HUNT INTENSIFIED FOR MORE SULFUR
A\ t
New York Times
SULFUR DEMAND SN '51 TO TOP SUPPLY BY FAR
STAFF
REPORT
SULFUR
Wall Street Journal
WORLD SULFUR SHORTAGE NEARS CRITICAL STAGE Journal of Commerce
RAW MATERIALS GREATEST PROBLEM BUT U. S. HELPFUL; SULFUR POSITION GRAVE London Evening News
U ^ L I X J M does a week go by without sulfur touching off a blaze of n e w s p a p e r head lines. Without doubt, sulfur—the subject of earnest deliberations, endless confer ences, and hold new programs—is the chemical industry's supply problem num ber one. T h e scarcity reaches out into every sector of American industry. Its effects are global. As one raw materials expert commented tersely: "Sulfur is t h e hottest subject on the calendar." The U. S. chemical industry, which for years has been burning sulfur at a tre mendous rate, has taken it entirely for granted that sultur would come roaring out of Texas and Louisiana forever. Xuw, the cruel awakening. Predictions arc that U. S. native sullur deposits will be exhausted within 25 years. Karl) this month, the sulfur committee o! the International Materials Conference estimated the 1951 world sulfur shortage to he at least one million tons, or ahout 2()f'f of U. S. production. Because thereis little immediate prospect of any sig nificant increase in the U. S. sulfur supply, most consumers will have to face t h e fact that, for the time being, about all they can do is tighten their belts a n d hope lor the best. Canadian pulp and paper manulacturers. consuming at present about 80 r/ r of Can ada's sulfur imports (almost all of which come from the United S t a t e s ) , have been saying that unless the industry gets more sulfur, the production of newsprint is cer tain to nosedive. In mid-April, James M. Quinn, president of t h e California Fer tilizer Association, wired officials of t h e National Production Authority that, as a 2126
result oi the diversion ut suit uric a c i d to the nation's oil companies, t h e amount of acid now available for producing super phosphate and ammonium sulfate is "critically short of amount needed t o meet minimum California and Arizona d e m a n d s . A d d e d demand caused by shortage of agri cultural fertilizer materials results in des perately serious situation f o r growers." At Houston, Tex., t h e sulfuric acid short age forced Phillips Chemical Co. t o cut its ammonium sulfate? production by 35'.''. Said Jefferson D. Stewart, executive vice president of Federal Chemical Co.: "Be cause of the superphosphate s h o r t a g e I caused by the scarcity of sulfuric acid], we have laid off night c r e w s altogether. At times, some of our p l a n t s have? been completely idle." Last fall, Texas Gulf S u l p h u r r e d u c e d its domestic s h i p m e n t s to SO'/r of its cus tomers* maximum contract r e q u i r e m e n t s . On J a n . 1, 1951, Freeport Sulphur b e g a n allocating its sulfur on tHe basis of 857Ό of the 12-month baso period ending Sept. 10, 1950. T h e cuts announced b y both Texas Gulf a n d Fre s of the Gulf Coast salt d o m e s . U. S. sulfur c a m e principally from pyritic ores. Pyrites ( t h e all-inclu sive n a m e for metal sulfide minerals con taining 25 to 5 0 ' 'r sulfur) w e r e roasted to form sulfur dioxide', which, in turn, was converted to sulfuric acid. Pyrites, al t h o u g h merely a fringe source of sulfur in this country today, are still the chief sulfur source for most of t h e rest of the world. In 1867, prospectors searching for new petroleum reserves accidentally stumbled upon sulfur near Lake Charles, La. Be n e a t h the marsh, muck, quicksand, and rock, they found sulfur of extraordinary purity. T h e big problem was getting t h e sulfur out of t h e ground. Several com panies tackled t h e job headlong by using s t a n d a r d mining techniques. T i m e and again, their efforts ended in failure. T h e n H e r m a n Frasch came up with the idea that sulfur m i g h t be mined successfully by melting t h e element u n d e r g r o u n d with hot water. Although h e filed a patent ap plication for t h e process as far back as 1890, F r a s c h h a d to wait over 15 years— a period m a r k e d by r e p e a t e d setbacks— before h e could pronounce t h e v e n t u r e a success. T h e establishment of t h e Union Sul p h u r C o . by Frasch in 1896 was followed b y t h e formation of the Freeport Sul p h u r C o . in 1912, the Texas Gulf Sulphur V O L U M E
