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By J. E. Sherborne, P. H. Jones, E. C. Babson

A study of the Chapman zone in the Richfield field, Orange County, California, indicates that the quantity of oil recovered by present methods will be only a small portion of the oil originally in place. Since the volume of residual oil is believed to be of large magnitude, an experimental water-flooding operation has been initiated in order to determine whether water-flooding offers promise as an economical method of recovering some of this residual oil. A single injection well was drilled between old producing wells, and a water-treating plant using alum flocculation and chlorination was designed and built. Water has been injected into the input well for six months at rates in excess of 100 bbl. per day. Production from one of the neighboring wells has increased materially, the oil production having risen from 7 to 30 bbl. and the water From I to 40 bbl. per day. While definite conclusions regarding the economic success of water-flooding in the Chapman zone are not justified at this time, it has been demonstrated that water can be injected into the zone on a sustained basis and that this water will displace appreciable quantities of oil from the sand. Introduction As a result of an investigation of subsurface conditions in the Chapman zone of the Richfield field, it was concluded that ultimate oil recovery from this zone would probably be low and that natural water encroachment was so localized as to be of little importance from a recovery stand- point. Furthermore, it was found that in many portions of the zone the wells were approaching an unprofitable level of production. When these data were presented to the management of the Union Oil Co.; their reaction was that an attempt should be made to develop methods of recovering at least a portion of the large quantity of oil remaining in this zone. After some investigation, it was decided that wafer-flooding offered the most likely means of accomplishing this end, but reservoir conditions in the Chapman zone differ so widely from those encountered in any of the flooding projects described in the literature that it was difficult to evaluate the probability of success. Despite encouraging results from laboratory tests, it was not even certain that water would displace an appreciable volume of oil from the Chapman sand under reservoir conditions. Therefore, it was decided to initiate a small-scale project, for two purposes: first, to determine whether water would displace oil from the Chapmall sand and, second, to obtain information and experience for future operations if water-flooding appeared to be a promising method of secondary recovery. Reservoir Data The Chapman zone is the upper of the two producing zones in the Richfield field, being found at depths from 3000 to 3700 fi.. The productive portion of the zolle consists of a large irregularly shaped sand body, which is more than 400 ft. thick at the top of the structure. As the margin of the field is approached, the sand is replaced

Jan 1, 1945

By J. S. Aronofsky, H. J. Ramey

Potentiometric model studies of the five-spot water flood to determine the influence of mobility ratio upon injection or production histories are described. The results suggest a method for the correlation of data from field pilot tests for the estimation of an effective mobility ratio and its effect upon field water floods. The effect of the well spacing-to-well radius ratio upon production histories is presented. A method of accounting for this factor is suggested. The influence of injection (or production) rates and injection and production well pressures upon production histories is shown. The five-spot well pattern was investigated for water-to-oil mobility ratios of 0.1 to infinity. INTRODUCTION It has been well established that mobility ratio has an important effect upon flood patterns.1,2,3,4,5 It should be equally apparent that injection and production histories must also be influenced by mobility ratio. However, none of the articles referred to above mention the importance of being able to predict the effect of well pressures (or injection rates) during the entire time history of a waterflood operation. A complete description of production histories (the terms "injection" and "production" are synonymous for the steady-state model under consideration) would provide values for well pressures and interface positions at any time for a specified injection rate. conversely, if the waterflood problem is specified in terms of a constant injection well pressure, then it would be desirable to know the injection rate and interface positions at any time. This paper describes the results of potentiometric model studies which were used to analyze the influence of mobility ratio on injection or production histories. A method is presented for calculating production histories over a range of ratios of well spacing-to-well radius. The basic method described in this paper to evaluate production histories is to: (1) determine interface position as given in Ref. 1, and (2) measure electrical current and voltage drop for each interface position. It should be mentioned that the current state of knowledge on flood patterns as affected by mobility ratio shows that significant discrepancies exist between the results of various investigators2,3,4,5. It is beyond the scope of this paper to discuss the reasons for such discrepancies. However, the method of determining production histories presented in this paper could be applied to any of the swept-area patterns presented in the literature. All results given in this paper are based on a set of swept areas obtained by the potentiometric method. Potentiometric analyzer technique is adequately described in the literature, but the basic assumptions involved in work of this nature bear repetition. It is assumed that: 1. A distinct oil-water interface exists in the reservoir; only water is mobile in the region behind the interface (water zone) and only oil is mobile in the region ahead of the interface (oil zone). 2. There is a fixed mobility value, (k/µ) w associated

