Search Documents

By Cyril Stanley Smith, Earl W. Palmer

A study of the precipitation-hardening of copper steels1 led the authors to investigate malleable iron containing copper, for the low-carbon ferritic matrix in malleable iron should lend itself admirably to precipitation-hardening. It was soon found that in addition to rendering malleable iron susceptible to improvement by precipitation-hardening treatments, copper has another potentially useful effect as an accelerator of graphitization. Brief mention of these effects was given in a general paper by Lorig and one of the present authors2; the present paper gives further details on the graphitization and precipitation-hardening effects only. After the completion of this work a paper by L. Lykkin3 appeared, confirming the authors' conclusions regarding graphitization. Material Used After some preliminary heats had been made in the laboratory to determine the effect of copper, several castings from commercial air-furnace heats were obtained, and data from these alone are given here. Part of the metal was poured directly and part was treated in the ladle with the desired amount of copper before pouring. Green-sand molds were used, each holding two tensile test pieces of the form adopted by the Malleable Iron Research Institute, or two bars for graphitization studies, 5/8 in, in diameter and 9 in. long, fed through two enlarged sections equidistant from the middle and ends of the bars. Risers of suitable size insured sound castings. Tensile tests were made on the castings after commercial mallealleizing and after special heat treatments to be described. The analyses of the white irons are given in Table 1.

Jan 1, 1935

By J. R. Kyte, L. A. Rapoport

The material balance equation for partiai or complete 1:trter-drivc reser1,oir.s been re-arranged to include a pressure irrferferencr ternr. This pressure interfernce term was ohtained from the theory established hy Morinda. A .successful progranl deissed to solve the resrclritlg c,qrration in a few hours on a nleelitr .sizeti, digital compuier. No prior knowdelge of the properties of the eqrrifer is required in the solution. 7' ri~rl calculations areatle using various assumed con!binuiions of value of the constant expretsing the qquifer properties correspoinds to the best fit ohtained between observed and calculated field history. Details of the method of calculaion are illus trated by an example. INTKCDUCTICN A method 01' calculating the material balance equation for a partial water-drive reservoir completed in an aquifer has been described in the literature." Pressure interference i'rc,m other pools iocated in the same nquiucr is not taken into account in this solution. When present, the pres- sure interference effect must be included in order to make a complete performance analysis. A correction for this effect has been developed using the theory cstahlished by Mor-tada.' Manual calculation of the material balance for water-drive reservoirs is a formidable task. Such manual ca1culation when interference eflects are includcd would be impossible to completc in any reasonable time period. However, a medium-sized stored program, digltal conlputer can he used satisfactorily. The method is described in the following sections. THECKETICAL CONSIDEKATIOhS The material balance equation for a reservoir producing by partial or total water drive, as proposed by Van Everdingen, This relationship is linear for Z/a from which thc slopc, Z, and the intercept, N, can be obtained by the least-squares method from the data points. It is not necessary lo know the aquifer properties to uktain oplimum values tor 2nd IV. Various assumptions are made tor At,,: where 11 is production time, seconds (oilfield between the equal successive time intervals into which the history is divided. t,, h It, times the number of equal time periods from i.e.. the total dimen-sionless time interval from It is noted that the dinlensionless time interval, At,,, involves all the relevant aquifer properties. Accordingly, any assunlption of is an assumption of the combined aquifer properties which pertain to the solution of the equation. Deviations of the data points from a straight line arc calculated for each assumption of and the value of A, correspond ing to the minimunl deviation is chosen as the optimum solution. This method is described in Ref. 1 and 2. Thc material balance solution is usually made with an initial assumption that the reservoir being studied is located in an infinite aquifer from which there are no other withdrawals. Deviation of the points by amounts greater than can be attributed to inaccuracies in field data may be the result of: (1) boundary effects of a limited aquifer, (2) pressure interference from othcr pools completed in the .sarne aquifer, and (3) a combination of these effects. Differentiation of these effects can be made only on the basis of geologic data. Pressure interference from other fields will result in a pressure drop at the original oil-water boundary having an interference component, The measured instantaneous pressure drops at the oil-water

