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By R. S. Dean

The commercial production of electrolytic manganese on a small scale commenced in 1939. The writer made a short report on the progress of production and utilization in Mining and Metallurgy for January 1941. Progress during the last two years, naturally, has been more rapid. In June 1940, Congressman (now Senator) Scrugham presented a proposal to Congress for an appropriation authorizing erection of a pilot plant for " the production of metallic manganese by electrolytic or other means." As a result of this, a pilot plant, having a capacity of a few hundred pounds per day was built at Boulder City, Nev. Subsequent appropriations permitted expansion of the plant to about a ton per day. Much has been learned in this plant about electrolytic manganese, and the product even in its small way has found war uses of considerable importance. Meanwhile, the Knoxville plant of the Electro Manganese Corporation, the sole commercial producer, was expanded to about 4 tons per day to supply needed material for the war program. Other proposals for commercial plants have not been favorably received by the War Production Board. The Bureau reported on one such proposal by the American Alloys and Chemical Corporation. Practice at BouldeR City The present practice, as carried out at Boulder City, which is being described in more detail in a current paper by the Bureau staff at Boulder City, starts with a manganese dioxide ore containing about 20 per cent manganese. Currently this ore comes from the Three Kids deposit near Las Vegas. The steps for the production of electrolytic manganese, in general, are as follows: 1. The manganese in the ore is reduced to MnO. 2. The MnO is dissolved from the ore in spent electrolyte, which contains about 38 to 47 grams per liter of free sulphuric acid, 135 grams per liter of ammonium sulphate, and 10 to 12 grams per liter of Mn as sulphate. In the leaching step the manganese is built back up to 32 to 36 grams per liter of Mn as sulphate; the pH is adjusted to neutral by means of gaseous ammonia and passed through thickeners. 3. The electrolyte is purified by adding H2S, which precipitates the heavy metals. After filtering, ferrous sulphate is added to the solution and oxidized with air and the solution is filtered and clarified on a precoat filter. 4. The purified catholyte is electrolyzed in a diaphragm cell using stainless-steel cathodes and lead-silver anodes. The current density is about 45 amp. per sq. ft. Current efficiencies of 60 to 65 per cent are regularly obtained.

Jan 1, 1944

By R. S. Dean

The commercial production of electrolytic manganese on a small scale commenced in 1939. The writer made a short report on the progress of production and utilization in Mining and Metallurgy for January 1941. Progress during the last two years, naturally, has been more rapid. In June 1940, Congressman (now Senator) Scrugham presented a proposal to Congress for an appropriation authorizing erection of a pilot plant for " the production of metallic manganese by electrolytic or other means." As a result of this, a pilot plant, having a capacity of a few hundred pounds per day was built at Boulder City, Nev. Subsequent appropriations permitted expansion of the plant to about a ton per day. Much has been learned in this plant about electrolytic manganese, and the product even in its small way has found war uses of considerable importance. Meanwhile, the Knoxville plant of the Electro Manganese Corporation, the sole commercial producer, was expanded to about 4 tons per day to supply needed material for the war program. Other proposals for commercial plants have not been favorably received by the War Production Board. The Bureau reported on one such proposal by the American Alloys and Chemical Corporation. Practice at BouldeR City The present practice, as carried out at Boulder City, which is being described in more detail in a current paper by the Bureau staff at Boulder City, starts with a manganese dioxide ore containing about 20 per cent manganese. Currently this ore comes from the Three Kids deposit near Las Vegas. The steps for the production of electrolytic manganese, in general, are as follows: 1. The manganese in the ore is reduced to MnO. 2. The MnO is dissolved from the ore in spent electrolyte, which contains about 38 to 47 grams per liter of free sulphuric acid, 135 grams per liter of ammonium sulphate, and 10 to 12 grams per liter of Mn as sulphate. In the leaching step the manganese is built back up to 32 to 36 grams per liter of Mn as sulphate; the pH is adjusted to neutral by means of gaseous ammonia and passed through thickeners. 3. The electrolyte is purified by adding H2S, which precipitates the heavy metals. After filtering, ferrous sulphate is added to the solution and oxidized with air and the solution is filtered and clarified on a precoat filter. 4. The purified catholyte is electrolyzed in a diaphragm cell using stainless-steel cathodes and lead-silver anodes. The current density is about 45 amp. per sq. ft. Current efficiencies of 60 to 65 per cent are regularly obtained.