Jan 1, 1957

By Grover J. Holt

A detailed description of the many variations in iron mining and transportation practice in Minnesota would require much space. Since a fairly detailed description of the practices then in use was published in the guidebook issued in connection with the meeting of the Institute on the iron ranges in 1920, and subsequent developments have been described by E. E. Hunner, M. H. Barber,2 and A. E. Anderson, J. M. Riddell and G. J. Holt,³ it will not be necessary here to do more than review the highlights of current practice. Details on any points of interest can be obtained through correspondence with the operators involved. † The iron ores of Minnesota, which have been formed through enrichment of the iron formation in which they occur, largely by the removal of silica, are usually covered by a blanket of glacial drift known locally as "surface." Surface material, including sand, clay, hardpan and boulders, makes up the greater portion of the stripping in open-pit operations. In some instances, stripping also includes taconite and paint rock," directly below the surface material and overlying the ore. Tacenite is the iron formation, a ferruginous chert with inter-bedded slate layers. :'paint rock" is a local term for oxidized slate layers inter- bedded in the iron formation, high in phosphorus, alumina and moisture. The iron ores fall into two classes: (I) direct shipping (merchantable ores or ores requiring no treatment except possibly crushing or screening to make an acceptable sized product), and (2) ores requiring beneficiation (such as sintering, drying, washing, jigging, high-density treatment, or magnetic separation in the case of magnetite). The Mesabi Range produces chiefly soft Bessemer and non-Bessemer ores. The Cuyuna Range produces mainly low-manganese brown ore and high-manganese black ores, with some iron ore. The Vermilion Range yields mainly Bessemer and non-Bessemer iron ore, with some hard or lump ore that finds use in the open hearth. Open-pit mining is limited to the Mesabi and Cuyuna Ranges but underground mining is done on all three. The choice of mining methods is determined by the relative economics of overburden-removal and shaft-mining costs. Stripping Practice Common practice has been to remove the bulk of the overburden during the winter season and to mine during the summer, In- the present emergency many operators are forced to forego the economies attained by year-round utilization of paper. and to equip for, and carry on, stripping and mining simultaneously. In the normal years or lean years to come, most properties probably will be overequipped and high depreciation charges Will have to be absorbed.

Jan 1, 1943

By C. H. Ma, J. S. Makris

This paper describes a modified X-ray diffraction microscope wzethod based on the general principles of Berg-Bawett's Method, Lang's Method, and Woosters1 Technique. This new method may be used for stationary or oscillatory photomacrographs, with both reflection and transmission techniques. In the stationary technique, a small point-source of a divergent X-ray beam of white radiation is used; in the oscillatory technique, a monochromatic divergent beam is employed. The chief advantages of the method described herein are that only approximate alignment of the Bragg angle -of-interest is needed during exposure, and that a large portion of a crystal-specimen surface can he irradiated. In recent years, the study of dislocations through X-ray diffraction microscope techniques has received considerable attention as concerns the per,fection of single crystals. Very promising results have appeared in the literature.'-' These techniques are very useful when the dislocation density of a crystal is near 105 per sq cm or lower. The principle of X-ray diffraction microscopy is based on the differential effect of X-ray primary extinction between the distorted parts and the perfect parts of a crystal. When an X-ray beam impinges on a set of planes of a crystal at the correct Bragg angle, diffraction of X-rays will occur with a 90-deg phase shift of the diffracted beam. This once-diffracted beam still forms the correct Bragg angle with the planes ahead of it, if the planes are not distorted. Thus, part of the strength of the once-diffracted beam is rediffracted and the beam continues to travel in the direction of the primary X-ray beam. This twice-diffracted beam not only takes away part of the strength of the once-diffracted beam, but also causes destructive interference with the primary beam because it now is exactly 180 deg out of phase with the primary beam. As the primary beam goes farther and farther into the crystal, its intensity is continuously weakened. Asa result, the ultimate X-ray diffraction power of a set of undistorted planes is largely extinguished. This phenomenon is called primary extinction.1,2'4 If the set of planes ahead of it is distorted, the once-diffracted beam will have less chance to be rediffracted, because it could not meet the exactly correct Bragg angle for rediffraction. If a part of the beam does rediffract, this twice-diffracted beam is not exactly 180 deg out of phase with the primary beam, and thus it causes less destructive interference. As a result, the registered X-ray diffraction power of the distorted part of a crystal appears stronger than that of the perfect part. Thus, point-by-point contrast of a diffraction image is theoretically possible from a crystal containing dislocations. Two most popular X-ray diffraction microscope techniques today are Berg-Barrett's Method and Lang's Method. Both of these techniques require a

Jan 1, 1964

By C. A. O’Connell

Surface exploration drilling at Mufulira started in 1928, with drillhole No. 1 intersecting ore near the eastern fringe of the deposit. Subsequent drilling along strike intersected ore until the western fringe was fixed some 7500 ft west of drillhole No. 1. Further intensive drilling down dip disclosed a large triangle of ore with its apex 3350 ft deep. It contained approximately 11 6 million tons of ore at 4.41% total copper in three superimposed orebodies. The east and west limits of the orebodies were presumed to have a pronounced rake to the north with a strike length of 8000 ft. Subsequent exploration underground seemed to bear out this presumption to the 1150 ft level. In 1947, attention was directed to the area west of the known orebodies in conjunction with plans for increased production and increased depth of the mine workings.