By R. C. Weed

LEACHING in place at Cananea began in the 1920's on a limited scale. The first plants were small wooden boxes located underground in the Capote and Oversight mines, and output was low. Scrap iron was used as precipitant. Later several other small plants were started up. Leaching was limited entirely to underground areas, and production remained low. The Veta precipitating plant, the first on a larger scale, was put into operation in the late 1920's. After a period of intermittent service it was rebuilt in 1946 and has since been running continuously. In 1943 work on the Colorada open pit was started. This produced 40 million tons of waste, which averaged 0.20 pct capper. When these dumps had aged a few years it was decided to leach them on a large scale, and after considerable research and investigation a leaching system of pumps and pipelines was laid out and installed. At the same time the Ron-quillo precipitation plant was built to treat the copper solutions from the pit dumps. This plant started operation in March 1953. Leaching areas consist of the Colorada pit dumps and various mined out and caved underground stopes. The principal mineral, chalcocite, leaches readily in a weak sulfuric acid solution containing ferric iron. Enough pyrite is contained in the areas to produce an acid-ferric iron solution strong enough to dissolve the copper. Each area is studied to determine the best method of distributing the water over it and the best method of collecting the copper-bearing solutions after leaching has taken place. Water is generally distributed by means of ponds, ditches, and sprays. Spraying has proved the best method of spreading the water evenly; however, in a dry climate some water is lost through evaporation. After passing through the leachable material the solution is collected underground by dams and bulkheads and on surface by dams. An effort is made to give the maximum storage capacity practicable.

Jan 1, 1957

From the cold Pacific waters in June rolls a blanket of white clouds that tucks up around the mountains at around 8000 or 9000 ft. This is the way it happens in southern Peru and so the mining operations and daily living at Toquepala have an ethereal quality not often encountered. Besides looking down on the clouds from the brightly sunlit mountain tops, one can discern the trace of a different era in the brown barren mountain slopes. This trace is like a delicate net laid over the surface of the earth-a criss-crossing of innumerable trails that are so omnipresent, yet faint, that the local people have long since ceased to notice them. It is difficult at first to ask about them because no one understands what you are talking about. It finally comes out though, that the markings are indeed trails, but fossil trails made by animals in times when they were in abundance in a countryside that was green in some bygone century. In a way Toquepala is still pristine, it is the way the engineers planned it-from the ground up. There are no additions or expansions- those tackings-on that spoil the symmetry of design while increasing the profit. This does not deny that annual production has gone up over the years. Daily mill throughput has been increased from 30,000 to 42,000 tpd. Initial design of the concentrator was for 30,000 tpd but in 1964-65 milling capacity was increased to 36,000 tpd at a cost of $3 million.

Jan 11, 1969

By B. Silliman

THESE ores occur in the Laurentian rocks in the town of Clifton, St. Lawrence County, New York. The Clifton Mining Company have opened these magnetites upon their estate of 23,000 acres, on the waters of the Grasse River, an affluent of the St. Lawrence, which flows for about nine miles across the estate, exposing a section of the formation, and affording ample water-power at numerous points. In approaching this district from De Kalb Junction, upon the Watertown and Ogdensburg Railway, the observer passes from the zone of the specular ores, which abound to a great extent in Jefferson County, across a belt of non-metal-liferous limestones, continuing for some miles intermingled with metamorphic rocks, and gradually giving place to heavy beds of granitic and porphyritic gneiss, the weathered surfaces of which present a gray and rough appearance, from the washing out of the feldspar; leaving the quartz very prominent, and completely disguising the real character of the rock, which, when freshly broken, has a lively reddish appearance from the predominance of flesh-colored and red feldspar. Beds of fine-grained quartzite appear also intercalated in the granitic gneiss. These are the dominating rocks of the magnetite region, but the magnetite is always found, so far as the speaker's observation extended, associated with beds of calcite, carrying hornblende, black and green, biotite, and brown garnet interspersed with yellow and magnetic pyrites. The strike of these rocks is about northeast, and their dip about 40° to 45° southeast.