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States might t o d a y have h a d a genuinely diversified sulfur industry. Instead, t h e industry p l a c e d practically all its chips o n Gulf Coast sulfur. O t h e r sulfur sources w e r e largely neglected. However, n o w t h a t it has b e c o m e more t h a n obvious t h a t Gulf Coast production cannot k e e p p a c e with d e m a n d , the chemical industry is being forced t o look elsewhere. T h e U. S. has six basic alternatives: pyrites, hydrogen sulfide (from natural a n d refinery g a s e s ) , smelter gases, calcium sulfate, coal, and low-grade sulfur d e posits. Ironically, the most costly sources of sulfur (as far as recovery is c o n c e r n e d ) are not only t h e most plentiful but also t h e most widely distributed; they are cal cium sulfate a n d coal. In 1950, t h e U . S. o b t a i n e d 9.09' of its sulfur from pyrites, 2.4 r r from hydrogen sulfide, a n d 4 . 0 % from smelter gases. T h e remaining 8 4 . 6 % was Gulf Coast sidfur. Because of their high cost, alternatives tor Frasch sulfur are at present very m u c h in the background. However, as U. S. reserves steadily decline, the price of ele mental sulfur will inevitably rise. Simul taneously, the* production of sulfur from what currently are r e g a r d e d as marginal source's will become ever more' attractive. As William L. Swager of B'attelle Memorial institute observed: "At present, it appears that an> increase in the supply of sulfur will have to e-oine from by-product sources. . . . There is plenty of sidfur available, but not at the price that is currently b e i n g paid for brimstone. T h e economic driv ing force indicated by t h e estimated de m a n d for sulfur in I 9 6 0 will gradually bring to the market increasing quantities of by-product sulfur at increasing prices. . . . T h e r e a p p e a r s to b e no long-term sidfur shortage nor any revolution in the industry that will h a v e severe repercus-
PRODUCTION OF CRUDE SULFUR EXPORTS OF CRUDE SULFUR STOCKS AT SULFUR M I N E S , DEC. 31
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M A Y
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1951
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From Freeport Sulphur Co.'s booklet. The Magic Mineral.** Equipment not d r a w n to scale.
Sulfur discharged into sump before weighing
I* :' £
UNCONSOLIDATED FORMATION
BARREN ANHYDRITE
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sions. It will be a gradual struggle be tween the suppliers and the consumers in the marketplace." Sulfur from Pyrites Pyrites are the chemical industry's most compelling alternative to Gulf Coast sul fur. However, at brimstone's present price, the production of sulfur from pyrites is a comparatively costly proposition. In fact, when a manufacturer decides to build a pyrites-burning sulfuric acid plant, he must resign himself to paying more than twice what it would cost him to build a comparable sulfur-burning installation. However, calculations are that the pro duction of sulfur from pyrites will suc cessfully compete with Frasch sulfur when the price of brimstone at the mine rises to at least $30 a ton. Within recent years, the use of pyrites as a sulfur source has been limited largely to those plants which, because of their ideal location, are favored by low shipping costs and special market and raw mate rial advantages. T h e major share of U. S. pyrites production centers around Tennes see, although suitable ores also occur in eight other states. Estimated U. S. sulfur reserves in the form of pyrites: 76 million tons. Flash roasting is by far the most widely used method of recovering sulfur dioxide from pyrites. Recently, the Dorr Co. adapted its FluoSolids system (originally developed for the calcining of gold ores ) to the recovery of sulfur dioxide from pyrites. In t h e FluoSolids system, 3 5 - to 200-mesh sulfide particles are partially suspended in an upward-moving stream of air. T h e fluidization of the solids ensures the complete combustion of t h e particles to sulfur dioxide, which may then b e con verted to sulfuric acid. Sulfur from Natural a n d Refinery Gases T h e recovery of sulfur from the nation's oil fields, gas fields, and petroleum refin eries can b e justified on several grounds: a valuable resource becomes a source of additional income; the sulfuric acid sub sequently produced stimulates the growth C H E M I C A L
