Crystallising House and Evaporator Buildings of American Potash and Chemical Corporation
GEORGE R. MANSFIELD U. S. Geological Survey, Washington, D. C.
The war finds the United States equipped with a potash industry well established with adequate supplies of raw materials, good methods of production, ample plant capacities, and prices little affected by the disturbed conditions of world trade. Reserves may be grouped in three classes: (a) soluble-potash salts and brines now in active production-the sylvite and langbeinite beds mined in New Mexico and the brines of Searles Lake, Calif., and of the Salduro area in the Great Salt Lake Desert, Utah; (b) carnallite and alunite beds in Utah under investigation for operation with mag-
HE story of American potash has been told so often that only enough of it need be reviewed here to provide a setting for the brief discussion of potash reserves which is to follow. I n 1914 a t the outbreak of the First World War, Germany was virtually the sole source of supply for the potash needs of the world. The United States, having learned through an unfortunate experience some of the disadvantages of dependence on Germany, was already bestirring herself to find supplies of her own but had made little progress before war conditions shut off foreign supplies. The dearth of potash and the skyrocketing of prices added impetus to the search, and many expedients with both inorganic and organic source materials were tried, mostly without lasting success. After the war research was continued chiefly along two lines. The Govern-
nesium or aluminum as the principal product but with potash as a coproduct; (c) mineral supplies abundant enough for large-scale production but subject to technological advances, development of marketable coproducts, eto.-polyhalite, leucite, greensand, and others. The available quantities of materials of the third class are enormous, and by the time supplies of the first two classes are exhausted, conditions may be ripe for their exploitation. In any event, the potash industry in America is more likely to be affected by world conditions after the war than by any lack of raw materials.
ment followed up oil-well drilling in the Permian Basin of Texas and New Mexico to find evidences of potash beds of possible commercial importance that might have been cut by the drills, and the American Trona Corporation a t Searles Lake, Calif., predecessor of the present American Potash and Chemical Corporation, applied itself assiduously to problems of chemical research and engineering to separate potassium chloride commercially from a complex natural brine. Both agencies accomplished their objectives. The American Trona Corporation, though active as early as 1916, entered upon continuous production in April, 1922 (97); the Government with a wide field to cover and with methods that were necessarily indirect did not find sylvite in the Permian Basin until 1925. Since that time matters have moved more rapidly. The 1417
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American Potash and Chemical Corporation has enlarged its plant and broadened its basis of operations to include a wider variety of products than the potassium chloride and borax with which it started. Before Congressional authorization could be obtained for core drilling in the Permian Basin by government agencies, private interesk in 1926 had begun the first core test for potash in that area. Government agencies followed early in 1927. Areas found by drilling t o contain sylvite were leased by the Government to three different companies, all of which are mining sylvite, and in addition one is mining langbeinite (K2S04.2MgS04). Some of this product is sold without refining, but part is treated with sylvite to make potassium sulfate and magnesium chloride. The magnesium chloride is to be recovered a t the mine and shipped to a plant now under construction for the production of magnesium.
The Present Situation The second World War finds the United States equipped with a potash industry well established with adequate supplies of raw materials, methods of production carefully worked out, plant capacities ample for expected domestic and export demands, and prices little affectedby the disturbed conditions of world trade. The future of the potash industry in the United States is subject to two broad controls. The first is natural, concerned with sources of supply; the second, political and social. So far as can now be predicted, the industry is secure for a t least several generations and probably indefinitely. The available raw materials determine the nature of the necessary operations and, to some extent, the prices a t which the American potash industry may undertake them. Thus they exercise a natural control over the industry. Although organic sources of potash were drawn upon during the first World War and are represented today by molasses distillery waste, which is still productive in a small way, the present discussion is concerned with inorganic sources which alone can be counted upon to give continuous large-scale production.