Jan 1, 1873

By J. M. Sands

Describes important developments in, four counties, all of which brought in 40° oil. Indications are favorable for the future, although the daily production of the agate decreased 19,000 bbl. during the year 1923. THE state of Kansas had a daily average crude-oil production of about 87,000 bbl. at the beginning of the year. This showed a steady but consistent decline during the 12 months, so that the daily average production at the end of the year was slightly over 68,000 barrels. GREENWOOD COUNTY THE most active development in Kansas during the year was in Green-. wood County, in a line from near Sallyards in T 25-R 9 to east of Madison in T 22-R, 11. The main part of. this development has been in a succession of pools beginning at the south with the Polhamus pool in 34-24-9 and 3 and 4-25-9; Thrall pool in 28, 29, 32 and 33-23-10; Burkett pool in. 13, 23, 24 and 26-23-10; Seeley and Wick pool in 22, 27, 28, 32 and 33-22-11 and 5, 6, 7, and 8-23-11; Frohm pool in 11, 14 and 15-22-11; Madison pool in 31 and 32-21-12 and 6, 22, 12 and 1-22-11. Some of these pools, have two or more sands, locally called Bartlesville and Burgess Sands. They range in. depth from 1850 ft. near Madison to 2450 ft. near Sallyards, the general dip being to the west. The thickness of these sands runs from 20 to 100 ft., the initial production of the wells being 50 to 1000 bbl. of 40-gravity oil or better.

Jan 3, 1924

By H. W. Turner

The axis of the middle portion of the Ural mountains is made up chiefly of highly compressed igneous and sedimentary schists, considered of Devonian age by the Russian geologists, with large areas of serpentine (peridotite originally) gabbro, etc,, intrusive in the schist series. In addition there are large areas of probably older granitic and gneissic rocks. The nickel deposits referred to in this paper are found in the Devonian schists and their associated igneous rocks. The gabbro-peridotite intrusions probably took place in late Devonian or early Permian time, inasmueh as the Permian and Carboniferous beds lie at gentle angles on the Devonian series on the west slope of the Urals. Perhaps the first attempt to work a nickel deposit in the Urals was made about 1866 in the Revdinsk district, which is situated southwest of Ekaterinburg. 3 was informed by a Russian that a wet method of extracting the nickel was tried but was not a commercial success. This deposit has been described by Muller,l Foullon, and Karpinski.3 Beck4 gives an abstract of these papers. ; Lying to the southeast of the Revdinsk district, the Sissert estate intervening, is the Verkhne-Ufalei district, which is traversed by the railroad from Ekaterinburg to Cheliabinsk, as shown on the map, Fig. 1, there being a station on this railroad at the iron-smelting town of Verkhne-Ufalci. About 7 versts (4.6 miles) north of this town is the Nijni-Karka-dinsk iron mine, which is a limonite deposit. In one of the shafts in this mine a serpentine rock showing a green mineral was encountered. A sample of this mineral collected in 1910 was tested by Mr. Wyatt, chief chemist of the Karabash laboratory of the Kyshtim Mining Works, and determined as nickel ore. A thin section of one piece of the serpen-

Jan 1, 1915

Through the generosity of Sir Robert Hadfield, Honorary Member, the Directors of the American Institute of Mining Engineers are enabled to announce the Hadfield Research Prize of $1,000 for the best contribution to the publications of the Institute upon the general subject of The Different Forms and Combinations of Carbon with Iron, including those in Iron Alloys. The prize will be awarded at the Annual Meeting of the Institute in February, 1916, to the best paper upon this subject which is presented to the Institute before Nov. 1, 1915, provided such paper is deemed worthy by the Institute's Iron and Steel Committee. The following suggestions are also added for the guidance of those who may take part in this research. While' it is not desired to define closely the exact lines or scope of the proposed research, as it is advisable to make these as broad as possible, the object in mind maybe said to be generally as follows: To elaborate and find out the best methods of determining the forms of carbon in steel or iron, including those in iron alloys. A portion of the work would probably be a continuation of the researches which have in the past been carried out by Jullien, Abel, Muller, Ledebur, T. Sterry Hunt, Akerman, Arnold, Stead, E. D. Campbell, Hogg, Parry, Upton, and others. In a generic way, metallurgists now speak of carbides, sub-carbides, double carbides, special carbides, and other combinations. It is very desirable that these should be accurately defined and understood. It is also desirable to know whether there are other or new forms; if so, can these be separated and their characteristics obtained. It may be interesting to point out that the carbon compounds now definitely known are stated to number over 80,000. It is very probable, therefore, that there is room for much valuable and useful research to be carried out with the object of increasing our knowledge of the various combinations of carbon with iron, as probably some of these are still unknown