Jan 12, 1962

FEW whose good fortune it has been to gaze on the Utah Copper mine but will agree that it is one of the two or three most magnificent man-made spectacles in the world. Skyscrapered Manhattan Island perhaps is more inspiring; but there the effect is obtained by aggregating a thousand separate units. The Utah mine is a single thing- the biggest thing that men have made. By the end of 1931 there had been moved at Utah 222,000,000 cu. yd. of material, including ore and the waste rock that overlay it. This figure will be increased at an average rate of nearly 20,000,000 yd. per year. Excavations for the Panama Canal are estimated at 232,300,000 cu. yd., but the Canal is 50 miles long, and it is impossible to obtain a comprehensive view of the whole project at one time. The spectator, on the other hand, need only walk part way up the east slope of Bingham Canyon to see unfolded before him the whole panorama of the great copper mine. In the foreground is a huge pit bottomed for the time being 100 ft. below the normal floor of the canyon, which also is the elevation of the main railroad yard. Here from 500 to 800 standard steel railway cars, each of 80-ton capacity, are assembled daily to carry the ore to the concentrators. But the main part of the mine and that from which ore is now coming lies above this level. As can be seen in the accompanying photograph, a series of terraces or benches reaches to the top of the mountain that projects between the main branch of Bingham Canyon and Carr Fork. From bench A (the yard level) to bench W is a vertical distance of 1500 ft. In height the benches vary from 40 to 70 ft. and in width from 30 to 450 ft. The lower benches, as they skirt the mountain,

Jan 1, 1933

By Ernest Gayford

When the United States Government started buying gold at varying prices per ounce, set by the President and the Treasury Department, the gold miner found himself facing new conditions, as gold became a commodity with a fluctuating market price. While it was self-evident that the miner was to receive more for his gold than the old established price of $20.67 per ounce, there was an element of uncertainty, which made it difficult, and perhaps dangerous, to decide to invest his time and money to produce gold, especially if the profit would represent only the difference between $20.67 an ounce and the new price as set from day to day by the Government. When, however, on Jan. 30, 1934, the United States went off the gold standard, the price of newly mined gold being rather definitely set at $35 per ounce, with some assurance that the price would be maintained at or near this figure for a long time to come, the gold miner was justified in revaluing his property on the basis of the new price, and the prospector was offered inducement to spend his time and energies hunting for new mines, or going back to old locations previously abandoned as of doubtful value. It is interesting to see what this new price means to the producer of newly mined gold, and how much of the increase is passed on to the producer. It will be found that, as with the base metals, the nearer he can get to producing a finished product himself the greater his reward will be; the net returns for bullion being necessarily higher than for the same amount of gold shipped in concentrates to the smelter. Bullion can be shipped to the United States mints or Government assay offices under the following terms and conditions. An affidavit must accompany the shipment, stating, among other things: 1. The source of the gold; whether ore, tailings or placer. 2. The tons of ore, tailings or cubic yards of gravel from which the shipment was recovered.

Jan 1, 1935

By D. Perry, G. W. Binkley, G. K. Dumbauld, F. A. Brooks

A new cementing technique has been developed which is particularly applicable to permanent-type well completion operations. The technique makes use of the accelerating effect of calcium chloride on setting time and strength development of cement cake deposited in squeeze cementing. An unique feature is that the accelerator is applied after the unaccelera-ted cement slurry has been squeezed and the excess has been reversed from the well. Laboratory data on the accelerating effect of calcium chloride applied to the fi1ter cakes of three low-water-loss cementing compositions demorzstrate that the procedure results in relatively rapid development of strength and impermeability of the cement cake. Simulated squeeze-ceinenting tests made in the laboratory likewise corroborated the practicality of the procedure. The laboratory tests showed that a newly developed oil-emulsion cemerzting composition is more susceptible to acceleration of set than are modified cements containing high percentages of bentonite. The acceleration procedure has been used successfully in field operations. INTRODUCTION Nature of Problem In squeeze-cementing operations, a substantial amount of time is consumed in waiting on the cement to develop strength after it has been squeezed into the well. Frequently, an interval of 18 to 24 hours or longer is required for the development of strength sufficient to prevent failure of the cement during subsequent operations in the well. Reduction of this waiting-on-cement time offers appreciable savings both in time and in money. A particular type of squeeze-cementing operation to which an increasing amount of attention has been given is encountered in permanent-type well completion operations wherein perforations are to be squeezed off1. In this procedure, it is customary to pump the cement slurry down the tubing and out into the perforated section through a retractable extension pipe. Squeeze pressure is then applied, which forces the cement slurry into the perforations and causes the build up of a compact filter cake of cement within the perforations. The excess slurry remaining in the hole is then removed by reverse circulation. The extension pipe is then retracted, and, if a new interval is to be perforated, a perforating gun is run through the tubing. The newly perforated interval may then be tested by swabbing. In such operations, it has been customary to allow approximately 20 hours or so for hardening of the cement squeezed into the perforations. This time interval is usually measured from the time that the cement is reversed out of the hole to the time that subsequent swabbing is started. If the cement has not developed strength at the commencement of swabbing, the pressure differential caused by swabbing results in failure of the squeeze job. At the time that the work described in this report was initiated, particular consideration was given to the reduction of waiting-on-cement time in squeeze cementing by the permanent-type completion technique. Consequently, much of the experimental work was directed to this specific objective, though the process which was developed for acceleration of strength development has possible application in other than permanent-type completion operations. Method of Attack Although quick-setting cements

