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By George Smith

TWELVE years ago, the Director of the United States Geological Survey addressed to the Secretary of the Interior a letter calling attention to the government's need for liquid fuel for naval use and pointing out that the rate of increase in demand was more rapid than the increase in production.1 This letter, in a way, inaugurated the policy of public oil-land withdrawals, which was well founded in its primary purpose of protecting the oil industry and highly desirable in its immediate effect of checking the over-development of that day in California. Unfortunately, however, through delays in legislation, this policy may be regarded now as having outlived both its intent and its usefulness. In 1908, the country's production of oil was 178,500,000 bbl., and there was a surplus above consumption of more than 20,000,000 bbl. available to go into storage.: In 1918, 10 years later, the oil wells of the United States yielded 356,000,000 bbl.-nearly twice the yield of 1908-but to meet the demands of the increased consumption more than 24,000,000 bbl. had to be drawn from storage. Nor is this all of the brief comparison. In 1918, our excess of imports over exports of crude petroleum was nearly 33,000,000 bbl. whereas in 1908 we exported 3,500,000 bbl., which was net, as we had not begun to import Mexican oil. In this period, the annual fuel-oil consumption of the railroads alone has increased from 16,871,000 to 36,714,000. bbl.; the annual gasoline production from 540,000,000 gal. to 3,500,000,000 gal. This record may be taken not only as justifying the earlier appeal for Federal action, but as warranting deliberate attention to the oil problem of today.

Jan 1, 1920

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 C. H. McGuirk

Although preventive maintenance is not a new concept and has many proven applications, it is believed that the Pittsburgh & Conneaut Dock Co.'s Computerized Preventive Maintenance System is the first and possibly the only application related to heavy duty bulk material handling equipment. This paper is presented to describe the development, installation, and application of a Computerized Preventive Maintenance System applied to an 18 million t (20 million st) coal and iron storage and reclaim facility located on the shores of Lake Erie at Conneaut, Ohio.

Jan 1, 1978

By William Kent

During the discussions at the Philadelphia meeting in February last;) several speakers expressed their doubts of the general accuracy of chemical analyses of steel made by "iron works chemists," and especially of determinations of manganese. Since the meeting, the discussion of the " practical value of chemical analyses" has been continued at some length in 'the columns of the Iron Age.

Jan 1, 1882

By S.G. Bankoff

Ince1 proposed that electrostatic attraction between oppositely charged particles was responsible for slime-coating. Del Giudice2 postulated the metathetic formation of a cementing compound. Wark3 suggested that prevention of slime-coating was related to peptization of the slime. In the experiments of Table I the technique employed was essentially that of del Giudice, with the difference that the particle was examined under a film of water rather than dry.4 In general, the polished particle was agitated for 2 min. in a pulp consisting of 12.5 grams of the slime (—200 mesh) and 50 C.C. of distilled water, washed in three baths of distilled water, and examined at 220 diameters with the Leitz Ultropak. Observations of Brownian movement were made at 850 diameters with dark-field illumination. Several of these experiments do not jibe with the metathesis theory. According to published solubilities,5,6 the lead salts of the anions in experiments c through g are more insoluble than lead carbonate, there- fore should prevent the formation of lead carbonate on the galena surface. In experiment i the calcium oxalate, which precumably was on the calcite surfaces, should have permitted the formation of a lead carbonate cement by virtue of its greater solubility. Experiments j through m show that the addition of lime accelerates the deposition of quartz onto a galena surface. The writer is unable to postulate a satisfactory cementing compound, according to the metathesis theory, to explain this effect. These experiments led to the conclusion that the metathetic formation of a cement-