Jan 5, 1914

By C. E. Shoenfelt

There were 110 important discoveries of either oil or gas in Co1orado in 1935. There was, however, further development of the Price structure in southern Colorado and developments since the first of the year indicate. that an important oil field may be in the making. The discovery of oil in Price structure was made by the Oil City Petroleum Co. late ill Novem-ber, 1934, in its No. 2 Garnett in the northeast corner of lot 3 in the SW.¼ of sec. 25-33N.-2E. This well developed a good showing of oil in Dakota sand at 970 ft. The hole filled up 15 ft. with 40° gravity oil overnight and after standing for several days the oil level was 400 ft. higher. As a result of the discovery of oil by the No. 2 Garnett, three wells were drilled by the William E. Hughes Estate. Two of these wells had good showings of oil and may make good producers but it is doubtful whether they will produce the estimated capacity of 500 bbl. each with which they have been credited. Although the Hughes Estate wells have been completed for some time, they have not been given thorough production tests because of the isolated position of the field and lack of proper facilities. The. first well drilled by the Hughes Estate was located on the west side of the Navajo River on the downthrow side of a fault. It encoun-tered water ill the Dakota sand at 1285 ft, and was abandoned in green shales of the Morrison at 1405 ft. Well cuttings from the Dakota sand showed some evidence of once containing oil, so a 1ocation was selected for No. 2 Fee on the east side of the river and on the upthrow side of the fault. Oil was discovered in Dakota sands ill 1935 by Continental Oil Co. in its No. 3 Hoye, NW.NW.NE. of sec. 34-9N.-78W., on the South McCallum anticline in North Park, Jackson County, Colo., but on account of heavy flows of carbon dioxide gas under high pressure it has been impossible for the company to get an accurate gage of the oil production. The freezing action of expanding carbon dioxide makes the producing of the oil difficult and costly.

Jan 1, 1936

By C. E. Shoenfelt

There were 110 important discoveries of either oil or gas in Co1orado in 1935. There was, however, further development of the Price structure in southern Colorado and developments since the first of the year indicate. that an important oil field may be in the making. The discovery of oil in Price structure was made by the Oil City Petroleum Co. late ill Novem-ber, 1934, in its No. 2 Garnett in the northeast corner of lot 3 in the SW.¼ of sec. 25-33N.-2E. This well developed a good showing of oil in Dakota sand at 970 ft. The hole filled up 15 ft. with 40° gravity oil overnight and after standing for several days the oil level was 400 ft. higher. As a result of the discovery of oil by the No. 2 Garnett, three wells were drilled by the William E. Hughes Estate. Two of these wells had good showings of oil and may make good producers but it is doubtful whether they will produce the estimated capacity of 500 bbl. each with which they have been credited. Although the Hughes Estate wells have been completed for some time, they have not been given thorough production tests because of the isolated position of the field and lack of proper facilities. The. first well drilled by the Hughes Estate was located on the west side of the Navajo River on the downthrow side of a fault. It encoun-tered water ill the Dakota sand at 1285 ft, and was abandoned in green shales of the Morrison at 1405 ft. Well cuttings from the Dakota sand showed some evidence of once containing oil, so a 1ocation was selected for No. 2 Fee on the east side of the river and on the upthrow side of the fault. Oil was discovered in Dakota sands ill 1935 by Continental Oil Co. in its No. 3 Hoye, NW.NW.NE. of sec. 34-9N.-78W., on the South McCallum anticline in North Park, Jackson County, Colo., but on account of heavy flows of carbon dioxide gas under high pressure it has been impossible for the company to get an accurate gage of the oil production. The freezing action of expanding carbon dioxide makes the producing of the oil difficult and costly.