Jan 1, 1957

By Theron Wasson

The oil and gas fields of Michigan that have been under development since 1925 are in an area that extends across the middle of the lower peninsula from northeast to southwest, a distance of about 200 miles, and with a width of about 80 miles. In 19 years 70 fields have been discovered. Most of these are relatively small when compared with other oil-producing areas. This is borne out by the fact that since the first wells were drilled these fields have produced a total of only 204,000,000 bbl. However, Michigan is still maintaining its production, for during the past five years the annual production has remained fairly constant at approximately 20,000,000 bbl. Production for 1943, as reported by the Bureau of Mines, was 20,682,000 barrels. Roughly, one third oi Michigan's production in 1943 came from the Reed City field, which was discovered in 1941. During the year, 237 oil wells were completed in Michigan in 1943. The decrease of 56 from the 1942 total is probably due to the continuance of Government regulations requiring a 40-acre spacing pattern over most of the state. Fig. I shows the principal oil and gas fields of Michigan, and the columnar section, Fig. 2, shows the principal producing horizons in relation to the section drilled. The data of Table I and Table 2 have been carefully checked with previous reports to eliminate errors. Six new producing areas were discovered during 1943 and five areas discovered in 1942 were developed during the year. Both the new discoveries and the 1942 discoveries that were developed appear to be small and relatively unimportant. Goodwell Field.—The best discovery of the year is the Goodwell field, T. 14 N., R. 11 W., Goodwell township, Newaygo County. This small structure was located by core testing done by The Pure Oil Co. in 1942 and early 1943. The first producing well, C. R. Harris No. I, was completed on July 5, 1943, ill the Traverse limestone at a total depth of 2742 ft., with ail estimated potential of 1100 bbl. per day. By the end of the year, 18 wells had been completed in this field and approximately 281,000 bbl. of oil produced. The field operated under proration of 262 bbl. per day per well from Oct. I to Dec. I; 150 bbl. per day per well after that date. Woodville Field.—The small Woodville pool, T. 15 N., R. 11 W., 3 miles north of the Goodwell field, was discovered by core testing by the Ohio Oil Co. The discovery well was completed on May 5, 1943, flowing 650 bbl. of fluid, including 18 per cent salt water the first 18 hr., from the Traverse limestone at a depth of 2810 to 2815 ft. Seven wells had been completed by the end of the year and 67,000 bbl. of oil had been produced. Development is now practically at a standstill because further drilling does not aDDear economically iustified.

Jan 1, 1944

By James H. Gardner

It is a striking fact in the domestic oil statistics of 1926 that with an increase in production of 13,000,000 bbl., there was nevertheless a lowering of both crude and gasoline stocks. It was the first reduction in the last eight years. In 1918, the last year of the war, stocks of crude and refined products were lowered 16,000,000 bbl., but in the following seven years stocks were increased 350,000,000 bbl., due largely to the phenomenal crop of major pools discovered in 1923. The big pools of that year coming as they did through some curious coincidence unprecedented in the oil industry, not only piled up a sudden increase of stocks at a time of large imports but they continued to add their quota to an increase of storage until 1926. With an increase in crude production, according to the Oil and Gas Journal, from 760,000,000 bbl. in 1925 to 773,000,000 bbl. in 1926, and an increase in cracking facilities of about 30 per cent., there was a draft on storage of 22,300,000 bbl. of crude and 1,000,000 bbl. of refined. Crude and refined changed from a stock surplus of 29,130,000 bbl. in 1925, to a deficit of 23,300,000 bbl. in 1926, or a differential total of 52,430,000 bbl. With a stock reserve of 541,700,000 bbl. of crude and refined oil in 1925, the amount drawn from storage was not large in percentage but it marked an important contrast with previous years. It meant a year of stability in prices and a sound condition in the industry. The indicated domestic demand increased from 695,120,000 in 1925 to 743,360,000 in 1926, (7 per cent.), 1 per cent. of which was due to California fires. Most of the gain in consumption was due to the increased demand for gasoline. There was little comparative change in the combined imports of crude and refined oil. There was an increase in exports of 17,200,000 bbl. (1.5 per cent). A petroleum balance sheet for 1926 and a comparativl sheet for the last two years, production in the United States by major districts and pools, and a list of imports are given in Tables 1 to 5, inclusive.