Jan 1, 1944

By C. R. Holmgren

A large consolidated sand core was used in this investigation. Four groups of experiments including gas drives, water drives, and water drives combined with gas injection, were made. The results of the gas-drive experiments indicate that greater ultimate recovery may be obtained by higher pressure gradients. However, other considerations challenge the absolute veracity of this conclusion. Results indicate that with connate water present and a low pressure gradient during a gas drive, less gas is required to produce a given amount of oil. The saturation gradient determined during a gas drive is presented. Results of the water-drive experiments indicate that the recovery of oil is not a function of either gradient Or input rate. The presence of initial gas saturation resulted in a slightly lower final oil saturation. Injection of sufficient gas to maintain the initial gas saturation during a water drive resulted in lower final oil saturation. Introduction With the demand for petroleum products reaching an all-time record high and the location and exploitation of new reserves becoming more difficult and expensive, the oil industry must look to more thorough and efficient methods of producing the petroleum already located. Much of the previous work along these lines is exploratory and suggests a more complete investigation. For example, a great amount of laboratory work has been done on flooding sands initially saturated roo pct with oil. Since sands saturated roo pct with oil rarely, if ever, exist in nature, and because the water content is a vital factor in the ultimate recovery from the sand, laboratory investigations on cores without water must be supplemented by comparable work on cores with water present.1'2 Other investigators have done a considerable amount of laboratory work using gas and water drives.3 Krutter and Day4 have reported results of investigations using cores saturated IOO pct with oil and have concluded that " the ultimate recovery obtained, using air drive, from a completely oil-saturated core depends on the pressure gradients used. The higher the pressure gradient, the greater will be the recovery until a certain Pressure range is reached above which the reward of increased recovery is much smaller for similar increments in pressure." Yuster and Day6 conclude that less gas and less time are required to produce a given quantity of oil at high pressure gradients than at low pressure gradients; they also conclude that an increase in the viscosity of the oil requires a proportionate increase in the gas needed for recovery. Their results indicate that the gas required to produce a given quantity of oil is greatly reduced by the presence of connate water. R. C. Earlougher2 concluded, based on results of water-flooding a large number of

Jan 1, 1949

By J. W. Hickman

Most of the electron diffraction studies of oxide films which form on metals and alloys have been carried out by oxidizing the specimens in an auxiliary furnace, cooling down to room temperature and then inserting the sample in the camera and taking a diffraction photograph. Prior to the investigations at the Westinghouse Research Laboratories, no systematic study of the oxidation of any metal or alloy had been made over a wide temperature range with photographs taken at elevated temperatures except the investigation of iron by Jackson and Quarrell.' In order to interpret the electron diffraction patterns of the oxides which may form on alloys, it seemed advisable to make a comprehensive study of the oxidation of the purest metals available in the bulk form. Thus far studies have been completed on iron,2 cobalt,~ nickel,= chromium,= copper,z tungsten,s molybdenum,3 beryllium,' uranium,' thorium,' titanium6 and zirconium6 while investigations are in progress on tantalum and columbium. The next step in the study is concerned with the investigation of the oxides which form on binary alloys. Some of the alloys consist of a single phase while others contain more than one phase. The identification of the oxides on the surface of a binary alloy may be more difficult than on the metals since oxides containing both metals as well as those of each metal separately may form. Furthermore, it is possible that solid solutions of the various oxides may occur. In these cases the electron diffraction method may not be able to identify the oxidation products unequivocally. Examples of solid solutions which may present difficulties are MOO* and WOp, Fe304 and FeO.CrnOa since the diffraction patterns are so similar. Since electron diffraction can determine only the structure of the oxide, the chemical composition must be inferred from the diffraction data based upon X ray diffraction investigations of specimens of known composition. It is possible in some cases to decide whether a given solid phase reaction can occur on the surface of an alloy by a study of available thermodynamic data. Table I lists the equations for the formation of most of the oxides from the elements together with values of loglo Kg for the several temperatures. AF"B = -RT In KR AF°R and KR are the free energy and equilibrium constant of the reaction. Calculations may be made using the the given in I 1 to determine whether a given solid phase reaction is possible thermodynamically. For example, a solid phase reaction should occur between aluminum and chromium oxide to form

Jan 1, 1949

By J. Sharshall Grasty, Thomas L. Watson

The users of barite in the United States derive their supply partly from the domestic production and partly from the imports from foreign countries. According to the Mineral Resource division of the U. S. Geological Survey, the domestic production of barite in 1913 was 45,298 short tons, valued at $156,275, or $3.45 a ton, and the imports of crude barite were 35,840 short tons, valued at $61,409, or $1.71 a ton. These figures clearly show a decided advantage in cost of the foreign over the domestic barite to users in the United States. The difference in cost is the only advantage to the consumer of foreign barite, for there are large reserves of the mineral in the United States of good grade. The production of many of the operating mines is capable of decided increase, and it is believed that the operating mines together with the large reserves of undeveloped deposits of barite are entirely adequate to meet the demands of the users in the United States. Deposits of barite are known in California, Idaho, Nevada, and Alaska, but most of them are undeveloped because there is, apparently, no market for the material in that region. The domestic production is derived from Missouri .and the Appalachian States, the greater part being obtained from Missouri. Following the outbreak of war in Europe many users of foreign barite in the United States have been forced to seek their supplies at home. It seems opportune at this time, therefore, that a general review be given of the barite industry in the Appalachian States, one of the two areas from which the domestic supply of the mineral is derived, and that attention be directed to the undeveloped deposits in the region. Briefly, then, this paper reviews the barite industry in the Appalachian States, and describes the occurrence, preparation, and uses of the mineral. General Character Barite, known commercially as barytes or heavy spar, is barium sulphate (Baso4), containing when pure BaO, 65.7 per cent., and S03, 34.3 per cent. The specific gravity is 4.3 to 4.6, and the hardness 2.5