First-Order Reserves In the category of first-order reserves are placed the sources now productive. They include potash salts, minable as such, potash-bearing brines, and cement materials Potash salts minable under present commercial conditions are now available only in Eddy County, iY.Mex., which is part of the great Permian Basin that extends northeastward from west Texas to central Kansas. Brines now under exploitation for potash include only those of Searles Lake, San Bernardino County, Calif., and those in the west-central part of the Great Salt Lake Desert, Tooele County, Utah. Some cement plants are located sufficiently near sources of potashbearing silicates to use such materials in their mix and to recover the volatilized potash from flue dusts. Several cement companies did this during the first Vorld War, but only one is doing it today. NEW MEXICO. The area in which the principal potash minerals-sylvite, carnallite, and langbeinite-have been found comprises about 3000 square miles chiefly in Eddy and Lea Counties, New Mexico, but extending also into Loving and Winkler counties, Tex. (13). Within this larger area a smaller area of about 100 square miles has been prospected more intensively by private and government core tests. This smaller area constitutes the New Mexico potash field (24, 26). Carnallite has also been reported from two wells in southwestern Midland County, Tex. (ZZ), but core recoveries from these wells were poor and no further exploration for potash has been undertaken there. In the New Mexico
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potash field the reserves in 33 square miles have been studied in more detail by Smith (2.4, 66) who has distinguished by number forty beds that are potash bearing. He estimated that the beds with a minimum content of 14 per cent KzO (the average content of the German salts) and more than 4 feet thick in this area of 33 square miles contain 100,000,000 short tons of potash salts. One fourth of these salts he estimated to contain more than 28 per cent of potash and thus to have twice the average richness of the salts mined in Germany. If the basis of the estimate were lowered to include material containing 9 per cent of KzO equivalent, the estimate could be enormously increased for the sylvite zone in shaft No. 1 of the United States Potash Company, which comprises many beds, contains one section 82 feet thick and another 58 feet thick, or a total of 140 feet of beds that average about 9 per cent KzO (16). Although Smith has made no further formal estimates of reserves of potash in New Mexico since 1933 (24),his official duties as head of the Mining Division of the Conservation Branch of the Geological Survey have kept him in close touch with new drilling and mining developments in that field. He now estimates (26) that 75,000,000 short tons of K,O would be a conservative figure, and this figure supplied by him is used by Thorp and Tupper (28) in their report on the potash industry in 1940. SEARLES LAKE,CaLIF. As described by Gale (8),Searles Lake is the greatly reduced modern representative of a much larger lake which in Pleistocene time was a member of a chain of lakes, occupying neighboring valleys in the general area between the Sierra Nevada Mountains and the region east of Death Valley. It is now only a depression in the bottom of which lies a salt mass occupying an area of 11 or 12 square miles. According to Teeple ( d 7 ) , the salt body covers this whole area t o a depth of 50-75 feet, and below this is mud for over 500 feet. The salt mass is still saturated with the mother liquor. The potash and other coproducts are made from brines pumped from wells drilled in the salt area and processed in a plant that marks a triumph in research and chemical engineering. In the first government announcement (8, pages 309-10) regarding the lake, its potash content was estimated as between 4 and 10 million short tons of KzO. A company engineer ($0)a few years later estimated the potash content of Searles Lake brine a t 23,760,000 tons of KC1 (equivalent to 14,850,000 tons KzO). The latest Geological Survey figures (9) published in 1919 gave the potash content as 20,000,000 tons of KzO. Meanwhile the lake has been in active production a t an accelerating rate for over twenty years. Thorp and Tupper (29) have recently estimated reserves of potash a t Searles Lake as 10-12 million short tons of K20. GREATSALTLAKEDESERT. Separated from Great Salt Lake and west and southwest from it lies the Great Salt Lake Desert which occupies most of western Tooele County, Utah, and extends northward and southward into Boxelder and Juab Counties. This great mud flat, once covered by the Pleistocene Lake Bonneville, has two depressions occupied by bodies of crystalline salt; the larger, known as Salduro Marsh, has an area of about 125 square miles. Salduro station of the Western Pacific Railroad is in the midst of this salt area (6, 6 ) . The maximum thickness of the salt body is about 5 feet. Surrounding and underlying the salt are muds whose thickness is unknown but is estimated a t about 1000 feet (28). The salt mass itself contains very little potash, but the brines that saturate the salt and some a t least of the underlying muds contain noteworthy amounts. An analysis cited by Gale (6) gave 3.69 per cent K, equivalent to 7.03 KC1 in the dissolved salts. The other dissolved salts are chiefly sodium chloride 81.04 per cent and magnesium chloride 9.07
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(6); calcium and sodium sulfates are low (0.88 and 1.98 per cent, respectively) The general simplicity of this brine and its resemblance to the artificial brines of the German potash works (7) make it adaptable to processing by solar evaporation. From 1917 to 1921 potash was produced at Salduro marsh first by the Solvay Process Company and later by its subsidiary the Utah Salduro Company, and in 1920 this company was the largest individual producer of potash in the United States (1’7,page 27). Since 1921 interest in Salduro as a source of potash has been kept alive largely through the efforts of the late 5. L. Silsbee, formerly manager of the Salduro plant, who described the area and outlined the solar evaporation method of producing potash there (23). I n 1938 Bonneville, Ltd., resumed production of potash from this area (10) and has continued with increased production (11). The earlier accounts (6, ‘7, 23) gave the impression that large quantities of brine were available for potash production in the Salduro area. However, Nolan’s work (17, page 43) indicates that the shallow brines are likely to be rapidly exhausted, and that large-scale operations will require for their maintenance the development of the deeper brines, concerning which little is now known, SUMMARY.At the present annual rate of consumption500,000 tons of KzO (26)-first-order reserves of potash, including all three sources described, could probably supply the country’s needs for about two hundred years. I