Jan 1, 1936

By Geo. H. Ashley

THE year 1923 saw a decline in the production of crude oil and a strong advance in the production of natural gas. The production of petroleum in Pennsylvania has been remarkably uniform for many years, but with a slight average decline. Until 1918, production was maintained above 7,500,000 bbl. Four of the six years from 1918 to 1923, inclusive, saw a yield of between 7,400,000 and 7,500,000 bbl.; 1923 gave only 7,253,000 bbl. The production of natural gas in Pennsylvania has been variable, reaching a maximum of 138,000,000,000 cu. ft. in 1906 and nearly reaching that figure again in 1907 and 1917. In 1921 production dropped to 86,000,000,000 cu. ft., and it seemed that a rapid decline had set in. Prices were raised by most of the gas companies, and -these raises sustained by the Public Service Commission. Possibly as a result of this and the better prices realized, drilling in the gas fields has been active. The year 1923 has not been prolific in large oil wells. The largest single well was drilled by the Manufacturers Light & Heat Co. on the William Auld farm near Prosperity, Morris township, Washington County. This well started at 225 bbl, but quickly dropped to 60 bbl. A 100-bbl. well was struck in September in Springhill township, Greene County. Three wells in the Tidioute pool started at 50 bbl. or better, and a well near the 28th Ward, Pittsburgh, came in at 60 bbl. One well in Washington County started at 50 bbl., but all of the other wells started at less than 20 bbl. The Tidioute pool, which was the sensation of 1922, had by Jan. 1, 1923, dropped in daily total production to 1430 bbl., by Feb. 1 to 1040 bbl., and by May 1 to 700 bbl. At that time, most of the wells were still flowing naturally, though, as the gas pressure was rapidly decreasing, it was not anticipated that such a flow would long continue. As the wells in this pool started at from 500 to. 800 bbl.. a day, it is evident how rapidly they fell off. In August, 1922, the average production per well per day was 44 bbl. ; in February, 1923, 4 bbl.

Jan 3, 1924

By Sherwin F. Kelly

Drilling in the Oligocene potash basin of Alsace prior to 1927 had shown important differences of level in the salt beds thus encountered. TO explain this a somewhat unsatisfactory hypothesis of faulting had been advanced. During the latter part of 1926 and the beginning of 1927 our firm was engaged by two organizations1 for the purpose of trying to supplement, by an electrical survey, the geological data this far collected. As a result of this exploration it was possible to affirm that salt dome structures were present in the Oligocene basin of the Upper Rhine, something heretofore absolutely unknown in that region. Two salt domes were actually outlined: one, near Meyenheim, was made the subject of a communication to the Academy of Sciences, by G. Friedel;2 the other, near Hetten-schlag, was briefly discussed by C. and M. Schlumberger3 before the same academy. The purpose of this paper is to indicate the stratigraphic and structural conditions of the area where these salt domes were found; to discuss the results of the electrical survey which led to the location of the domes; and to indicate the new geological outlookwhich such a discovery suggests. Stratigraphy In the southern part of the Rhine graben the Oligocene rests almost directly on the Middle Jurassic and consists, in ascending order, of: 1. Green marls, not salt-bearing, composed of fresh and brackish water deposits. 2. Middle stage, salt-bearing, consisting of lower-schistose marls and upper, variegated marls. 3. Blue marls, not salt-bearing, but including gypsum deposits; hence sediments laid down in a bay more or less connected with the sea.

Jan 1, 1929

By Chase Palmer, Edson S. Bastin

While the reducing action of organic matter, of ferrous sulphate, and of hydrogen sulphide has frequently been invoked to account for the deposition of native gold and silver from ore-forming solutions, the high efficiency in this respect of certain of the metallic minerals which form the ore itself has not been suffciently recognized. If a little finely powdered chalcocite is placed in a test-tube arid 2 or 3 cc. of a dilute solution of gold chloride are poured over it, two or three shakes of the tube suffice to remove all the gold from the solution. The color of the solution changes from yellow to pale green, showing that copper is dissolved simultaneously with the precipitation of metallic gold. If a piece of chalcocite is hung in a dilute aqueous solution of silver sulphate (1/40 normal), a coating of silver begins immediately to form on the mineral, and within a few moments a beautiful silver tree has developed, similar to that formed when metallic zinc is immersed in a similar solution. When similar experiments are conducted with other sulphides and with certain arsenides and sulph-arsenides, especially those known to be commonly associated with native silver in ore deposits, it is found that these minerals differ greatly in their efficiency as precipitants, especially in their effect on silver solutions. The tests made with most of the minerals were qualitatipe only, but the reactions of a silver sulphate solution on chalcocite and niccolite were submitted to quantitative study to determine the nature of the reactions involved. Quantitative studies of the reactions with other minerals are now in progress