Jan 1, 1915

NEW MEMBERS The following list comprises the names of those persons who became members during the period May 10 to June 10, 1914. Members ABE, ASAKA, Chief Min. Engr., Yamagano Gold Mine, Satsuma-Gori, Satsuma, Japan. ANDERSON, FRANK M., Geol Cartagena Refining Co., Cartagena, Colombia, S. A. BACON, MAURICE W., Genl. Mgr Stewart Mining Co. Butte, Mont. BACON, RAYMOND F., Chem Director, Mellon Institute, Pittsburg, Pa. BAKER, HAMILTON WALLACE, Min. Engr Fernley, Nev. VON BAYER, AUGUST HECTOR, Supt Kentucky Solvay, Coke Co., Ashland, Ky. BISHOP, WHEELER SCOTT, Research Chem Care Braden Copper Co., Rancagua, Chile, S. A. BOWEN, CHARLES GILMAN, Timekeeper 208 School St., Grass Valley, Cal. BOYER, SAMUEL L., Mine Operator, Mgr., Mike. Horse Min. Co., W. 2808 Boone Ave., Spokane. Wash.

Jan 7, 1914

By Donald K. Weaver

THERE have been eight different oil zones identified and produced at Santa Fe Springs, of which three or four are in turn divided into two or three parts. These zones are, from top to bottom, the Foix, difference of opinion over this nomenclature, with reference to the different zones referred to as Clark, it has no particular bearing on the water problems. Each of these oil zones has had waters of varying salinity associated with it, either within or at the bottom of the 'zone. Table 1 is a tabulation of the zones, their maximum thicknesses, salinity and heads of various waters. Surface waters are fresh, and of high head, giving artesian flow in some instances.

Jan 1, 1930

For many years it has been known that large bodies of iron ore existed in Iron and Washington counties in Utah. The ore is chiefly hematite-both hard and soft-though some magnetite is found. No definite and complete estimate of the iron ore reserves of the state have been made. The U. S. Geological Survey estimated that 40,000,000 tons of ore were disclosed by development work averaging only 35 feet below the surface of the ore. The ore is found along an area about one and a half miles wide by twenty miles long, and for the most part on the eastern and southern slopes or foothills of Three Peaks. Granite Mountain and Iron Mountain. Later estimates by others have gone as high as ore in sight 164,000,000 tons, probable ore 300,000,000 tons and possible ore 1,000,000,000 tons. Whether this last estimate is too great or not there is sufficient iron ore in Utah to justify the starting of an iron industry. Two companies are now mining iron ore in Utah, the Columbia Steel Corporation and the Utah Iron Corporation. The mine of the Columbia Steel Corporation is at Iron Springs a few miles west of Cedar City. About 650 tons, of ore a day is being shipped to the blast furnace at Ironton. The ore is mined by the glory hole method. After being drilled it is blasted to the bottom of the several glory holes and is dropped through chutes into cars on the ore haulage level below. It is then hauled by electric locomotives to the crushing plant, where it is crushed to blast furnace size before going to storage bins. Some of the softer ore is brought to the chutes by Fresno scrapers.