Jan 1, 1943

By S. G. Bankoff

Ince1 proposed that electrostatic attraction between oppositely charged particles was responsible for slime-coating. Del Giudice2 postulated the metathetic formation of a cementing compound. Wark3 suggested that prevention of slime-coating was related to peptization of the slime. In the experiments of Table I the technique employed was essentially that of del Giudice, with the difference that the particle was examined under a film of water rather than dry.4 In general, the polished particle was agitated for 2 min. in a pulp consisting of 12.5 grams of the slime (—200 mesh) and 50 C.C. of distilled water, washed in three baths of distilled water, and examined at 220 diameters with the Leitz Ultropak. Observations of Brownian movement were made at 850 diameters with dark-field illumination. Several of these experiments do not jibe with the metathesis theory. According to published solubilities,5,6 the lead salts of the anions in experiments c through g are more insoluble than lead carbonate, there- fore should prevent the formation of lead carbonate on the galena surface. In experiment i the calcium oxalate, which precumably was on the calcite surfaces, should have permitted the formation of a lead carbonate cement by virtue of its greater solubility. Experiments j through m show that the addition of lime accelerates the deposition of quartz onto a galena surface. The writer is unable to postulate a satisfactory cementing compound, according to the metathesis theory, to explain this effect. These experiments led to the conclusion that the metathetic formation of a cement-

Jan 1, 1943

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's' 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 Frank Robertson Van Horn

In June, 1911, the writer spent a few days in studying the economic geology of the vicinity of Park City. During this rather hurried visit a number of specimens of ore were collected, which have since been examind. The results of these investigations show that bournonite (PbCu-SbSa) is present in the ores in greater or less quantity. This fact has never before been reported, as far as can be learned. The failure to recognize this mineral is due to its similarity to tetrahedrite, with which it has probably been confused during a long period of years. Jamesonite (Pb2sb2s6) has been reported from the region in a rather doubtful manner, but the writer has seen it in notable amounts from several mines, and can offer the first analysis of this mineral from the district. Calamine (HzZn2SiO5) was found at one mine and has never been ecognized and reported from the district. Geogbaphy and Geology Park City, Utah, is located at an elevation of about 7,000 ft. above sea level on the eastern slope of the Wasatch mountains. It is situated approximately 25 miles southeast of Salt Lake City. ' The geology and ore deposits have been described in detail by Bout well and Woolsey.' The mines visited are situated south-southeast from the town. The Silver King Coalition mine is located in Woodside gulch about 1 mile southeast of Park City, at an altitude of about 8,100 ft. The other mines visited were the Daly West and Quincy, which are in Empire canyon about 2 miles sontheast of the town, at elevations of 8,300 to 8,500 ft. respectively. The Daly Judge tunnel goes into the mountain from Empire canyon about 1 mile south of the city, at an altitude of 7,700ft.

Jan 1, 1915

By Reynold Q. Shotts

Chemical methods, based on the relative rates of oxidation of fusain, bright coal, and dull coal by nitric acid, have been devised to determine these coal components.1-4 Results obtained by oxidation methods for fusain have been checked against results obtained from microscopic methods on duplicate samples of the same coals, but to the author's knowledge this has not been done for bright and dull coal components. For this reason it is not certain that the two methods of analysis identify essentially the same chemical or physical units. It would be highly desirable to see results of the application of both methods to duplicate samples, but in the absence of any such data the author has attacked the problem indirectly. From the U. S. Bureau of Mines samples were obtained of three Alabama coals which the USBM had analyzed optically and reported on over the past 30 years. These samples were subjected to analyses by oxidation rate methods. Results of this work, and comparisons with the USBM analyses, have been published. This was the first indirect approach to the problem. The present report attempts a second indirect approach by way of internal validation.

Jun 1, 1955

By V. F. Swanson

A petrographic study was made of the type and sources of mineral contamination occurring in Florida phosphate rock products. Emphasis was placed on contaminants in the screened rock (+1 mm), since this portion of the product undergoes no physical beneficiation except for scrubbing to remove slimes. Since iron and aluminum contents of the finished product affect the salability, special emphasis was placed on identifying types and sources of these contaminants and relating chemical composition to visual characteristics. Wavellite derived from the overburden was the major aluminum contaminant with some aluminum being included as secondary clay balls. Iron occurred as phosphates in the overburden and as colloidal oxides included in the phosphate pebbles. Chert and limestone contamination derived from the Hawthorne formation underlying the phosphate matrix.