Jan 1, 1914

By E. W. Henderson

Oil and gas development in Utah in 1936 added nothing of importance to the commercial possibilities of the state and consisted principally of efforts to reach objectives in wildcat wells started prior to 1936. Leasing activity on structures having oil and gas possibilities in beds of Pennsylvanian age or older followed announcement by the Standard Oil Company of California that a test of beds of Mississippian age would be made on the San Rafael structure. DRilling Clay Basin, Dagget County.—The Mountain Fuel Supply Co. completed a third well, sec. 16, T. 3 N., R. 24 E., on a flank of this structure. Total developed open flow of the field is approximately 50 million cubic feet and sufficient reserve has been established to warrant construction in 1937 of a pipe line connecting with the Salt Lake City-Ogden line. San Rafael, Emery County.—The Standard Oil Company of California started a wildcat test in sec. 22, T. 23 S., R. 11 E. Circulation was lost in a water-filled cavity, in dolomitic limestone, below 2185 ft. and the hole conditioned as a water supply for drilling a second test in sec. 27, T. 23 S., R. 11 E. The Carter Oil Co. in 1921 drilled a well in sec. 24, T. 23 S., R. 11 E., which was abandoned at a depth of 3035 ft. after testing at least a part of the Pennsylvanian section. Czsco, Grand County.—Drilling operations at the Utah Sout.hern Oil Company's test in sec. 33, T. 22 S., R. 22 E., continued throughout the year. Information obtained by means of a seismographic survey of the area indicated that beds of Pennsylvanian age would be found at approximately 2500 ft. The bottom of the hole at 6300 ft. is believed to be in beds of Pennsylvanian age but positive determination has not been made froin the drill cuttings. Green River, Grand County.—Test of Glen Ruby et al., sec. 34, T. 21 S., R. 16 E., was abandoned at 2627 ft. as a dry hole after drilling into Permian Kaibab limestone. Shows of oil and gas were reported and a flow of carbon dioxide gas under low pressure encountered.

Jan 1, 1937

By John T. Galey

Oil and gas development in southern Pennsylvania during 1937 was marked by considerably increased activity in deep-sand drilling. Nine tests were completed to the Oriskany sand: one in Independence and three in South Beaver townships, Beaver County; one in Franklin township, Butler County, two in Slippery Rock township, Lawrence County; one in Mt. Pleasant township, Washington County, which is drilling below the Oriskany, and one in Fairfield township, Westmoreland County. Two of these wells, both of which were in the Blackhawk pool, South Beaver township, Beaver County, obtained wet gas with open-flow volumes of 1.5 million cu. ft. and 3.1 million cu. ft. and closed-in pressures of 1900 Ib. The remaining seven were unproductive in the Oriskany. Two wells, one in Hampton township, Allegheny County, which is shut down temporarily as a result of a gas pocket, and one in South Beaver township, Beaver County, are drilling to the Oriskany. One deep test on the Chestnut Ridge anticline, South Union township, Fayette County, was completed after considerable difficulty as a dry gas well in the Onondaga limestone. At this locality the cherty limestone is porous as a result of fracturing. Three additional tests are under way in the area, one in South Union township, a second in North Union township, and a third in Wharton township. Completions Oil.—Despite price cuts and production curtailment of Pennsylvania Grade crude, caused largely by a decreasing demand from export markets, operation in the shallow oil areas continued at a fairly high rate and a number of good wells were completed. Some of these were new wells in close proximity to old production and others were old wells drilled into deeper pays. One new well of a number of producers drilled to the Nineveh Thirty-foot sand in the Harvey pool, Center township, Green County, made 400 bbl. of oil and 500 million cu ft. of gas the first 24 hr. The Chambers dam pool of Amwell and South Franklin townships, Washington County, yielded a number of Fifth Sand producers with initials as high as 200 bbl. Several wells in the old Mars-Butler field