Jan 1, 1925

By E. T. Turkdogan, L. J. Martonik, R. J. Fruehan

Electrochemical measuretnents of the solid oxide electrolyte galvanic cells CY-Cr2O3 I ZrO2 (CaO) 1 O (in Fe alloy) CY-Cr2O3 I Tho2 (Y2O3)I O en Fe alloy) have been made at 1600°C (2912°F) in order to test the Performance of such cells at liquid steel temperatures. The oxygen pvobe (cell) consists of a disk of ZrO2 (CaO) or Tho2 (Y2O3) electrolyte fused at one end of a silica tube filled with a mixture of Cr-Cr2O3 which is the reference electrode. Upon immersion in liquid steel, the electromotive force readings achieve a steady value within a few seconds, and remain steady for 30 win or more. The perforwzance of the probes has been tested using Fe-O, Fe-Si-O, Fe-Cr-O, Fe-V-O, and Fe-Al-O alloys; the oxygen contents of liquid steel derived from the measured electromotive forces are in satisfactory agreement with those determined by arulysis. Use of the probe in the deoxi-datiorz of steel, in laboratory experiments, is discussed. The results indicate that there is insignificant electronic conductivity in ZrO2(CuO) at oxygen activities down to those corresponding to 10 ppm in steel. At lower oxygen activities, probes tipped with ThOn (Y2O3) disks perform satisfactorily at oxygen activities down to 1 ppm O or less. THE key to the control of deoxidation of steel is a sensing device to measure rapidly the concentration of oxygen in liquid steel in the furnace, ladle or tun-dish at any desired stage of deoxidation. The analysis of the cast steel by the neutron-activation or vacuum-fusion method gives total oxygen as oxide and silicate inclusions. This analysis is important for guidance to steel cleanliness; however, such a postmortem is of little value in the control of deoxidation of liquid steel. At the General Meeting of the American Iron and Steel Institute in New York, 1968, Turkdogan and Fruehan' presented a paper on the preliminary results of the work done in this laboratory on rapid determination of oxygen in steel by an oxygen probe. Details of the work done in this laboratory leading to the development of a galvanic cell for the determination of oxygen in liquid steel, and the results of the tests made are given in this paper. It was through Wagner's contributions, since the early Thirties, to the physical chemistry of semiconductors in general that it ultimately became possible to construct galvanic cells for application at high temperatures. In 1957, Kiukkola and wagner2 successfully demonstrated the use of several solid electrolytes in measuring the free energies of several chemical reactions, in particular, the use of lime-stabilized zir-conia in high-temperature oxidation reactions. Starting 7 years later, a number of papers appeared in the technical literature3-' demonstrating possible applicability of galvanic cells for the determination of oxygen in liquid steel. In the earliest work, Japanese investigators3j4 experimented with various types of reference electrodes, e.g., graphite-saturated liquid iron at 1 atm CO or Ni-NiO mixtures; the results obtained, though promising, were not of sufficient accuracy. Except for the work of Baker and West,6 all other investigators5,7,8 showed that ZrO2(CaO) electrolyte could be used for this purpose. The main part of the galvanic cell used by Fischer and ~ckermann' and by schwerdtfeger7 (the latter work was done in this laboratory), consisted of a ZrO2(CaO) tube, -1 cm ID, closed at one end, with a platinum contact wire fixed mechanically inside the closed end. The tube was flushed with a gas of known oxygen partial pressure, e.g., air, CO-CO2 or H2-CO2 mixtures; gas along with the platinum lead wire served as the reference electrode. The oxygen contents derived from measured electromotive forces agreed reasonably well with the oxygen contents determined by vacuum-fusion analysis. It is evident from recent investigations that the electromotive force technique using a solid oxide electrolyte is fundamentally well suited for the determination of oxygen in liquid steel. However, it is equally clear that the cell arrangement of the type as commonly used is in need of considerable improvement, as it exhibits several shortcomings for industrial and even laboratory use. 1) Because of its size, the zirconia tube, though stabilized, has a poor resistance to thermal shock. 2) Fine pores and microcracks, which are invariably present in zirconia tubes, are detrimental to the satisfactory operation of the cell, particularly when gas reference electrodes are used. 3) Air or carbon dioxide reference electrodes give rise to high electromotive force readings; as a result, the determination of oxygen in steel becomes less accurate. For higher accuracy, the oxygen partial pressure of the reference electrode should be in the range similar to that of oxygen in steel. 4) Even in laboratory experiments, difficulties are experienced when flushing the tube with gases and maintaining the proper gas flow rate. Fischer and Ackermann,' who used air as the reference electrode, reported that when the flow rate was too low, furnace gases would leak into the electrolyte tube, therefore lowering the oxygen potential and measured electromotive force. The required flow rate in order to avoid leakage depended on the tightness of the electrolyte tube which varied with different tubes, thus making it difficult to predict in advance the required flow rate. However, if the flow rate is too high the inside wall of the electrolyte tube would be cooler than the wall

Jan 1, 1970

By Charles N. Bell

The Telluride mining district of southwestern Colorado is defined by the 37" 45' and 38" parallels of latitude and 107" 45' and 108" meridians of longitude. Telluride was never a boom camp, but has had a steady growth. In recent years, notwithstanding the business depression of 1920, the business has been the same as in normal years. The first prospector is said to have appeared in 1875, in which year locations on the Smuggler vein were made. Shipments were made in 1877 and 1878, and in 1879 milling the ores was attempted. While the district produced high-grade ores, it did not become important until 1890, when the Rio Grande Southern R. R. was completed from Ridgway to Telluride. The railroad has since been extended to Durango. In the fall of 1896, 400 stamps were in operation, and the annual production was $3,000,000.00, two-thirds of which was gold. The total production from 1875 to 1923 was: gold $58,274,527; silver 41,-830,920 oz., valued at $31,016,893; copper 15,258,866 lb., valued at $2,533,291; lead 166,056,484 Ib., valued at $8,324,910; zinc 18,141,182 Ib. valued at $1,323,787; or a total production of $101,473,408. All claims are held in fee. Most of them are 1500 by 300 ft. but claims located within the last few years are 1500 by 600 ft. General supplies are obtained at Telluride, Denver, and Salt Lake. The largest mines are within 6 miles of the town of Telluride. Denver is 422 miles and Salt Lake is 439 miles, by rail, from Telluride. One-half of the distance to Denver and one-sixth of the distance from Telluride to Salt Lake is by narrow-gage railroad. The labor is efficient. The best miners are Italians and Austrians, then Slavs, Greeks, and Mexicans follow in the order mentioned. There are no labor unions. There are no serious mine pumping problems, the drainage being through adits. The Tomboy and Smuggler companies pump water from their reservoirs, the former for milling and domestic purposes and the latter for milling, power, and domestic purposes. BIBLIOGRAPHY A partial bibliography of the Telluride District is: Geologic Atlas Telluride No. 57; Preliminary Report on the Mining Industries of the