Jan 1, 1927

By Elmars Ence, Harold Margolin

The partial isothermal section of the Ti-Cu-Zr system at 750°C has been studied. The crystal structure of Ti2Cu has been detevnlined as tetragonal and when expressed as face-centered tetragonal, a = 4.164, c = 3.611 A, and c/a = 0.867. TITANIUM systems in which ß-titanium decomposes eutectoidally into a and a compound rather readily are known as active eutectoid systems. Recently in active eutectoid alloys based on the Ti-Cu system, and containing additionally A1 and Zr, it has been found that zirconium may produce both moderate weakening and marked strengthening at elevated temperatures.' In order to obtain some insight into the behavior of zirconium, an attempt was made to determine whether compounds of the type Tix Zr and TixZryCu exist. Only results of the Ti-Zr-Cu studies are reported here since data on Ti-Zr alloys will be presented in a separate publication. EXPERIMENTAL PROCEDURE Alloys were nonconsumably arc melted in argon atmosphere as 15-g buttons, prepared from materials of the following purities: Bureau of Mines electrolytic Ti — Bhn 63 OFHC copper Reactor Grade Zirconium Bhn .C 150 Prior to alloy preparation the electrolytic titanium was premelted to avoid excessive spattering of the charges during melting. The weight losses during melting did not exceed 1 pct of the total weight of the charge. The alloys prepared are listed in Table I together with analyzed compositions. in cases where they were determined. Specimens for heat treatment were wrapped in molybdenum sheet, annealed in argon-filled quartz capsules, and quenched by breaking the capsules under iced brine. About 1 to 2 sec are required to remove the capsule from the furnace, drop it into the iced brine and break it. Because of the insulation effect of the quartz, this delay in quenching should not produce a large drop in temperature. In many instances, no difference or little difference has been detected between the same specimen quartz capsule quenched or directly quenched in vacuum by an impinging stream of water.' Ti-Cu-Zr alloys were homogenized for 48 hr at 825°C prior to annealing at 750°C. Annealing for 5 days at 750°C produced the same results as 11 days at temperature and it was therefore assumed that 5 days was sufficient to establish equilibrium. Titanium-copper alloys were homogenized for 40 hr at 900°C prior to heat treatment for 6 days at 750°C. Specimens for metallographic examination were electropolished and etched with the following solution:

Jan 1, 1962

By L. J. Parkinson

IN striking contrast to American mining engineering schools, in Europe a new president, known as the Rektor Magnificus, is elected each year or alternate year. An exception is Italy, where election is for a period of three years. The Rektor, who is elected by the full professors, must also be a professor and full-time member of the faculty. In most cases there is a Senate, composed of 5 to 14 full professors, some elected and some appointed, which controls the Rektor in policy decisions, but in some institutions there is no such controlling body. In the same way deans for each faculty or college are selected at the same intervals from among the full professors concerned.

Jan 1, 1958

By H. D. Kessler, Joseph B. McAndrew

WHEN there is occasion to make structural use of metals at temperatures above 900°C (1652°F), the choice of alloys is severely limited, and those materials which meet special requirements as to density, strength, toughness, and resistance to creep, oxidation, or fatigue at such temperatures are at a premium. Any new type of high temperature alloy which is found to be outstanding with respect to several of these properties is therefore likely to find special applications for which it is uniquely advantageous as compared to other alloys. Such is the case with the 7 titanium-aluminum alloys. This y phase is an intermediate phase based on the composition TiAl, and extends from about 35.5 to 44.5 wt pct Al at temperatures up to 1000°C, above which the field broadens to include 60 pct A1 at 1340°C.' The alloys of principal interest have a narrow melting range, with 7 forming by the peri-tectic reaction, melt + ß=y at about 1460°C. Unlike most intermediate phases, the binary alloys containing titanium and aluminum in approximately equiatomic proportion possess low room temperature hardness,' in addition to which they have low density, good resistance to oxidation, and relatively high modulus of elasticity.' Unpublished work done at Armour Research Foundation showed