of other industries in the same area; and besides, the operator is assured that his effluent gases won't play havoc with the surrounding countryside. Oftentimes, the removal of foul-smelling hydrogen sulfide from natural gas isn't just a nice, possibh lucrative*, gesture: it's a downright neces sity. N o t only is hydrogen sulfide highly poisonous (at least five times as toxic as carbon monoxide ) but it is also exceed ingly corrosive and may lead to disastrous product contamination and costly catalyst poisoning. These factors, plus the ur gency of tlu· sulfur shortage, have spurred many companies into taking long, discern ing looks at their sulfurous plant gases. T h e most common method of obtain ing sulfur from natural or refinery gases starts with t h e recovery of hydrogen sul fide by the Girbotol process. Hydrogen sulfide is absorbed by an ethanolamine solution and then stripped from the ab sorbent by heating. Next, the isolated h> drogen sulfide is partially burned to sulfur dioxide. In a special catalyst chamber, the gases a r e converted to elemental sulfur and water. Because not very many natural gas sources contain sufficient concentrations of hydrogen sulfide, the usefulness of this technique has its distinct limitations. In the W e s t , however, the recovery of hy drogen sulfide from sour natural gas is particularly appealing, not only because of t h e high sulfur content of the gas but because there are enough» superphosphate plants a r o u n d to provide a ready and sus tained market for sulfuric acid. At present. Texas Oulf is recovering 100,000 tons of sulfur a year from sour natural gas at W o r l a n d , W y o . At McKamie and Mace donia, Ark., Mathieson Chemical is sal vaging 53,000 tons of sulfur a year from Arkansas sour gas. Hancock Chemical re covers sulfur at a rate of 25,000 tons a year from oil refinery gases in the Los Angeles area, while Freeport Sulphur re claims 4500 tons of sulfur a year from the refinery* gases that pass through its plant n e a r Westville, N . J. Said W. C . Huffman of the Petroleum Administration for Defense: "Refiners A N D
ENGINEERING
NEWS
Sulfur storage vats at the G r a n d e Ecaille mine
Molten sulfur b e i n g distributed to build-up vat have periodically reviewed the economics of sulfur recovery from their operations . . . In the past, it has ordinarily not been economic, w h a t with the low price of sulfur and its ready availability. That situation has shifted, and a n u m b e r of refiners are finding that it is not only necessary to institute means of recovering sulfur from their operations in order to have acid at all, but it is economically attractive under the present situation . . . T h e difficulty is that the equipment required for the process will take time to construct and put into operation. Although there may he spot situations where something can he done quickly to expand existing recovery, any major contribution from petroleum operation seems to be some distance off." Sulfur from Smelter Gases Each year, tremendous quantities of sulfur dioxide are evolved in the smelting of nonferrous sulfide ores. Annually, in the United States a n d Canada, a total of about 1 million long tons of sulfur are potentially recoverable from the smelting of zinc ores, 750,000 long tons from nickel ores, and 3.5 million long tons from copper refineries. W h a t with the rising price of sulfur and the crippling scarcity, the need for the recovery of sulfur from such sources has taken on a n e w dimension. In 1949, the equivalent of only about 296,000 long tons of sulfur was obtained as sulfuric acid from smelters in the United States and Canada. Sulfur from Calcium Sulfate Although sulfur is widely distributed in nature as calcium sulfate, the cost of recovering sulfur from this source is ordinarily prohibitive. Currently, TVA is exploring the production of sulfuric acid from calcium sulfate, either in the form of natural gypsum or as a chemical byproduct, particularly from the "wet process" manufacture of phosphoric acid. At Merseyside, the British are building an installation to produce 150,000 tons of sulfuric acid a year from anhydrous calcium sulfate. The n e w installation, costVOLUMF.