Jan 1, 1925

By S. Chander, D. W. Fuerstenau

The inherently sluggish nature of the reactions involving sulfide minerals, particularly molybdenite, in aqueous solutions under ambient flotation conditions make their investigation complicated and difficult. Since the physicochemical nature of sulfides is known to be controlled by electrochemical reactions, a number of attempts have been made in the past to study sulfide mineral-collector interactions through rest potential and electrode polarization measurements. The purpose of the present investigation was to study the interaction of potassium diethyldithiophosphate (KDTP) with molybdenite. In the present investigation of the interaction of KDTP at the molydenite surface, molybdenite electrode rest potential measurements and electrode polarization behavior were experimentally determined under various solution conditions. The standard reduction potential for the equilibrium between dithiophosphate ions (DTP-) and bis(diethoxythiophosphoryl)disulfide (DTP) [(DTP). + 2e :i7-± 2DTP- (1)] can be evaluated from the electrode rest potential measurements on a platinum electrode in deoxygenated KDTP solutions saturated with freshly prepared (DTP)2. Experimental A platinum wire was used as the electrode for potential measurements. Prior to each measurement the elec-

Jan 1, 1975

By V. C. Smith

Reliable and detailed statistical data available for Kentucky, Ohio and West Virginia are the most meager and unsatisfactory of any of the producing states. Detailed histories and statistics are available for only a few pools. The antiquity of these pools, loose nomenclature, particularly where several names are applied to the same pool or various parts of the pool or a new namsed when the pool was rediscovered, made the collection of accurat historical and statistical data almost impossible. So many of the data reported are unreliable that a breakdown by pools or even by counties, until more accurate information is available, would lead to gross errors. Rather than perpetuate inaccuracies, we have endeavored to go to original sources wherever possible, sift these and provide data that may serve as an incentive and basis for future work. The necessity for accurate information is thoroughly recognized by the operators, particularly because of the effect of recent government regulations and request? for data in connection with the preparation of the various codes a pending legislation. Producers, both major operating companies and individuals, . freely given their time and assistance in the compilation of these data. Valuable information was obtained from tax records, rate cases, statistics published by the oil and gas publications and the Bureau of Mines. So many individuals cooperated in the preparation of these data that individual credit cannot be given. Undoubtedly many errors will be found. Some of the data are open to controversy, and many have been omitted in the hope that new information of a more reliable character may become available. Other omissions are due to an inability to contact the proper individuals, many of whom are no longer connected with this industry. Pennsylvania grade crude sold in 1933 for the lowest price since 1895. Gas production could not find sufficient new markets to fill the void left by industrial stagnation. In the gas industry, where the market price is fixed by contract, uncertainty persisted because of impending legislative action affecting both taxes and utility rates. As a result of these factors and a lack of new money, drilling was restricted to a new low. The lifting of proration toward the end of the year in the Pennsylvania

Jan 1, 1934

By AIME AIME

ABOUT 55 attended the general session of the Nonferrous Metallurgy Committee on Wednesday afternoon. In opening the proceedings the Chairman, Frank G. Breyer, served notice of his intention to make an early start this year in securing papers for his committee. He voiced the thought that more importance should be attached to the prompt publication of data on new advances in practice; the record of technical progress should be written before the sharpness of the current image becomes blurred by the veil of time. As an illustration, Mr. Breyer declared that great strides have been made in the zinc industry during the past nine years, whereby zinc ore is converted directly to the oxide in large mechanical furnaces, yet the literature is confined to patents.