Jan 1, 1972

By Henry Howe

§1. FOUR ASPECTS OF FLOW in the plastic deformation of steel by overstrain, such as punching, wire-drawing, tensile rupture, etc., are: (1) The inter-granular, i.e., the relative movements of the several grains, each as a whole; (2) the intra-granular, i.e., the relative movements of the masses of ferrite or cementite and pearlite within those grains; (3) the intra-pearlitic, i.e., the relative movements of the pearlitic ferrite and cementite; and (4) the crystal unit slipping, i.e., the travel of the minute units past each other, along the slipping planes, giving rise to the slip bands of Ewing and Rosenhain. It may be objected justly that (2), (3), and (4) are in a sense "intra-granular," and that (4) is in a sense "intra-pearlitic." Hence clearness may be gained at times by calling these "Movements of the 2d, 3d, and 4th orders" respectively.

Jan 4, 1914

By Robert E. Tally

Underground fires have been common in the mines of the United Verde Copper Co. for the past 22 years. The first fire started in the 300 Hampton stope in the fall of 1894, following a cave in that orebody. The soft and highly pyritic nature of the ores is responsible for most of these fires. Since ore characteristics, methods of mining and ventilation, have an important influence on mine fires, they will be described in this paper. Orebodies The ores are mostly chalcopyrite except on the upper levels where considerable chalcocite, black oxides and other secondary minerals occur. The orebodies are in the form of lenses and vary in size. Some are small, while others are several hundred feet in length by a hundred or more feet in width. These orebodies extend, in some cases, from the surface to the lowest levels of the mine and usually at a steep angle of inclination. There are three different classes of ores, classified in accordance with the gangue rock. The copper in all cases, except as above specified, is in the form of chalcopyrite. The largest and most important of these reserves are in a pyrite gangue. Next in order of importance are the schist ores and lastly the quartz porphyries. The pyrite, locally termed iron ores, average from 30 to 42 per cent. sulphur. The schist and quartz porphyries vary from 3 to 25 per cent. sulphur. Mining Methods All the orebodies were worked by the overhand square-set method of mining prior to 1908; since then the cut-and-fill, shrinkage and mill-hole systems have been largely employed. But 15 per cent. of the total tonnage now extracted is from timbered stopes. Most of this is from the upper levels where the ore is soft, heavy and more or less broken to the surface. Large reserves of these ores are being conserved for more efficient methods of mining.