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ing between $9.8 and $11.2 million, will be patterned after the 100,000-ton sulfuric-from-anhydrite unit that ICI built at Billingham in the early 19*30's. Sulfur from Coal T h e hydrogen sulfide now being evolved in U. S. coal carbonization plants could add about 200,000 tons annually to the nation's sulfur supply. In turn, this sulfur could be converted to sulfuric acid for use in transforming by-product ammonia into ammonium sulfate fertilizer. In fact, the sulfuric acid obtainable in this fashion could meet about 60r/c of the coke industry's acid requirements. According to George P. Wilson of the Solid Fuels Administration, such hydrogen sulfide recovery is economical in coke plants which handle at least 4000 tons of coal a day. This includes the majority of U. S. coke plants. Locked up in the world's coal deposits are enormous amounts of sulfur in the form of pyrites. At present, however, only a very limited amount of pyrites is being recovered from coal. Because the pyrites content of coal is seldom more than V 'e found in the land area along the Gulf. Hope, however, has n o t been aban doned. The president of Freeport Sulphur told a congressional c o m m i t t e e : " W e an· t h r o w i n g a lot of money o u t on the rou lette wheel, and when we d o , w e always hope a n d p r a y . T h e m a t h e m a t i c a l chances of finding a. large n e w deposit of sulfur are n o t very good, b u t w e are spending money as if the chances w e r e good, and we h o p e w e will strike." T h e successful u n d e r w a t e r mining of sulfur in relatively shallow water in rea s o n a b l y protected areas has already been achieved b y two U. S. companies: F r e e port and Jefferson L a k e . However, the m i n i n g of sulfur at points miles offshore is a vastly different story. In fact, it is generally c o n c e d e d that the offshore min ing of sulfur is not eronomical by presentC H E M I C A L
da) s t a n d a r d s . On t h e other h a n d , when V. S. sulfur reserves b e c o m e considerablymore* depleted, it is q u i t e possible that offshore operations may take on a new fascination. Of late. Mexico h a s b e c o m e a favorite stamping ground for sulfur prospectors For over a year, Texas Gulf crews have been diligently poking a r o u n d among the salt d o m e s of t h e I s t h m u s of T e h u a n t e p e e , but still haven't hit p a y dirt. O t h e r com panies intent upon discovering workable sulfur deposits have also sent exploratory teams south of the b o r d e r . Activity in the «irea is certain to increase. Last month, the E x p o r t - I m p o r t B a n k of Washington approved a $1,875,000 loan to t h e Mexican Gulf Sulphur Co., w h i c h plans to mine 200,000 tons of native sulfur a year it the 1.5-miIîion-ton San Cristobal Dome deposits. Sulfur Exports F o r years, t h e rest of the world—much like American p r o d u c e r s themselves—confidently a s s u m e d that t h e Gulf Coast sulfur supply was inexhaustible. T h e r e was little to u p s e t the illusion. U . S. native sulfur has long been so a b u n d a n t that the nation has been able to furnish vast q u a n tities to all the rest of t h e world. Over the past q u a r t e r century, t h e U n i t e d States— producer of over 9 0 % of the world's native sulfur—has b e e n shipping, on the average, a b o u t 3 0 % of its production to foreign countries. Just as U. S. sulfur production h a s risen, so have U . S. sulfur exports. F o r example, last year's total exports of 1,440,996 l o n g tons were more than twice the export t o n n a g e of 1939 As 1950 came to a close, t h e U. S. took the a b r u p t step that set off a drumfire of protests in dozens of countries throughout the world. As part of its rearmament and stockpiling program, t h e United States slashed its exports b y approximately 3 0 % . During 1951's first q u a r t e r , total c r u d e sulfur exports to all countries other than Canada w e r e limited to 200,000 long tons. AND
E N G I N E E R I N G
NEWS