Jan 1, 1933

By Ronald J. McGregor, Anton R. Hendriksz

INTRODUCTION The NIMCIX contactor was developed in the late sixties at the National Institute for Metallurgy in South Africa, for the main purpose of extracting uraniuy from relatively low-grade uranium solutions. ' The concept was sufficiently developed by 1974 to permit the operation of a 1500 litre per minute column to treat unclarified urgnium-bearing solution under industrial conditions. The plant operated so successfully that several large-scale units have subsequent18 teen constructed and are operating efficiently. ' Total resin consumption figures as210w as 3 per cent per annum have been reported, and the extraction efficiencies of the installations have been exceptionally good. All the solutions treated have been acidic in nature and in every case have been of such a nature as to significantly depress the maximum uranium loading on the resin beads. The chemical constituents of the leach solution fed to the loading column determines the ease with which the soluble uranium can be absorbed by an ion exchange resin. The concentration of competing ions and various resin foulants define the nature of the continuous ion exchange equipment required for efficient extraction performance. The basic NIMCIX concept is retained in these various alternate designs, but batch or continuous elution methods with fully automated or manual control systems may be selected for the different process solution conditions. BRIEF DESCRIPTION OF THE NIMCIX CONTACTOR The NIMCIX ion exchange column is a multi-stage fluidized bed contactor which is designed to permit a counter-current flow of solution and resin in order to maximize extraction efficiency. The flow o resin is periodic, based on the Cloete and Streat 5 principle of reverse flow. The basic operating cycle can be divided into five periods, as illustrated in Figure 1. For the purposes of describing the cycle, the loading column is considered; how- ever, a similar sequence may be applied to the operation of a NIMCIX continuous elution column. S'I'EP 1: During the forward flow period, Solution flows up through the column and fluidizes the resin contained in each stage. The uranium depleted solution overflows the upper flared-section of the column as the tail solution. Step 2: The flow of solution to the column is temporarily stopped and the resin is allowed to Settle onto the plates in the column. STEP 3: During the reverse flow period, a fixed volume of solution is drained from the column to the transfer vessel. This flow causes resin transfer to occur from stage to stage and also out of the bottom stage. At the end of this period, which expires when the low level switch (LS) is actuated, some of the resin is left in the conical section of the column and the pipe interconnecting the column and the vessel. STEP 4: The cone flush period ensures that all the resin left in the cone of the column and the pipe is transferred to the transfer vessel before forward flow commences. STEP 5: The loaded resin in the transfer vessel, which has been isolated from the column, can either be hydraulically transferred to the top of the elution column or eluted in the vessel before being transferred to the top of the loading column. The major advantages associated with the NIMCIX concept are: (i) Simple method of operation (ii) Contactor can readily be scaled up to large diameters. (iii) Because the resin does not pass through pumps or airlifts, and valves cannot be closed on resin beads at any time, the resin losses are exceptionally low. (iv) Operating costs are low. (v) Relatively few valves in the system. (vi) Stable operation is achieved over a wide range of feed rates and concentrations.

Jan 1, 1980

By L. B. Underwood, C. J. Distefano

NORAD, when completed, will be housed in large chambers excavated out of the granite beneath the Cheyenne Mountain near Colorado Springs. A room and pillar layout for the chamber excavation was selected and executed. Many complex problems arose in designing a rock bolt system; this paper includes discussions on: rock strengthening following excavation, excavation and ground support problems, orienting rock bolts with respect to jointing systems, conducting pull tests, four-way chamber intersection problems, the need for grouting rock bolts, and loss of tension and permanency of anchorage in a rock bolt system. In the event of a sudden nuclear attack upon the United States, it is imperative that vital command and control centers have a high probability of survival. One such vital facility is the North American Air Defense Command Combat Operations Center at Colorado Springs, Colo. Known briefly as NORAD, this installation when completed will be housed in large chambers excavated out of granite beneath the eastern slope of Cheyenne Mountain (Fig. 1). The NORAD COC, a U.S. Air Force sponsored project, will serve as the primary collection and evaluation center for data concerning unknown aircraft, missiles, or space vehicles, which might bring destruction to North America. The data will be fed into high-speed computers and electronic equipment from outpost sources: radar, ballistic missile early warning stations and picket ships throughout the world. Electronically controlled display boards will make it possible to evaluate the tracking data instantaneously and to take appropriate defensive action.'

Jan 1, 1968

By AIME AIME

FOLLOWING careful study of the relations of the Institute to students and the younger members of the profession, the Membership Committee recommended to the Board a change of plans abolishing the Junior Associate class of membership, substituting a -Junior membership and providing for Student Associates. The Board adopted this report at its meeting on Nov. 23, and asked Counsel to draft the necessary amendments to the By-laws, and gave formal notice of intentions to amend as provided in Section I, Article XI1 of the existing By-laws. The By-laws as it is proposed to amend Article I, 11, 111, IV, X, and XI follow. The new plan requires no changes in the other Articles. The matter will come before the Board for vote on Jan. 25.

