engaged in examining and developing some of these prospects. In many respects he has found characteristics associated with these prospects which, in his experience, are unique. In the first place, nearly all the outcroppings which overlie chalcopyrite-ore along the west coast of the island are composed of a high-grade magnetite. The magnetic qualities of some of these outcrops arc so pronounced that the magnetite possesses polarity. Although the writer hinlsclf had no analyses of this magnetite made, yet from its appearance he can readily believe that analyses made for other parties, which show a yield' of 62 or 63 per cent. of metallic iron, with only traces of phosphorus and silica, are correct. At a very shallow depth, masses of chalcopyrite, yielding in some instances as high as 32.6 per cent. of copper, occur associated with the magnetite; and in one instance, which recently came under the writer's observation, a solid body of high-grade chalcopyrite, fully 4 feet in thickness, occurs Within 6 feet of ; the surface. Usually this solid sulphide-ore carries low values in gold. Probably ail average of' $2 per toil would be fairly representative. But in some instances development has determined the occurrence of narrow stringers of pyritous quartz, associated with the sulphide-ores, which yield by assay more than $20 per ton in gold. In the districts examined by the writer, the country-rock is usually crystalline limestone, with dikes of igneous rock as intrusions. Sometimes the outcrops of magnetic iron-ore are

Jan 1, 1900

By F. L. Grammer

The analyses given in Table I. were made several years ago at my request at a plant using Lake ores. They are of two furnaces, one making basic, the other Bessemer pig— they gave 6 casts each in 24 hr., also two flushes of cinder between each cast. They are offered simply for the sake of reference as, so far as I know, it is unusual to find so frequent full analyses made and none are on record. The variations in manganese-content in the first and second flushes on the basic furnace are interesting, if no more than a freak—the first flush being invariably higher in manganese. The iron-content of the two slags from an average of 12 flushes shows: Basic. Bessemer. Per Cent. Per Cent. Total iron...................................... 2.85 1.70 Combined iron................................ 0.72 0.52 Free iron....................................... 2.13 1.18 The greater iron-loss in the basic slag, while known, has never heretofore been so clearly set forth. This may modify the arrangement for handling slag; heretofore usually determined by proximity of the dumping-heap. If a nearby heap is used on contiguous territory, in the past, tilting molten-slag pots were used. If the Pittsburg flood-records for 30 years are a fair criterion the government regulations were inadequate, and molten slag was dumped in such a manner as to throttle the Monongahela at the time of the spring thaws. At Pittsburg the slag, where it is carried to a distance, is frequently granulated in pits and then removed in cars to which it is conveyed by clam-shell buckets. This practice is also quite customary where the slag is intended for the manufacture of slag cement. The production of 500 tons of cast-iron daily means about 300 tons of- slag and at 2.113 per cent. equals 6.4 tons

Jan 1, 1914

By James O. Elton

This paper covers, besides laboratory work, a study of actual operation at the Washoe Smelter over a considerable period of time, together with the results of a visit to the Midvale plant of the United States Smelting & Refining Co., near Salt Lake. For the latter privilege, as well as permission to publish the resulting data herein given, I am indebted to George W. Heintz, General Manager of the Midvale plant, and here take pleasure in expressing my appreciation for the many courtesies extended to me by Mr. Heintz and members of the technical staff at the smelter. Almost all of the world's supply of arsenic is recovered as a byproduct in the smelting of other metals. It is seen 'on the market in various forms, the most common being arsenic trioxide, the " white arsenic " of commerce, which is sold as a heavy white powder, or in white, glassy, translucent masses. The trioxide is used in the manufacture of pigment, glass, and insecticides. About 50 per cent. of the domestic consumption is supplied by imports. Statistics of Arsenic Trioxide in United States.' Production. Consumption. Price Per Pound. Year. Tons. Tons. Cents. 1907..........1.010 5.471 5 1908,.........1,302 6,098 33/4 1909,.........1,007 4,600 2 7/8 1910,.........1,526 5,428 2 1/2 1911,.........3,081 6,539 2 1912,2........ 2,926 Closed at 4 7/8 Arsenic occurs in combitlation with sulphur and the metals in a large number of minerals. It is present in small amounts in many ores. In the roasting and smelting furnaces many of its compounds break down, liberating arsenic trioxide, which is volatilized and carried by the gases into the flue system, where a part is condensed and settles with the flue dust.

Jan 1, 1914

By Theodore R. Butkovich, Jesse L. Yow

Geological storage of spent-fuel assemblies from an operating nuclear reactor has been underway since the Spring of 1980 at the U.S. Department of Energy's Nevada Test Site. The primary objective of this generic test is to evaluate granite as a medium for deep geological storage of high level reactor waste and to provide data on thermal and thermomechanical behavior of granite from imposed heat loads.(l) The underground installation in the Climax stock granite was sited at about 420 m below the surface and 145 m above the existing water table. As shown in Figure 1, three parallel drifts were excavated spaced on approximately 10 m centers. Seventeen storage holes were drilled at the central drift on 3 m centers in which eleven spent fuel canisters and six thermally identical electrical simulators were emplaced. Electrical resistance heaters were emplaced in vertical holes in the floor of the side drifts on 6 m centers. The thermal output of these heaters is being periodically adjusted to simulate the thermal response of a large storage array. Rock and ventilation air temperatures are being measured continuously in the drifts and throughout the rock surrounding the excavations. Measurements of drift deformation have been made routinely since the emplacement of the spent fuel. Both vertical and horizontal measurements are being taken at five locations along the heater drifts and at six locations along the central canister drift (Fig. 1). Two types of instrumentaton are being used: convergence wire extensometers which are monitored automatically, and a manually operated tape extensometer with which measurements are taken periodically. The tape extensometer measurements were initiated about 6 weeks following fuel emplacement. The lack of a temperature correcting capability for the convergence wire extensometers make that data unavailable for analysis at this time.

Jan 1, 1982