Jan 1, 1917

By Y. Baskin

Solid-solubility relationships in the Pseudobinary systems UAS-UP, UAs-US. UAS-UC, aid UAs-UN were investigated. The first two systems exhibit complete mutual solubility, whereas the component compounds in the other two systenzs are immiscible. The above information, together with solid-solubility data joy six additional pseudobinary systems , were analyzed for compliance wilh the Hurrze-Rothery rules for rnetallic systems. The relative size difference of the component nonmetal atoms was found to be the dopainant jactor determining the extent of solid solubility between the NaC1-type uranium compounds. The anionic and covalent radii of the nonmetal atoms appear to be inadequate for these systems, but compuled radii based on rare earth compounds yield consistent results for the uranium compounds. THE actinide elements, like metallic elements of the transition and rare earth series, readily form binary compounds with nonmetallic elements of groups IV, V, and VI of the periodic table. Of particular importance are the NaC1-type equiatomic compounds with carbon, nitrogen, sulfur, phosphorus, and arsenic. The uranium members of this family of compounds have high melting points, are essentially stoichiometric, and exhibit various amounts of mutual solubility. Thus, they are of interest for investigating the factors governing the extent of solid solubility. Previous investigators have determined the solid-solubility limits in the pseudobinary systems between the compounds UC, UN, US, and UP. Anselin et a1 .' reported complete miscibility in the system UC-UN. Baskin and shalek 2 and Allbutt et a1.3 reported that UP and US exhibit complete mutual solubility. Shalek and white4 reported partial miscibility in the system US-UC. At 1800°C the maximum solubility of UC in US is 40 mol pct, but that of US in UC is 4 rnol pct. shalek5 found limited solubility in the system US-UN; the maximum solubility of UN in US is 11 rnol pct at 1800°C, while that of US in UN is only 0.3 mol pct. White and askin 6 found very limited miscibility in the system UP-UC at 1800°C. Approximately 7 mol pct UC is soluble in UP, but there is no solubility of UP in the monocarbide. Phase relations in the pseudo-binary system UN-UP were investigated by askin.' Approximately 0.7 mol pct UN is soluble in UP at 1800°C, while UP is immiscible in UN. The present study was carried out to explore the extent of terminal solubility in the systems UAs-UC, UAs-UN, UAs-US, and UAs-UP. This information, combined with existing data, provided a sufficient basis on which to determine the factors governing solid solubility in pseudobinary systems containing NaC1-type uranium conpounds. I) EXPERIMENTAL 1) Materials. The compounds UC and UN were obtained from the Kerr-McGee Corp. and United Nuclear Co., respectively. The US, UP, and UAs were synthesized by reacting finely divided uranium with H2 S, pH3, or AsH3 gas at low temperature (300° to 500°C), followed by homogenization in a vacuum at moderately high temperatures (1400° to 1700°c).8-10 The materials were essentially stoichiometric, with the exception of UC, which exhibited a C/U ratio of 1.05. Oxygen was the major contaminant in these compounds, ranging from 0.05 wt pct in US to 0.30 wt pct in UC, and it was generally combined with uranium to form UO2. The UO2 content in these materials was usually of the order of 1 wt pct, and did not exceed 2 wt pct. Furthermore, no evidence was found for a high-temperature reaction between uranium dioxide and any of the compounds. Chemical analyses of equilibrated compositions in the systems UAs-UP and UAs-US showed that the non-metal atom to uranium ratios averaged about 1.01, and that the oxygen contents ranged from 0.06 to 0.22 pct. However, the small deviations from stoichiome-try or the presence of minor oxygen impurities do not invalidate the conclusions to be drawn from this study. 2) Experimental Procedures. The component compounds in powdered from were blended in the desired proportions for 5 hr in the ball mill that consisted of stainless-steel balls in a plastic container. Chemical analyses indicated very little metallic pickup from the blending operation and virtually no increase in oxygen content. The pellets were pressed in a 0.270-in.-diam steel die under 40,000 psi pressure. One wt pct of stearic acid dissolved in CCl 4 served both as a binder and as a die lubricant. Chemical analyses revealed that the stearic acid left no carbon residue in the sintered samples. The pellets were sintered in vacuum in an unsealed tantalum crucible. The temperature, measured with a calibrated optical pyrometer, was maintained at 1800" + 30°C for 3 hr. This was sufficient time for attaining equilibrium as no change occurred in either the lattice parameters or the sharpness of the X-ray patterns when samples were annealed for longer periods of time. The pellets were cooled with the furnace. Debye-Scherrer powder patterns were taken at room temperature with a 114.59-mm-diam Norelco powder camera and CuKor radiation (CuGI = 1.5405A). Unit cell dimensions were determined from a Nelson-Riley extrapolation to the high-angle reflections. The values for were precise to k 0.001A. 11) RESULTS X-ray and met allographic investigation revealed that complete mutual solid solubility exists in the pseudobinary systems UAs-UP and UAs-US. The lattice parameter vs composition plots, Fig. 1, show a