Jan 1, 1929

Experimentation which measures differences in pressure across the interfaces of immiscible fluids in the interstitial spaces of porous media may be termed "capillary pressure experimentation". In the literature of petroleum technology since 1941 there have appeared twelve papers popularizing capillary pressure concepts and developing applications of these concepts for the solution of problems of practical reservoir engineering importance, such as the determination of connate water, fluid distribution. in transition zones, reservoir rock textural properties, and oil recovery from petroleum reservoirs.' Although a review of the literature would be justified at this time in order to reconcile the conflicting viewpoints which are contained in the cited papers, the object of this note will be of more limited scope. It is believed that the recent paper of Muskat alls sufficient attention to many of the uncertainties which arise upon examination of the published literature. such that until satisfactory counter-proposals can be made it will serve our purpose only to mention some other like uncertainties. This will emphasize further the need confronting petroleum technologists to re. consider and reformulate the application possibilities of capillary pressure experimentation. In particular, I sug- gest that we examine the thesis that capillary pressure experimentation as above defined can lead to measurements reflecting the recovery of oil from petroleum reservoirs, as was proposed first" by Amyx and Yuster" and was first reduced to practice by the experimentation of Welge. In fact. I shall deal exclusively with the Welge papers since it is the principle one on this subject which has appeared to date. I shall attempt to show that the possibility of describing oil recovery features in terms of capillary pressure phenomena has not been established entirely. The Welge paper was a pioneering effort to evaluate this recovery application possibility. P. P. Reichertz' comments on the Welge paper state that non-wetting phase discontinuities are developed occasionally in the Welge experiment, and restate Muskat's argument that discontinuous fluid elements (partially saturating the interstices of porous media which are elsewhere saturated with some other immiscible phase or phases) are not subject to the requirements of hydrostatic equilibrium. It is the purpose of my comment to show that it is unnecessary to make Reichertz' postulation regarding non-wetting phase discontinuities (however valid) when it is desired to criticize welge's theoretical treatment of his problem. It can be shown that Welge's method of measuring values for ''capillary pressure" is invalid in many instances of application, such that his reported curves of capillary pressure Versus fluid saturation often have no physical meaning, even throughout the interval of fluid saturation where it might be otherwise suspected that no phase discontinuities occur. By considering established principles of capillary pressure experimentation it can be shown that the pressure difference experimentally observed between wetting and non-wetting fluid Phases which are contained in external reservoirs will reflect on the capillary pressure difference at the interfaces of contact between these phases only when the following conditions are satisfied: (a) There shall be a balance between the opposing forces of gravity and capillarity, as obtains under conditions of hydrostatic equilibrium when the positions of the interfaces of contact become fixed in pore spaces of certain geometry (b) The wetting and non-wetting fluids within the interstitial spaces shall everywhere be continuous with the external wetting phase reservoir and the external non-wetting phase reservoir, respectively. It will become apparent immediately that in any instance when a greater pressure is recorded in the external wetting phase reservoir than in the external non-wetting phase reservoir, one may establish either that static equilibrium has not been attained or that discontinuities in one or more of the fluids have been developed. This is because the pressure otherwiee is always ereatest in the non-wetting phase at each static interstitial interface of contact with the wetting phase. such that the externally measured pressure in the non-wetting phase likewise must be greatest if the above conditions are to be satisfied.

Jan 1, 1949

Experimentation which measures differences in pressure across the interfaces of immiscible fluids in the interstitial spaces of porous media may be termed "capillary pressure experimentation". In the literature of petroleum technology since 1941 there have appeared twelve papers popularizing capillary pressure concepts and developing applications of these concepts for the solution of problems of practical reservoir engineering importance, such as the determination of connate water, fluid distribution. in transition zones, reservoir rock textural properties, and oil recovery from petroleum reservoirs.' Although a review of the literature would be justified at this time in order to reconcile the conflicting viewpoints which are contained in the cited papers, the object of this note will be of more limited scope. It is believed that the recent paper of Muskat alls sufficient attention to many of the uncertainties which arise upon examination of the published literature. such that until satisfactory counter-proposals can be made it will serve our purpose only to mention some other like uncertainties. This will emphasize further the need confronting petroleum technologists to re. consider and reformulate the application possibilities of capillary pressure experimentation. In particular, I sug- gest that we examine the thesis that capillary pressure experimentation as above defined can lead to measurements reflecting the recovery of oil from petroleum reservoirs, as was proposed first" by Amyx and Yuster" and was first reduced to practice by the experimentation of Welge. In fact. I shall deal exclusively with the Welge papers since it is the principle one on this subject which has appeared to date. I shall attempt to show that the possibility of describing oil recovery features in terms of capillary pressure phenomena has not been established entirely. The Welge paper was a pioneering effort to evaluate this recovery application possibility. P. P. Reichertz' comments on the Welge paper state that non-wetting phase discontinuities are developed occasionally in the Welge experiment, and restate Muskat's argument that discontinuous fluid elements (partially saturating the interstices of porous media which are elsewhere saturated with some other immiscible phase or phases) are not subject to the requirements of hydrostatic equilibrium. It is the purpose of my comment to show that it is unnecessary to make Reichertz' postulation regarding non-wetting phase discontinuities (however valid) when it is desired to criticize welge's theoretical treatment of his problem. It can be shown that Welge's method of measuring values for ''capillary pressure" is invalid in many instances of application, such that his reported curves of capillary pressure Versus fluid saturation often have no physical meaning, even throughout the interval of fluid saturation where it might be otherwise suspected that no phase discontinuities occur. By considering established principles of capillary pressure experimentation it can be shown that the pressure difference experimentally observed between wetting and non-wetting fluid Phases which are contained in external reservoirs will reflect on the capillary pressure difference at the interfaces of contact between these phases only when the following conditions are satisfied: (a) There shall be a balance between the opposing forces of gravity and capillarity, as obtains under conditions of hydrostatic equilibrium when the positions of the interfaces of contact become fixed in pore spaces of certain geometry (b) The wetting and non-wetting fluids within the interstitial spaces shall everywhere be continuous with the external wetting phase reservoir and the external non-wetting phase reservoir, respectively. It will become apparent immediately that in any instance when a greater pressure is recorded in the external wetting phase reservoir than in the external non-wetting phase reservoir, one may establish either that static equilibrium has not been attained or that discontinuities in one or more of the fluids have been developed. This is because the pressure otherwiee is always ereatest in the non-wetting phase at each static interstitial interface of contact with the wetting phase. such that the externally measured pressure in the non-wetting phase likewise must be greatest if the above conditions are to be satisfied.