Jan 1, 1957

By John Chipman, Karl L. Fetters

Tax relationship between the composition of the slag and that of the underlying metal during the refining of a heat of liquid steel may best be studied in the light of the two broad physicochemical concepts of equilibrium and reaction rate. Actual steelmaking processes, typified by basic open-hearth practice, involve such complexities of operating variables that it is impossible to distinguish with any degree of certainty between the general limiting conditions imposed by chemical equilibrium and the effects associated with rates of diffusion or of chemical reaction. Further advances in the physical chemistry of steelmaking will depend upon our ability to distinguish clearly between these two kinds of effects, and the experimental work that must be done falls naturally into two classifications. The first is the study of chemical equilibrium that cannot be carried out with assurance under operating conditions but must be done in the laboratory. The second is the subject of rates of reaction and diffusion and the mechanism of the process as a whole, which can best be studied under operating conditions. The latter is not entirely independent of the former, since its interpretation often requires a knowledge of the equilibrium state. It is the purpose of this and of several papers that will follow to present the results of laboratory investigations of equilibria involving liquid steel and slag. Open-hearth slag is a complex mixture containing at least eight major components and perhaps twice as many whose influence may be classified as probably minor. It is not surprising that progress toward a complete understanding of such a material at high temperatures has been slow. Attempts to apply the established principles of physical chemistry to the behavior of the individual components of this mixture have been beset by an almost complete lack of data on its chemical properties in the liquid state. This has necessitated the adoption of various methods of approximation based upon such assumptions as, for example, that for a given component the ratio of its mol fraction in the slag to that in the metal is a constant, or that the molecular composition of the liquid slag is the same as its crystalline constitution after solidification. From the thermodynamic viewpoint, such assumptions are merely useful dodges, which enable one to hazard a guess as to the magnitude of the more fundamental quantities, the chemical potentials and activities of the components of slag. The problem of determining the activity of each substance in an eight-component system seems too complex to be undertaken without the aid of generalizations derived from experimental data on similar systems containing a smaller number of components. Accordingly, it was planned in the present investigation to study the equilibrium of molten iron with the simplest

Jan 1, 1941

By Henry D. Hibbard, Edward L. Ford

The process of making washed metal now followed is in principle that described by Holley before this Institute in 1879, as the Krupp washing process. Sir Lowthian Bell also experimented extensively in England during 1877 and 1878 on refining iron and joined his interest with Krupp, the process being often referred to as the Bell-Krupp process. The only plant in this country now operating this process is that of the Brier Hill Steel Co., Youngstown, Ohio. This process may be considered as the sole survivor of the numerous methods conceived for refining crude iron, when the removal of phosphorus from steel-making material was the great desideratum affecting large districts. The east coast of England and all northern Germany, the homes of Bell and Krupp, respectively, could at that time make steel only from imported ores. These processes were in use or in various stages of development 40 years ago and all except the Bell-Krupp received their quietus from the development of the basic steel processes, both pneumatic and open hearth. The aim of the early refining processes was, first, the removal of the silicon, which could be done on a sand bottom, and later, the removal of the phosphorus, requiring a bottom which would give or permit a basic slag. The incidental advantages of increased yield and small fuel consumption were not generally recognized or considered; the aim of the later operations was the saving of the difference in value between low and high phosphorus irons, as well as hastening the removal of the metalloids. The chemistry of the washing process follows in part that of the puddling process, and indeed washing might be considered as the first half of puddling, since all the non-ferrous elements of the crude iron, except the carbon, are eliminated and the iron is maintained molten until cast. In puddling, the iron loses its carbon as well, and because of that, its fusion point rises above the hearth temperature; it freezes into a pasty malleable form, and is worked at once by squeezer, hammer, or rolls. Since Holley's paper, important improvements have been made from time to time in both plants and methods for washing iron, and the

Jan 1, 1916

By R. S. Handy

Does hand-sorting of mill feed pay? The fact that the practice is so general would seem to indicate that there must be good reasons for following it; yet, to my mind, the advantage in many cases is doubtful enough to invite a thorough discussion of the subject, in an effort to determine under what conditions hand-sorting does pay. A typical sorting plant in the Cœur d'Alene district handles about 800 tons of mine-run ore per day. The material is run over a grizzly with about 4-in. opening; the oversize is crushed to about 4-in. size and joins the undersize, and the whole product is washed and screened on trommels with about 11/2-in. openings. The oversize from these trommels is spread on a belt and the waste and first-class ore are sorted out by hand, the residue being further crushed, and passes, together with the trommel undersize, into the mill feed bins. About 50 tons of shipping ore and 150 tons of waste are sorted out per day, leaving about 600 tons of mill feed. To sort out this material requires 20 ore sorters and five bosses and repairmen. The normal cost of hand-sorting is about 16 c. per ton of run-of-mine ore, or 65 c. per ton of material sorted out. I believe that straight crushing and milling of the run-of-mine ore, in this case, is not only cheaper, but is metallurgi-cally more economical and efficient than hand-sorting followed by milling of the residue. At one of the Bunker Hill rock-houses, 1250 tons of run-of-mine ore are reduced to pass 30-mm., or about 11/4-in., opening in six hours, requiring five men. The equipment and the power consumed are not greatly different from that required in a sorting plant of the same capacity, and the normal cost of thus preparing the feed for milling is under 3 c. per ton of mine product. The relative cheapness of this method as against hand-sorting is thus clearly established, the saving being about 13 c. per ton. If there is any virtue in, hand-sorting, then, it must lie in the metallurgical results achieved. Possibly the favor that hand-sorting has found is due to a misconception as to what happens to the clean shipping ore if it is sent to the mill. If a mill makes, say, an 80 per cent. recovery on its feed, the hand-sorting advocate may assume that if the hand-sorted product be sent to the mill, 20 per cent. of the metals contained in it will be lost. This, I believe,