Jan 1, 1968

By J. Szekely

A rrlethod is presented for the estitnation of oxygen pickup by teettzed molten steel streams. Of the mechanisrt~s considered for oxygen absorption, physical entrainment appeared to be the most significant. The estent of this physical entrainment may be calculated by the application of boundary layer theory. It was found that the values of oxygen pickup thus predicted were in wry good agreement with data reported in the literature, in the case of short, well-defined metal streams. This entrainment model does not provide an adequate description of oxygen pickup by long streams, exoosed to external winds and where breakup of the streatn is likely. WheN molten steel is teemed into a mold or tundish it will absorb oxygen contained in its environment. Recently interest has been expressed in the measurement and possible prediction of the extent of this oxygen absorption: this interest owes its existence to two principal factors: a) the desirability of providing a quantitative assessment of the role played by the absorbed oxygen in impairing the quality of (vacuum degassed. stainless, or continuously cast) steel; b) the need for providing guidelines for stream protection methods. The purpose of this communication is to suggest a simple method for the prediction of oxygen absorption by continuous metal streams and to compare the predicted values with the data available in the literature. It is hoped that this method may provide at least an initial framework for the interpretation of additional data that might become available. FORMULATION Consider a continuous metal stream falling into a molten metal pool as depicted in Fig. 1. This system may absorb oxygen due to the following two mechanisms: 1) physical entrainment of gases (including oxygen) into the molten pool where reactions. thus absorption, will occur; 2) mass transfer (convec:tive diffusion) of oxygen to the metal stream. 1) Physical Entrainment. The physical entrainment may be calculated by using the concept of the diaplace-ttzent tlzickness of the laminar boundary layer, which will be stated briefly in the following.&apos; When a fluid flows past a solid surface, a portion of the fluid close to the surface is retarded due to fric-tional forces. This region in which the velocity of the fluid differs from that in the main stream is called the boundary layer. An illustration of this is given in Fig. 2 where it is seen that the thickness of the boundary layer increases as we move along in the x direction. In the laminar region, when Re, < 10&apos; the thickness of the boundary layer is given by the following relationship: f =4.64 Re;1" [1] where 61 is the boundary layer thickness, x is the length along the leading edge, Us is the velocity of the free stream, (i is the viscosity of the fluid (gas in this instance).

Jan 1, 1970

By Walter S. Larsh

The Ruth orebody, so far developed, is roughly oval in plan, major and minor axes about 1600 ft. (457 m.) and 1200 ft. (365 m.) respectively, average thickness about 120 ft. (36 m.), and with a general dip of about 15" to the northwest. According to the generally accepted theory, the ore is a secondary enrichment of the porphyry due to leaching in situ by meteoric waters. Copper occurs as chalcocite, chalcocite coating pyrite, and a little chalcopyrite. The leached zone, or capping, covering the ore varies in thickness from 110 to 540 ft. (33 to 164 m.), average about 410 ft. (124 m.). The ore is blue gray in color, and the capping, light yellow to brown. Ore was first discovered in quantity in the workings from the Ruth shaft, now caved. Further development work was done by churn drills, and the outline of the orebody, as stated above, determined in this manner. Drilling is still being carried on. The porphyry area is entirely surrounded by sedimentaries, limestones, and shales; and, in so far as the underground workings have shown, the porphyry itself, the sedimentaries&apos; near the contact, and the country underlying the ore (igneous or sedimentary) is very soft, heavy, and in places swelling ground. All openings have to be carefully and stoutly timbered, and, after once driven, they have to be constantly eased off and repaired. The mine Is at present served by two shafts, the Star Pointer, the main working shaft, a vertical, and the Ingersoll, an incline used for waste and material. The two shafts are about 2600 ft. (792 m.) apart, connected on the 500 level; a connection is now being driven on the 600 level. (Dec., 1917. This connection is now completed.) The 300 level, which is finished, and the 400 level which is nearly completed, are accessible only from the Ingersoll and connections with the 500 level. The 300 level was developed for and mined by the shrinkage stope system, similar to that used successfully in the Ray Consolidated property.

Jan 1, 1918

By Lawson P. Entwistle

SUMMARY ONE of the important reserves of manganiferous iron ore is at Boston Hill, near Silver City, New Mexico. The area consists of a faulted block of gently dipping Lower Paleozoic shale, dolomite, limestone and sandstone, which have been intruded by a roughly circular mass of quartz-bearing monzonite porphyry and subordinate dikes. From a noselike protuberance of the intrusion radiate many premineral faults, which have localized much of the hypogene mineralization. Three important stages of hypogene mineralization can be recognized: (1) mesitite, a manganiferous iron magnesite, (2) quartz sulphides, and (3) barite-galena. The carbonate stage is widespread but stronger near the intrusion. The quartz may have been derived from hydrothermal alteration of the igneous rocks. Barite-galena is most important in the Chloride Flat mining district, about one mile north, where argentiferous galena provided silver for the supergene ore. The hypogene carbonate, lean in iron and manganese, has been oxidized and consequently enriched by meteoric waters containing an excess of oxygen and carbon dioxide to form ore bodies of intimately mixed hematite and pyrolusite. The ore bodies, at one place attaining a length of 1600 ft., a width of 300 ft., and a thickness of 25 ft., are largely confined to areas of brecciation and to spreads from faults in Silurian dolomite beneath soft Devonian shale.