Second-Order Reserves
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of which 10,324,600 tons are alunite; but he estimates that only 1,361,000 tons of the total alunitized rock contains 50 per cent or more of alunite. Thoenen (68) gives somewhat larger figures for similar estimates. At present, detailed investigations carried on jointly by the GeoSurvey and the Bureau of Mines are in progress s area. If the entire estimated amount of alunitized rock were considered to average 8 per cent KzO, the available reserves of potash in the district would amount to somewhat less than 3,000,000 tons. If only the rock estimated to contain 50 per cent or more of alunite is taken and its average KzO content considered as 8 per cent, the total KzO available would amount to only 106,880 tons. The actual amount may be less, but closer figures must await the completion of the detailed investigation now in progress. CARNALLITE IN UTAH. Several wells drilled for oil in the Salt Valley anticlinal area have yielded indications of the presence of potash salts. Although polyhalite and sylvite have been recognized in the cuttings from some of these wells and were found in the twenty-fourth government core test drilled there for potash (IS), carnallite (KC1.MgClz.6HaO) appears from present evidence t o be the most abundant potash salt present in the area. First recognized in the Crescent Eagle well (12)near Thompsons, Utah, it has since been found in at least five other wells. Although the available information is insufficient for the estimation of reserves of potash in the Salt Valley area, it is evident that they are potentially large. Carnallite is itself a potential source of magnesium and is accompanied in some of these wells by magnesium-bearing brines. The Geological Survey and Bureau of Mines are now conducting a deep core test as part of an investigation of the available resources of magnesium chloride in that area. If production of magnesium chloride on a large scale is undertaken as a result of this investigation, it is assumed that potassium chloride will be produced as a coproduct with magnesium chloride. Any such production would serve to extend the life of the other reserves already discussed.
I n the second-order reserves may be grouped those deposits which give promise of early development in connection with plans now under consideration for the production of aluminum and magnesium. These are concerned with alunite deposits, chiefly in the Marysvale district, Utah, and with carnallite and its associated brines and salts in the Salt Valley anticline, Grand County, Utah. I n both areas the Government is financing explorations that may lead to the early production of these metals. ALUNITE. Although alunite deposits are known in AriThird-Order Reserves zona, California, Colorado, Nevada, Texas, Utah, and Washington, those in the Marysvale district in Piute County, The list of third-order reserves is fairly long and includes Utah, which were operated for potash in the period 1915-21 polyhalite, leucite, greensand, sericite, feldspar, and others. (18,19), are probably the only ones from which any significant The development of any of these as a source of potash is amount of by-product potash may be expected. dependent on the utilization of one or more other products According to from the raw Dana (4),alunite materialselected. (K90.3A190a.It is difficult to 4S 3 . 6 H-2-0 ) forecast which of t h e o r e t ically these materials may contain 11.4 will receive atper cent KzO, tention first, or but analyses of how long it may three channel be before desamples and one velopment will carload sample begin. The war of the better effort may lead grade material to some unexfrom the Maryspected demand vale district conwhich would retained between quire t h e use 7.67 and 9.78 per of one or more cent of KzO (1). of these subR e s e r v e s of stances, or alunitized rock in some new the Marysvale unforeseen indistrict were estidustrial need Plant of the Potash Company of America mated by Callamay arise which one ghan (2) to total 36,921,000 tons, of them could
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Heavy E q u i p m e n t f o r R e m o v i n g P o t a s h Salts f r o m Large S t o c k Piles in Storage, A m e r i c a n P o t a s h a n d Chemical C o r p o r a t i o n ~-
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supply. Polyhalite or perhaps leucite would seem a t present to have the best chance. Polyhalite contains two constituents of present industrial importance, potash and magnesium, and leucite has potash and alumina. Greensand has four ingredients of possible commercial use, potash, alumina, iron oxides, and silica, but its content of potash and alumina is lower than that of polyhalite or leucite, and the utilization of the iron oxides and silica is problematical. Sericite and feldspar both have fairly high contents of potash and alumina, but the nature and mode of occurrence of these materials and the industrial problems involved in their utilization would seem to make them less adaptable to early development than the others named. Additional sources include scattered groups of alkali lakes such as those of Nebraska and Texas, from which small amounts of potash could be produced a t relatively high cost. Of the sources mentioned, all save polyhalite were utilized to some extent during the first World War and abandoned at its close. Polyhalite, leucite, and greensand deserve brief further discussion. POLYHALITE. The composition of polyhalite is: K2S04.MgS04.2CaSOa.2H20 or K,O, 15.6 per cent; RfgO, 6.6; CaO, 18.6; SO*, 53.2; HzO, 6.0. It is the most abundant and most widely distributed potash mineral in the Permian