Jan 1, 1920

By N. L. Muench, J. S. Osba

Research conducted previously has demonstrated that spectral analysis of gamma radiation from the naturally radioactive elements present in earth materials permits detervination of the relative concentrations of these elements. This research suggested that spectral analysis of gamma radiation resulting from neutron bombardment of elements not nor-mally radioactive might serve to identify these non-radioactive elements, and might permit their quantitative determination. To investigate this possibility, laboratory experiments were conducted in which various earth materials were subjected to bombardment by neutrons from a polonium-beryllium source, and in which the spectra of the resultant gamma radiation were analyzed. The geometry of the lab-ortory system was designed to simulate wellbore conditions. The laboratory work demonstrated that some elements not only can be identified with relative ease, but also can be determined quantitatively. This finding indicates that the use of an intense source of more energetic neutrons may lead to the identification and measurement of additional elements of interest by means of induced nuclear reactions. INTRODUCTION In recent years the applications of nuclear physics to the producing branch of the petroleum industry have become increasingly numerous. One significant development, an outgrowth of nuclear science which is of potential importance in well logging, has been the analysis of gamma-ray spectra of naturally radioactive elements in earth strata. The work of Brannon and Osoba1 has demonstrated that presently available equipment and techniques may be used to determine the relative concentration of thorium, potassium, and uranium in underground strata by means of gamma-ray spectral analysis. Success of the research on spectral analysis of naturally radioactive elements suggested that spectral analysis of induced radioactivity might serve to identify, and perhaps measure quantitatively, those elements which normally are not radioactive, but which become radioactive on neutron bombardment. It was to investigate this possibility that the research described in the following sections was undertaken. THEORY OF INDUCED NUCLEAR REACTIONS Of fundamental importance is the fact that an element, when bom- barded with neutrons, emits gamma rays of energies characteristic of that element. Therefore, in theory, an element may be identified by analysis of the energy spectrum of the neutron-induced gamma radiation. If a neutron impinges upon the nucleus of an atom, any one of several reactions may occur. For identification of elements in earth formations the more important are listed below: 1. The neutron may be elastically scattered, as in a collision between two billiard balls. In this case the total kinetic energy is conserved, and no nuclear radiation is emitted. 2. The neutron may be inelast-ically scattered, as in a collision between two automobiles in which case the total kinetic energy is not conserved. The lost kinetic energy reappears in the form of gamma radiation. 3. The neutron may be captured, in which case the neutron becomes a part of the target nucleus, and a gamma ray is emitted. For example, if the target nucleus is H1, the pro-duced nucleus will be H3, and gamma radiation of a particular energy will be emitted. 4. The neutron may produce nuclear fission, or may enter into miscellaneous reactions which result in the emission of