Jan 1, 1944

On the following pages are abstracts of papers published by the Institute during the year 1934 as TECHNICAL PWLICATIONB, CONTRIBUTIONS, m bound volumes and in MINING AND METALLURGY. For abstracts of papers that appear In bound volumes in 1934 but that were published as TECHNICAL PWLICATIONS m 1932 or 1933, see the TRANSACTIONS for 1932 and the YEAR BOOK dated January, 1934. Many of the TECHNICAL PWLICATIONS have been reprinted In bound volumes Information regarding this disposition, and number of pages in each paper, may be found m the list beginning on page 92 Volume numbers are given as listed at the beginning of the index, page 99 The abstracts are grouped as follows:

Jan 1, 1935

By W. E. Bergman, P. G. Carpenter, H. B. Fisher

The conditions under which barium carbonate can be used to remove sulfates from drilling muds are limited The amount of sulfate remaining in solution in the system after treatment with barium carbonate is shown to be a function of the concentration of the carbonate and barium ions and the concentration of other electrolytes. Barium hydroxide may advantageously replace barium carbonate when the contamination is not entirely due to anhydrite (calcium in the system is then stoichiometrically less than sulfate) or when the carbonate concentration is high. The effect of substances such as quebracho, phosphates, and chromates, which form complexes or precipitates with barium, is discussed. INTRODUCTION As the complexity of the operations in drilling for oil has increased, more attention has of necessity been directed to the problems pertaining to the maintenance of good drilling mud properties. As a result, chemical treatment of muds has become an important factor in recent years. Some of these treatments have been designed to eliminate the deleterious effects of contaminants in aqueous mud systems by precipitation or other means. The most common of substances encountered during drilling include sodium chloride, cement, and calcium sulfate while various other contaminants: usually in small amounts, may be introduced from the water, clays, and other materials used in preparation of the mud. In certain cases, for example where continued salt-water flow is encountered or massive anhydrite is drilled, special muds may be used so that the physical properties of the mud will remain satisfactory for drilling. In other cases, it is desirable to remove the contaminants so that soluble electrolytes in the system are maintained at low values. For sulfate contamination, the conlmon practice in the field is to add barium carbonate to precipitate the sulfate as barium sulfate Ordinarily such a procedure gives satisfactory results. There have been important instances, however, where addition of barium carbonate was not effective in removal of soluble sulfates from drilling muds. and it is to these cases that the present paper is directed. While it is generally known that barium carbonate is not always effective in removing soluble sulfates from drilling muds, certain inconsistencies appear in the literature as to the limitations of its use, and little explanation for the limitations are given. Varnell and Kimbrel state that "the treatment (with barium carbonate for removal of sulfate) is simple and consists in maintaining a pH of 9 with caustic soda and quebracho." They caution that concentrations of quebracho greater than 1 lb./bbl. may inhibit the reaction. In another publication&apos;, a pH of 10.5 is considered "the maximum desirable," and the indication is that as much as 2.5 lb. quebracho per barrel may be present in the particular mud under discussion. Lancaster and Mitchell5 state that appreciable amounts of phosphates in the mud will inhibit the reaction with barium carbonate and that the phosphate treatment should be discontinued at least 24 hours before addition of the carbonate. Experimental work was initiated to ascertain the factors involved in using barium carbonate for the removal of sulfate contamination in drilling muds. While the experimental data herein reported are limited, they focus attention on the pertinent factors which must be considered for successful treatment. These factors are discussed from a practical and a theoretical view, the latter being supported by equilibrium data found in the literature. Further, it will be appreciated that the factors involved in this specific study will be closely analogous to those in certain of the other chemical treatments which involve a precipitation of the soluble contaminant. A thorough comprehension of these factors should result in a more fruitful application of this type of chemical reaction to the treatment of drilling muds. EXPERIMENTAL A. Reagents Two muds were used during this investigation. For one series of tests, bentonite suspensions were prepared by dilution of a stock suspension containing 8 per cent by weight of bentonite (Aquagel). For another series, a 6.4 per cent ben-tonitic mud weighted to 9.7 lb./gal. with barium sulfate (Mag-cobar) was used. Distilled water was used in all preparations. The quebracho (72% tannin extract) was obtained from the Thompson-Hayward Co. of Tulsa and contained 11.4 per cent moisture (105 C.). All other materials were reagent grade, and concentrations were corrected for water of crystallization, if any. All concentrations are expressed in pounds per barrel (42 gallons). B. Technique The systems — either mud or water — were contaminated with either sodium or calcium sulfate after treatment with the desired amounts of sodium hydroxide and quebracbo. For treatments with barium carbonate an approximately 3-fold excess (5 lb./bbl.) was used over that computed to be required to precipitate all the sulfate as barium sulfate. Barium hydroxide was used in concentrations of 2 lb./bbl. — about