Jan 1, 1938

By J. A. Bartnik, Gerald D. Rose, William H. Benson

New techniques in the magnetite and heavy media beneficiation industries demand more efficient magnetic dispersion and flocculation of the finely ground particles. Demagnetizing coils must produce several major effects, such as improving classification and screening efficiency, decreasing moisture content in filter cake and improving separation selectivity and green pellet properties. Likewise, magnetic flocculators must increase filtering rates and the settling rates of solids, improve magnetite recovery and produce cleaner water. To improve the design of equipment and to conduct tests leading to the optimization of such dispersion and flocculation, a program was initiated at Eriez Magnetics. The major conclusions reached are: 1. Laboratory and plant scale tests conducted on magnetite products show that a demagnetizing force of 450 rms oersteds at 60 cycles for 1/20- second duration will depolarize natural magnetite particles coarser than approximately 10 microns. This has been found satisfactory for most applications. 2. Effective flocculation of magnetite was obtained when a slurry with more than one percent magnetite was exposed for a period of approximately 1/15 second to a 600-gauss field. 3. The cost of demagnetizers (or flocculators) increases rapidly for larger diameter pipes. In order to reduce the cost, narrow rectangular sections are recommended for magnetic flocculators. 4. For minimum operating cost, permanent magnetic flocculators are ideal, chiefly because they do not require any maintenance and have no operating cost. 5. A newly designed electro-demagnetizing coil with high heat dissipation and a nonmetallic core provides high efficiency and long life. 6. To select the correct magnetic flocculator (or demagnetizing coil) the following information is necessary: a. Magnetic product susceptibility b. Magnetic product coercive force c. Percent of magnetic product d. Flow rate e. Viscosity f. Structure of magnetic product

Jan 8, 1968

By Howard I. Smith

THE mineral trona was discovered on Government land in 1938, about 18 miles west of the town of Green River, Wyo., in the core of the John Hay, Jr., well, a test well drilled for oil by the Mountain Fuel Supply Co. in sec. 2, T. 18 N., R. 11o W., sixth principal meridian. Although no oil or gas was reported, the drilling led to a discovery of great potential economic importance and exceptional scientific interest. Trona is a relatively rare mineral found at various places in playa deposits but not previously found at any great depth. It is composed of hydrous sodium carbonate and sodium bicarbonate (Na2CO3.NaHCO3.2H2O). Pure trona contains the equivalent of 70.35 per cent of sodium carbonate. Total sodium computed to carbonate times 1.42 equals the percentage of trona in the absence of other sodium carbonate minerals in the sample. ANALYSES Two short pieces of core sent to the author a few days after the completion of the Hay well were analyzed by R. C. Wells† and found to be exceptionally pure trona. A brief article on this discovery has already been published.1 Arrangements were then made through W. T. Nightengale‡ for the author to inspect and sample the core. The company log of the well included notations of sodium salt crystals from a depth of 1190 to 1820 ft. Not being able to identify all the minerals present, the author selected several specimens of the core for petrographic examinations and sampled the sections of trona for analysis. J. J. Fahey, of the Geological Survey, examined the specimens and reported most of the crystals to be a new anhydrous sodium carbonate and calcium carbonate mineral (Na2CO3.2CaCO3), which he named shortite,2 after Maxwell N. Short.* He analyzed the samples of trona, with the results shown in Table i. [ ] In addition to the 10 ft. I in. of trona in the first section, it is reasonable to assume that the 9 ft. 8 in. for which no core was available for sampling is either mostly trona or some other soluble salt, but it should not be included in calculating reserves. In the part of the core between 1590 ft. 3 in. and 1600 ft. 4 in. the material insoluble in cold water, amounting to about 5 per cent, was estimated petrographically to contain 70 per cent clay, 25 per cent shortite, and 5 per cent pyrite. ACCOMPANYING MINERALS Fahey later secured about 600 ft. of the core for a detailed examination and study