Basin and has been recognized in wells in the Salt Valley anticline in Utah. I n the Permian Basin it has been recognized in the cuttings of many wells in western Texas and southeastern New Mexico in a general area approximating 40,000 square miles (15) and has been reported in well cuttings from central Kansas. It occurs in beds of minable thickness and depth at a number of localities in New Mexico and Texas. It could be recovered from existing mines in New Mexico if wanted. Considerable work has been done on polyhalite with the idea of obtaining potassium sulfate and so-called sulfate of potash-magnejia as marketable fertilizer products (3,31,33). Thus far the costs of production and marketing as worked out on a laboratory scale have not been sufficiently attractive to induce commercial operation. One might suppose that with the rapidly expanding needs of the country for magnesium some use could be made of polyhalite that would involve producing both potash and metallic magnesium. However, the magnesium content of polyhalite, though comparable to that of some brines now utilized, is only about one third that of langbeinite, a potassium-magnesium sulfate mineral produced in New Mexico, nom- used for potash production and soon to be used for magnesium extraction. Moreover the magnesium sulfate
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in polyhalite would have to be converted into magnesium chloride before magnesium could be produced from it, if present practice is to be followed. LEUCITE. The potash-bearing rocks of the Leucite Hills, Sweetwater County, Wyo., have been estimated to contain nearly 200,000,000 tons each of potash and alumina, which average about 10 per cent of the rock masses of which the hills are composed (21). Although attempts were made during the first World War to obtain potash from this souroe, the laboratory process which had promised success broke down when production on a commercial scale was attempted, and little, if any, potash was actually produced. Since that time elaborate schemes have appeared now and then for utilizing these leucite-bearing rocks in connection with nearby phosphate, coal, limestone, and sodium carbonate, together with more distant sulfur as the basis of a large industry to produce fertilizers and a variety of chemicals. The latest of these proposals was made in Washington in July, 1941, before a Senate committee (82). I n view of the interest now being displayed in government circles in what have hitherto been regarded as submarginal mineral deposits in western states, it is possible that some attempt will be made to utilize this source of potash. GREENSAND.The mineral glauconite, the chief constituent of greensand, is mainly a hydrous silicate of iron and potassium, but also contains considerable alumina and much smaller amounts of a number of other substances. Greensand is widely distributed in some of the Coastal Plain formations from New Jersey to the Gulf, and also occurs in older rocks here and there in the interior of the country. The richest beds are those of New Jersey and Delaware, which because of their ease of mining (open-pit methods), proximity to industrial centers, and both rail and water transportation attracted considerable interest during World War I as a possible source of commercial potash. Their potash content has been conservatively estimated at nearly 257,000,000short tons of KzO (14); however, potash constitutes only about 6.6 per cent of the principal beds whereas silica is around 50 per cent. Iron oxide (FegOa) in the same beds is about 17 or 18 per cent, and alumina ranges from 2 to 8 per cent. The silica, which can be readily separated as porous grains, has possibilities for use in filtration or perhaps insulation but thus far has not found a market. If it could be advantageously disposed of, the potash, alumina, and iron oxide could perhaps also be utilized. Turrentine, who participated in problems of greensand utilization, has summarized the experimental work on this material (SO). Greensand enjoyed some local popularity as a fertilizer for many years before prepared fertilizers came on the market. Of late its principal use has been in water-softening preparations.
Political and Social Controls This subject lies outside the field of the geologist, but it requires no prophet to foresee some of the difficulties bound to arise after victory is achieved. If postwar international policies are shaped to foster friendship and cooperation among nations rather than to breed new hatreds, national life in America will be affected in many ways. Greater freedom of trade and fewer restrictions would seem to be necessary to affect the wider distribution of food supplies, clothing, and industrial raw materials implied by the terms of the Atlantic Charter and subsequent pronouncements of the Allied Nations. This may mean the reduction or abolition of tariffs and the introduction of free trade. How would this situation affect the American potash industry? Whether fortunately or not for the industry, Congress has consistently refused to apply protective tariffs to fertilizer materials needed by the American farmer. Thus
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imported potash used for fertilizer has long been on the free list. I n order to survive and grow, the industry from the first has had to meet competition with foreign potash. Incidentally, too, the potash industry both on its own account and through its connection with the fertilizer industry in general has been under popular fire for years on charges that its prices have been too high, this in the face of statistical evidence published by the National Fertilizer Association from data supplied by the Department of Agriculture and other sources that fertilizer prices are lower than those of many other things the farmer must buy. Having been thus geared to price-reducing requirements, the industry would seem to be in a sound position to meet impending changes of a social or political nature unless they become unforeseeably disturbing.