Jan 1, 1958

By H. J. Beach, W. C. Goins

The laboratory development and field use of oil well cement compositions* with high resistance to drilling mud contamination are described. Resistance is obtained by adding a I-lb mixture composed of three parts paraformaldehyde to two parts sodium chromate tetra-hydrate for each sack of cement. This mixture neutralizes the cement-retarding properties of quebracho and other tannins, starch, sodium carboxymethylcellu-lose, Ignite, and monovalent salts of lignosulfonic acid. The retarding properties of calcium lignosulfonate are unaffected. The decontaminating mixture may be used in common cement (designated Type I by ASTM specifica-tions,' Class A by API Std. 10A2) or in a slow set slurry prepared from common cement by addition of calcium lignosulfonate. No changes in slurry viscosities or thickening times are caused by the protecting reagents. The method has been used in 185 field jobs where an improved success ratio has been obtained in plug setting. INTRODUCTION Field experience and laboratory investigations have established contamination by drilling mud as a major factor in oil well cement failures. During 1955, 12 attempts were required to set six open-hole cement plugs in the Timbalier Bay field, La. Eighteen to 30 hours elapsed between placing and testing the plugs in preparation for sidetracking operations. Considerations of rig time expense required immediate resetting where soft cement was drilled after a reasonable waiting period. Sea water drilling mud was used in each well and daily additions of thinners, usually lignites, had been required. Sodium carboxymethylcellulose had been added regularly to control fluid loss. The 50 per cent plug failures were attributed primarily to contamination by the mud. Similar experiences can be found in other fields along the Texas and Louisiana coasts where drilling muds normally contain large quantities of organic treating materials. Cement contamination was the subject of a survey by the Mid-Continent District Study Committee on Cementing Practices and Testing of Oil-Well Cements of the API.3 Data collected from member laboratories and released in Sept., 1951, reported the effects of a number of drilling mud treating chemicals on cement. The study revealed that many of the additives, notably the organic materials in relatively small quantities, had marked effects on the properties of cements tested. Severe losses in strength and erratic thickening time resulted from small additions of mud treating chemicals such as quebracho, starch, sodium carboxymethylcellulose, and lignite. The report included no recommendations of methods for overcoming the problem. One investigation of the contamination problem reported the successful use of activated charcoal in setting cement plugs after conventional slurries had failed.4,5 The investigation indicated that an optimum concentration of 5 per cent activated charcoal was effective in combating contamination from 16.7 volume per cent of treated mud. Laboratory and field muds were included in tests and contained varied quantities of ode or more of the following: quebracho, caustic, starch, lime, and calcium lignosulfonate. The function of the charcoal appears to be physical, removing the organic materials by adsorption. The method may be employed in API Class A or Class D (unretarded slow set) cements. The chemical approach presented here is based on

Jan 1, 1958

By Gifford E. White

EXPLANATIONS of the basic procedure for making earth-conductivity studies by the Eltran method have already appeared in several places.1,2,3 In its essentials, this method consists of applying step functions of voltage to one pair of earth grounds and measuring the transient potential resulting at a separate pair of ground points. As previously pointed out,4 the transient potential resulting from a suddenly applied steady voltage is the indicial transfer function of Carson,5 which has been extensively studied in network theory. [ ] The discussion here, with one special exception, will ignore the problem of how the physical configuration of the earth affects the transient response voltage; it appears that this phase of the problem has been solved in only a few special cases having any direct bearing on the prospecting problem. Entirely distinct from the potential theory aspect of the conductivity problem is the interesting material that can be had from studying the well-known network relations between cause and effect in linear circuits, and thus deducing criteria for the application of the several experimental methods available. To do this, only one assumption need be made about the nature of the earth. The earth is to be considered a linear conductor within the tolerance of ordinary measurements. The discussion will be restricted to collinear electrode configuration like that of Fig. I, since this is the only type of spread practical for use with driving currents that vary with time. Here one pair of grounds carries the driving current, and in line with these and external to them is a [ ] pair of potential probes. The problem will be to consider the relation between the different voltages appearing between the potential circuit terminals when various types of driving voltage sources are inserted in the current circuit. Suppose that the grounding points G1 and G2 make good contact with the earth, and that a battery of sufficient voltage to produce one ampere of direct current is introduced into the current circuit by the closing of a switch. The potential transient response to such a voltage can be measured by taking an oscillogram at the potential circuit terminals, giving the time function that has been called A(t).4 This time function has been solved for analytically in the case of a homogeneous earth,6,7 and the

Jan 1, 1941

By Milo W. Krejci

The plant and quarries of the Inland Portland Cement Co. are located at Metaline Palls, Wash., about 128 miles north of Spokane, on the Pend Oreille river, and within 10 miles of the Canadian border. The plant is one of a chain of cement plants controlled by the Lehigh Portland Cement Co., of Allentown, Pa. Work on this plant was commenced in June, 1910, and was completed in April, 1911, but on account of some delays in the construction of the power plant, the works were not put into operation until August, 1911. Since then it has been in continuous operation and has furnished the Inland Empire with a high grade of cement. Fig. 1 is a view and Fig. 2 is a plan of the works. Water Power Development.—The source of the water supply for the hydro-electric plant of the Inland Portland Cement Co. is Sullivan lake, a body of water approximately 5.5 miles long and' 0.5 mile wide, situated in the Kaniksu Forest Reserve. A wooden crib dam was installed so as to raise the elevation of the lake 25 ft., and the additional storage capacity was taken up by the diversion of Sullivan creek into the lake by means of a wooden flume, 0.25 mile long, 6 by 8 ft. in cross-section, and a ditch 1,200 ft. long. The water from the lake follows the natural water course to an intermediate storage reservoir, which was created by the construction of an earthen dam. This pond was used in connection with the saw mill which was installed at this point. Besides the earth dam, there was also built a crib, at the point shown in the sketch map, Fig. 3. This crib dam is 35 ft. high. From this point the excess water follows the natural course of Sullivan creek to the Pend Oreille river. The water is taken from this intermediage storage by means of a 6 by 8 ft. wooden flume approximately 13,000 ft. long. This flume is built up on the side hill, piling being driven most of the way on

Jan 1, 1914