T h e recently a n n o u n c e d hali-vear quota: 480.000 long tons. D u r i n g t h e first q u a r t e r of 1951, the United K i n g d o m w a s allotted 81,465 long tons, which, according t o British spokes men, was a full 30,000 tons short of re q u i r e m e n t s , even on a n austerity hasis. Britishers b e g a n grimly p r e d i c t i n g that the c u r b on U. S. sulfur shipments would result in a p r o m p t 20 t o 40 r < cut in the nation's rayon p r o d u c t i o n . At the same time, J. Arthur R a n k ' s D e n h a m Film Laboratories—which h a n d l e about half of Britain's film printing—announced that the sulfur famine, b y sharply curtailing the output of p h o t o g r a p h i c chemicals, would shortly b r i n g to a halt p r o d u c t i o n in large segments of the n a t i o n ' s motion picture industry. T h e n in M a r c h , Washington g r a n t e d t h e U n i t e d K i n g d o m an additional sulfur q u o t a of 19,000 l o n g tons—an action which s u c c e e d e d in q u i e t i n g , at least tem porarily, a few of t h e a n g u i s h e d cries from abroad. To the t u n c of " c h a r i t y begins at h o m e , " some spokesmen in this e o u n t r y have been a d v o c a t i n g that t h e United States reduce its sulfur exports even m o r e drastically— and the sooner t h e better. W o u l d such a policy be sound? Said o n e leading sulfur m a n u f a c t u r e r : " W i t h p r o d u c t i o n outside of the I ' n i t e d States insufficient to take can* of the d e m a n d s o f t h e rest of the world, α severe r e d u c t i o n in sulfur exports n o w would m e a n an almost immediate b r e a k d o w n in industrial activity in many foreign countries. W i t h o u t d o u b t , such a foreign collapse w o u l d h a v e an extremely d a m a g i n g effect u p o n t h e economy of the I ' n i t e d States." Foreign Outlook T h e w o r l d - w i d e sulfur shortatf' has m a d e its impact u p o n t h e Italian supply. Stocks are r e p o r t e d to h e a mere 25,000 tons, or 17*^r of w h a t t h e y w e r e at the e n d of 1949. In the c o m i n g years, Italy will s p e n d about S15 million on mine de velopment a n d drilling in an effort to boost its a n n u a l sulfur output from its present level of 2 5 0 , 0 0 0 tons to 400,000 tons by 1954. Italians h a v e l o n g e m p l o y e d antiquated, highly inefficient m e t h o d s in processing their native sulfur. For e x a m p l e , the heat required in t h e melting step is ordinarily o b t a i n e d by the b u r n i n g of t h e sulfur itself—a practice w h i c h commonly results in a >0 to 409 began working up an allocation s c h e d u l e for sulfuric acid. By mid-April, the o r d e r w a s out. It specified that no compan> in Arizona, California. Colorado, I d a h o , M o n t a n a . N e v a d a . \ e w Mexico, O r e g o n , U t a h , W a s h i n g t o n , and \V\oming m a y use or deliver sulfuric acid without specific authorization from the National P r o d u c t i o n Authority. Companies that purchase 60 tons of acid or less a month are exempt. T h e 11 western states covered b y NPA O r d e r M-45, Schedule 3 , have been a m o n g those most severely af fected by the nation-wide sulfuric acid icarcity. H a r d e s t hit have been western manufacturers of fertilizer and high-octane gasoline. T h e n e w order further provides that » M A Y
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1951
purchasers in all parts of t h e country must henceforth tell their suppliers exactly how the\ propose to u s e their sulfuric acid. In turn, the suppliers must pass along this information t o \ T P A . For t h e t i m e being, specific authorization for t h e delivery or use of sulfuric acid is required only in the l l named western states. However, the reporting mechanism has been set u p for all states n o t only to e n a b l e 'SPA to de termine with some precision t h e national end-use pattern tor sulfuric acid, b u t to permit the agency ultimately to devise a method l)> which sulfuric acid may be regulated o n a n a t i o n - w i d e scale. Several months ago, the Defense Min erals Administration was authorized to lend financial assistance to prospectors and mine operators as a means of stimulating the exploration of new ore deposits. T h e assistance takes t h e form of g o v e r n m e n t loans repayable from the net returns from Λ\\\ ore. concentrate, or metal that may be produced. Government aid in all cases is a fixed penciltage of t h e total cost of an approved project. T h e p e r c e n t a g e de pends upon the mineral; in the case of sulfur, the Government's contribution is 50' ', . Karly t h i s \ear. the State D e p a r t m e n t called together a n International Materials Conference to work out plans for increas ing the production of 12 strategic raw ma terials. On March 1, the sulfur c o m m i t t e e , ι (imposed of representatives from Aus tralia. Belgium (for the Benelux c o u n t r i e s ) . Brazil. Britain. C a n a d a . F r a n c e . Italy. New / e a l a n d . South Africa, a n d the I'nited States. he