Acknowledgment The writer is indebted to R. C. Wells and H. I. Smith, of the Geological Survey, for reading the manuscript and making helpful comments and criticisms.
Literature Cited Callaghan, E., U. S. Geol. Survey, Bull. 886-D,114 (1938). Callaghan, E., unpublished data, 1941. Cunningham, W. A.,Univ. Texas, Bull. 3401, Pt. 11, 833-67 (1934). Dana, E. S., “A System of Mineralogy”, 6th ed., p. 974 (1914). Gale, H.S., Em. Mining J., 102, 780-2 (Oct., 1916). Gale, H . S., Mineral Resources of the U. S., 1916, Pt. 11, pp. 98-100, U. S. Geol. Survey, 1917. Ibid., 1917, Pt. 11, p. 413 (1919). Gale, H. S., U. 8. Geol. Survey, Bull. 580, 252 (map), 272, 273, 309-11 (1915). Gale, H. S., and Hicks, W. B., Mineral Resouroes OF the U.S., 1917,Pt. XI, p. 411,U. 8. Geol. Survey, 1919. Hedges, J. H., Minerals Yearbook, Review of 1938, Advance Chapter on Potash, p. 6, U. 9. Bur. Mines, 1939. Ibid., Review of 1939,Advance Chapter on Potash, p. 3 (1940). Lang, W. B., U. S. Geol. Survey, Bull. 785,38,39 (1926). Mansfield, G. R., last three Govt. tests find potash, Geol. Survey, mimeographed memo. for press, May 9, 1932. Mansfield, G. R., U. S. Geol. Survey, Bull. 727, 106-35 (1922). Mansfield, G. R., and Iiang, W. B., Am. Inst. Mining Met. Engrs., Tech. Pub. 212, 4 (1929). Mansfield, G. R., and Lang, W. B., Univ. Texas, Bull. 3401, 673 (1935). Nolan, T. B., U. S. Geol. Survey, Bull. 795-B (1927). Nourse, M. R., Mineral Resources of the U. S., 1920, Pt. 11, p. 105, U. 8. Geol. Survey, 1921. Phalen, W. C., ZbicE., 1915,Pt. 11, p. 110 (1916). Ropp, Alfred de, Jr., J. IND. ENQ. CHHIPI., 10, 803 (1918); Chem. & Met. Eng., 19, 426 (1918). Schultz, A. R., and Cross, Whitman, U. S. Geol. Survey, Bull. 512,35 (1912). (22) Sellards, E. H.,and Schooh, E. P., Univ. Texas, Bull. 2801, 169-201 (1928). (23) Silsbee, J. L.,Mining and Met., 6 , 425-9 (1925). (24) Smith, H.I., Am. Inst. Mining Met. Engrs., Contrib. 52, 6, 7 f1933). (25) Ib& 84 H,6 , 7 (1935). (26) Smith, H. I., personal communication. (27) Teeple, J. E.,“Industrial Development of Searles Lake Brines”, A. C. S. Monograph 49,pp. 12-14,24 (1929). (28) Thoenen, J. R,, U. 8. Bur. Mines, Rept. Investigation 3561 (1941). (29) Thorp, W. L., and Tupper, E. A., “Potash Industry”, rept. submitted to Dept. of Justice by Dept. of Commerce, p. 6 (May 1, 1940). (30) Turrentine, J. W., “Potash”, pp. 100-14,New York, John Wiley & Sons. 1926. (31) U. S. Bur. of Mines, Rept. Znwsstigations, 3002, 3032 (1930); 3061,3062,3116 (1931); 3167 (1932); 3210 (1933). (32) U. S. Senate, Hearings before Subcom. of Committee on Publin Lands and Surveys, 75th Congr., pursuant to Sen. Res. 53. Pt. 1, pp. 106-12, Washington, Govt. Printing Office, 1942. (33) Wroth, J. S., U. 8. Bur. Mines, Bull. 316 (1930) PRESENT~DD as part of the Symposium on Potash before the Division of Fertilizer Chemistry at the 104th Meeting of the A M ~ R I C ACKBMICAL N SOCIETY. Buffalo, N. Y.