Jan 1, 1949

By P. Greenfield, C. C. Smith, A. M. Taylor

The Mg-Zr alloy ZA and Mg-Mn alloy AM503(S) are shown to have a markedly improved resistance to creep deformation after suitable heat treatments. This improvement makes them suitable for certain stress-bearing fuel element components in nuclear reactors. The extent of strengthening is described and an explanation of the behavior of both materials is given, based on a combination of strain-aging and grain growth. The increase in operating temperatures of fuel element components in Calder Hall type nuclear reactors has necessitated the development of magnesium base alloys with a very high resistance to creep at temperatures up to 500°C. Such alloys are not required for fuel element cans, which require high-creep ductility rather than strength, but for can supporting and stabilizing components, which are needed to support the imposed loads without deforming more than about 1 pct in times of up to 40,000 hr. The amount and type of alloying addition made to magnesium for these parts is limited by the necessity of keeping the cross-section to thermal neutrons as low as possible. The alloys must also possess a high resistance to oxidation in CO2. Alloys which have been developed for this application include ZA, an alloy of magnesium with 0.5 to 0.7 pct Zr and AM503(S), an alloy of magnesium with 0.5 to 0.75 pct Mn. In the as-extruded condition these alloys are very weak and ductile in creep but it has been found that they can be strengthened to a significant extent by heat treatment. This paper describes the method of developing a high-creep resistance in ZA and AM503(S), the extent of the strengthening produced and discusses the probable mechanisms of strengthening. TEST MATERIALS Specimens were taken from typical casts of ZA and AM503(S) alloys extruded into 2 1/4-in.-diam bars, supplied by Magnesium Elektron Ltd. Typical analyses of the bars were as follows: The as-extruded mean grain diameter was 0.001 to 0.002 in. for the ZA alloy and 0.003 in. for the AM503(S) alloy. EXPERIMENTAL METHODS Extruded bars of ZA alloy, 2 1/4 in. in diameter and 9 in. long, were heat treated in electrical resistance furnaces in an atmosphere of flowing CO2 containing 50 to 300 ppm water, thereby reducing the extent of oxidation compared with that which would have occurred in air. Heat treatments were carried out at 600oc for times of 8, 24, 48, 72, and 96 hr and material was subsequently both furnace cooled and water quenched. In order to measure the effect of time of heat treatment, specimens were creep tested at 400°C and 336 psi for about 1000 hr. Subsequently, the behavior of material heat treated for 96 hr at 600°C and furnace cooled was tested at a variety of stresses from 200° to 500°C. Tests were also conducted at 200o and 400°C on material in the as-extruded condition for comparative purposes. With the AM503(S) alloy, only the effect of heat treatment at 565°C for 4 hr was examined. It has been shown1 that such a heat treatment produces marked strengthening in this alloy. Tests on this material were conducted at a variety of stresses at 200°, 300°, and 400oc with comparative tests on as-extruded material at 200o and 400°C. The creep tests were carried out on machines using dead-weight loading and direct micrometer strain measurements on specimens 5 in. long and 0.357 in. diameter. At temperatures of 400° C and below, the creep tests were conducted in air, but at higher temperatures an atmosphere of CO2 was used. Grain size measurements were made on ZA in the extruded and heat treated states and on each specimen after creep testing. This was done by a line count of a minimum of 20 grains in two or three random fields in the longitudinal and transverse directions. The same method was used for measuring the grain size of as-extruded AM503(S), but the grain size of the heat treated material was so large that this method could not be employed. For heat-treated AM503(S) the large grained characteristics (between 0.1 and 1 in.) were confirmed by the measurement of individual grains. In the case of the ZA alloy, specimens taken from various stages in the program were analysed for hydrogen by a combustion method. Material in various states was also analysed for the soluble and insoluble zirconium content by dissolving in dilute hydrochloric acid. This technique has been useda for the determination of amounts of zirconium present

Jan 1, 1962

G. R. GOHN. l-1n Table I11 of The Sager, Brown, and Mears paper, which was presented on the screen, data were given showing the results of accelerated corrosion tests of certain magnesium alloys. Mention was made that these were carried to a certain time which was used as a measure of failure but no mention was made as to the period of time. I would like enlightenment on that. G. F. SAGER (Author).-In reply to Mr. Gohn's question regarding the times of exposure for the accelerated stress-corrosion tests referred to in Table I11 of our paper, which shows the correlation between accelerated and atmospheric stress-corrosion tests on magnesium alloys, I can say that we usually run the accelerated tests on such alloys for at least 500 hr. We feel that this is long enough to reveal any marked susceptibility to stress-corrosion cracking. In the case of the atmospheric tests on such alloys, we have not yet decided how long we should expose the specimens. Most of them are being exposed for indefinite periods and a good many of our specimens have now been exposed for several years. We may want to continue some of the tests for five or ten years. The period of six months mentioned in connection with the times of exposure for the atmospheric specimens was a rather arbitrarily selected minimum time for which specimens had to be exposed before we counted them with those that had not failed. A fairly large number of magnesium- alloy specimens have been exposed in the atmospheric stress-corrosion tests at var-

Jan 1, 1945