Jan 1, 1942

By Stanislaus Skowronski

THE melting of cathode copper, usually containing 99.98+ per cent. Cu, would appear to be a simple matter. Owing to the well known affinity of copper for sulphur, however, so much sulphur is absorbed by the copper during the operation that a long and expensive refining process is required to remove it, and the final product is inferior in purity and lower in electrical conductivity than the original cathode copper. The furnace operation, as now conducted, includes the following stages: 1. Charging the cathodes into the furnace. 2. Melting the cathodes. 3. Oxidizing period-saturating the copper with cuprous sub-oxide and bringing the metal to the condition known as "set copper;" this is now done by blowing air into the molten bath of metal. 4. Reduction period, otherwise known as "poling," whereby the oxygen previously added is removed by covering the molten bath completely with coke or charcoal and introducing large poles of green wood; this reduces the cuprous sub-oxide, bringing the copper to the "tough pitch" stage ready for casting. 5. Casting Period. Many experiments have been made to obviate the long periods of oxidation and subsequent reduction, with no success. While the copper first, cast will be good, as indicated by the set surface of the bars, it is impossible to hold it to the "tough pitch" condition, and long before the whole charge has been poured the copper will become "overpoled," entailing numerous difficulties. Sulphur has always been blamed by the furnace men as the reason why this refining process is necessary, yet the literature on the subject does not sufficiently emphasize how small a proportion of sulphur will ruin copper for practical purposes.

Jan 3, 1918

By S. Skowronski

The melting of cathode copper, ususally containing 95.98+ per cent. • Cu, would appear to be a simple matter. Owing to the well known affinity of copper for sulfur, however, so much sulfur is absorbed by the copper during the operation that a long and expensive refining process is required to remove it, and the final product is inferior in purity and lower in electrical conductivity than the original cathode copper. The furnace operation, as now conducted, includes the following stages: 1. Charging the cathodes into the furnace. 2. Melting the cathodes. 3. Oxidizing period—saturating the copper with cuprous sub-oxide and bringing the metal to the condition known as "set copper;'' this is now done by blowing air into the molten bath of metal. 4. Reduction period, otherwise known as "poling," whereby the oxygen previously added is removed by covering the molten bath completely with coke or charcoal and introducing large poles of green wood; this reduces the cuprous sub-oxide, bringing the copper to the "tough pitch" stage ready for casting. 5. Casting Period. Many experiments have been made to obviate the long periods of oxidation and subsequent reduction, with no success. While the copper first cast will be good, as indicated by the set surface of the bars, it is impossible to hold it to the "tough pitch" condition, and long before the whole charge has been poured the copper will become "overpoled," entailing numerous difficulties. Sulfur has always been blamed by the furnace men as the reason why this refining process is necessary, yet the literature on the subject does not sufficiently emphasize how small a proportion of sulfur will ruin copper for practical purposes. The sulfur absorbed by copper during the melting period comes from two sources: (1) the sulfate left on the cathode sheets in the tank houses; (2) the fuel. The percentage of sulfates on the cathodes is variable, and depends on the care taken in washing the cathodes after removing

Jan 1, 1919

By Julien F. Phillips, Donald E. Garrett

The production of soda ash from natural sources is one of the United States' oldest industries. The London Company, which financed the settlement of Jamestown, in the fall of 1608 exported in its first cargo from Virginia " . . . trials of pitch, tar, glass, frankincense, and soap-ashes."1 This last product, a crude mixture of sodium and potassium carbonates obtained by the burning of wood in iron pots, was the commercial soda ash of its day, used in the infant soap, glass, and bleaching industries. Besides having a good cash value, its production helped to clear the land, and it was a compact, easily shipped commodity. The extra high potassium content of these American "pot-ashes" gave them an added market as a fertilizer, a field that they dominated until the opening of the Strassfurt deposits in 1860. This form of natural soda ash disappeared forever from commercial importance with the introduction of the Le Blanc process (1791), and later the Solvay process for manufacturing soda ash. The Solvay process was rapidly accepted in the United States, and has accounted for most of the country's soda ash production since 1884. It was not until the western part of the country began to be developed that natural soda ash was again produced. A number of lakes, playas, and springs west of the Rocky Mountains were found to be rich in this mineral, and climatic conditions were ideal for its easy recovery by solar evaporation. The production of natural soda ash from these deposits has become a steadily growing industry in the United States. Production A summary of the production and value of natural sodium carbonates in the United States is presented in Table 1. Prior to 1927 the principal output came from several different companies at Owens Lake, California. Then production at Searles Lake, California, began to [ ] increase until it became the most important source. In 1948 the sale of crude trona from Green River, Wyoming, commenced and since that time production from these latter two areas has been about equal. Table 2 lists the four

Jan 1, 1960