Jan 1, 1949

By P. G. Carpenter, H. B. Fisher, W. E. Bergman

The conditions under which barium carbonate can be used to remove sulfates from drilling muds are limited The amount of sulfate remaining in solution in the system after treatment with barium carbonate is shown to be a function of the concentration of the carbonate and barium ions and the concentration of other electrolytes. Barium hydroxide may advantageously replace barium carbonate when the contamination is not entirely due to anhydrite (calcium in the system is then stoichiometrically less than sulfate) or when the carbonate concentration is high. The effect of substances such as quebracho, phosphates, and chromates, which form complexes or precipitates with barium, is discussed. INTRODUCTION As the complexity of the operations in drilling for oil has increased, more attention has of necessity been directed to the problems pertaining to the maintenance of good drilling mud properties. As a result, chemical treatment of muds has become an important factor in recent years. Some of these treatments have been designed to eliminate the deleterious effects of contaminants in aqueous mud systems by precipitation or other means. The most common of substances encountered during drilling include sodium chloride, cement, and calcium sulfate while various other contaminants: usually in small amounts, may be introduced from the water, clays, and other materials used in preparation of the mud. In certain cases, for example where continued salt-water flow is encountered or massive anhydrite is drilled, special muds may be used so that the physical properties of the mud will remain satisfactory for drilling. In other cases, it is desirable to remove the contaminants so that soluble electrolytes in the system are maintained at low values. For sulfate contamination, the conlmon practice in the field is to add barium carbonate to precipitate the sulfate as barium sulfate Ordinarily such a procedure gives satisfactory results. There have been important instances, however, where addition of barium carbonate was not effective in removal of soluble sulfates from drilling muds. and it is to these cases that the present paper is directed. While it is generally known that barium carbonate is not always effective in removing soluble sulfates from drilling muds, certain inconsistencies appear in the literature as to the limitations of its use, and little explanation for the limitations are given. Varnell and Kimbrel state that "the treatment (with barium carbonate for removal of sulfate) is simple and consists in maintaining a pH of 9 with caustic soda and quebracho." They caution that concentrations of quebracho greater than 1 lb./bbl. may inhibit the reaction. In another publication&apos;, a pH of 10.5 is considered "the maximum desirable," and the indication is that as much as 2.5 lb. quebracho per barrel may be present in the particular mud under discussion. Lancaster and Mitchell5 state that appreciable amounts of phosphates in the mud will inhibit the reaction with barium carbonate and that the phosphate treatment should be discontinued at least 24 hours before addition of the carbonate. Experimental work was initiated to ascertain the factors involved in using barium carbonate for the removal of sulfate contamination in drilling muds. While the experimental data herein reported are limited, they focus attention on the pertinent factors which must be considered for successful treatment. These factors are discussed from a practical and a theoretical view, the latter being supported by equilibrium data found in the literature. Further, it will be appreciated that the factors involved in this specific study will be closely analogous to those in certain of the other chemical treatments which involve a precipitation of the soluble contaminant. A thorough comprehension of these factors should result in a more fruitful application of this type of chemical reaction to the treatment of drilling muds. EXPERIMENTAL A. Reagents Two muds were used during this investigation. For one series of tests, bentonite suspensions were prepared by dilution of a stock suspension containing 8 per cent by weight of bentonite (Aquagel). For another series, a 6.4 per cent ben-tonitic mud weighted to 9.7 lb./gal. with barium sulfate (Mag-cobar) was used. Distilled water was used in all preparations. The quebracho (72% tannin extract) was obtained from the Thompson-Hayward Co. of Tulsa and contained 11.4 per cent moisture (105 C.). All other materials were reagent grade, and concentrations were corrected for water of crystallization, if any. All concentrations are expressed in pounds per barrel (42 gallons). B. Technique The systems — either mud or water — were contaminated with either sodium or calcium sulfate after treatment with the desired amounts of sodium hydroxide and quebracbo. For treatments with barium carbonate an approximately 3-fold excess (5 lb./bbl.) was used over that computed to be required to precipitate all the sulfate as barium sulfate. Barium hydroxide was used in concentrations of 2 lb./bbl. — about

Jan 1, 1949

By G. L. Kehl, Emilo Jaraiz F., J. S. Brett

The transformation of eutectoid beryllium bronze has been quantitatively investigated at 550° and 592°C, the temperature region where the products of p decomposition are a fine lamellar eutectoid and a coarse lamellar aggregate which replaces the fine eutectoid with prolonged annealing. Metallographic evidence indicates that the coarse lamellar aggregate forms preferentially in the most densely lamellated regions of the fine eutectoid and favors the hypothesis that the development of the coarse lamellar aggregate in the fine eutectoid is due to the occurence of a cellular segregation reaction. WHEN eutectoid beryllium bronze (Cu-94 pct, Be-6 pct) is isothermally transformed at high temperatures in the and y region after quenching from the fl field, the principal initial decomposition process is G one of growth of approximately spherical nodules composed of a number of lamellar colonies of the a and y phases. After the initial reaction has proceeded substantially or completely, depending on the transformation temperature, a second reaction occurs wherein the fine lamellar eutectoid is replaced by a coarser lamellar aggregate composed of the same oand yphases.&apos; This reaction is not simply a spheroidization of the initial fine eutectoid but the nucleation and growth of a coarser, structurally different, and more stable distribution of the @and yphases. Fig. 1 illustrates the replacement of the initial fine lamellar structure by a coarse lamellar aggregate. The a phase is the dark mottled constituent; the light constituent the y phase. The phase diagram for the copper-rich end of the Cu-Be system2 is shown in Fig. 2. The a phase has the face-centered cubic structure characteristic of copper-rich solid solutions. The B phase is a disordered body-centered cubic structure, while the y phase is body-centered cubic, ordered (CsC1, B2 type). A. viswanathanS investigating Debye patterns of Cu-6 pct Be discovered that a transitory phase appeared on very rapid quenching from the /3 region which was absent when the quenching velocity was moderate. The phase could be assigned a body-centtred cubic structure with a lattice parameter of 2.876. Tempering at 100°C for 2 hr after quenching resulted in complete disappearance of the phase. The work of Fillnow and Mack&apos; is the only previously published study of the isothermal transformation of eutectoid beryllium bronze. Their study elucidated the nature of decomposition at various subcritical temperatures in an exploratory fashion. The purpose of the research reported in this paper was principally to obtain quantitative information on the isothermal decomposition of the fl phase and to clarify the relationships existing between the fine lamellar eutectoid and the coarse lamellar aggregate. EXPERIMENTAL PROCEDURE The material used in this investigation was an almost eutectoid Cu-Be alloy bar furnished by D.J. Mack. The alloy had been melted under a protective carbon cover and centrigugally cast into a graphite mold preheated to 490 "C. Segregation was minimized by violent agitation during melting and pouring. The analysis of the casting was 93.85 pct Cu, 5.60 pet Be with traces of Si, Mg, Mn, Co, and Al. To determine the minimum soaking time necessary to insure specimen homogeneity, a number of specimens were held in the P region at 788OC for times fron 1 min to 12 hr and isothermally transformed at 550°C. Specimens betatized less than 12 min exhibited partial transformation at times shorter

Jan 1, 1961