Chickasaw Ordnance Works A N ADDITION to Memphis industries ^ during 1940 was the $25,000,000 explosives plant built by E. I. du Pont de Nemours and Co., Inc., for the British Purchasing Commission. Situated several miles outside the city limits, it manufactures smokeless powder and trinitrotoluene (TNT). An explosives plant requires a large area because the buildings must be located some distance apart for safety. Approximately 5,000 acres of land were purchased during the early part of 1940 and about one half of this was fenced in. The first ground was broken during June and the first smokeless powder granulated in December. Six months from the start of construction to the start of production is an enviable record for a plant of this kind. T N T manufacture did not start until February 1941, because erection of this portion of the plant was not started as soon as the smokeless powder section. Another record established during the plant construction was a safety record of over 3,000,000 man-hours without a lost-time injury. The personnel of the plant averages at present approximately 3,000, most of whom were originally residents of Memphis and Shelby County. Memphis was selected as the location of this plant for several reasons. First, the area is several hundred miles distant from the seaboard, which minimizes the danger of aerial bombardment. Second, cotton linters are available for the manufacture of smokeless powder. Memphis is the cotton-marketing center for the MidSouth. Third, the supply of high-quality labor is plentiful. Fourth, numerous railroad facilities connect in all directions for shipment in of raw materials and shipment out of finished products. Fifth, the source of good water, absolutely necessary
for the processing of smokeless powder, is large and unfailing. Sixth, practically all the raw materials entering into the manufacture of smokeless powder and T N T are available in sufficient quantities within a radius of 500 miles. The plant consists essentially of six different areas: Power, which is the source of all water, steam, and electricity used. Acid, where nitric acid is manufactured by the oxidation of anhydrous ammonia and where nitric acid and sulfuric acid are mixed together. Recovered acids are also concentrated in this area for further use. Nitrocellulose, where the cotton linters are nitrated to nitrocellulose and the resultant nitrate purified and stabilized. Powder, where the purified nitrocellulose is mixed with other ingredients and solvents and processed into smokeless powder, which is then given a solvent recovery, water-dry and air-dry treatment. Upon completion of the air-dry treatment, the powder is thoroughly blended and packed into boxes for shipment. An important part of this area is the solvent section wherein ether is manufactured and recovered alcohol and ether rectified. TNT, where toluene is nitrated to D N T and T N T by means of mixed sulfuric and nitric acids, purified and packed for shipment. Maintenance, where a considerable portion of the personnel is employed in caring for and replacing equipment. The maintaining of equipment in a chemical manufacturing plant involves constant surveillance to keep production running smoothly. Of equal importance in plant operation are the service groups—accounting, employment, safety, fire protection, plant protection, transportation, and technical. The last group consists of approximately 125 chemists and chemical engineers, responsible for the quality of the raw matrials and the finished products.
The Buckeye Cotton Oil Co. r
I ^HE Buckeye Cotton Oil Co., a wholly owned subsidiary of the Procter & Gamble Co., was started with a mill at West Point, Miss., when the cottonseed industry was still in its early stages of development. That mill has since been discontinued, but further additions by purchase or construction have enlarged the company until at present there are 15 active mills throughout the South. The operations at Memphis include the Hollywood Mill, largest cottonseed oil mill in the world. The Binghamton Oil Mill at
Memphis crushes soybeans, and the Chemical Pulp Division purifies cotton linters for plastics, rayon, films, and smokeless powder. The Buckeye Cotton Oil Co. established its first laboratory in 1910. With the growth of laboratory control, two division laboratories were established, one in Atlanta for the southeastern territory and one in Memphis at the Binghamton plant for the valley territory. In 1926 mill laboratories were established as a part of the standard equipment at each of its
major crushing points, and chemists were employed to handle all local analytical work.
Hollywood M i l l The Hollywood Mill is a relatively modern one-floor mill and represents upto-date practices in the laboratory control of its many operations. The photograph on the opposite page shows the layout of the mill and storage facilities. Typical processes of a cottonseed oil mill, of which there are many in the Memphis area, are cleaning, storing, and drying, delinting, hulling, rolling, cooking, pressing, grinding cakes for meal, and pelleting. The seed is stored in large tanks and houses equipped with fans and ducts for ventilation to prevent "heating". The batteries of conical-top seed storage tanks developed by Buckeye are a familiar landmark in the South. Drying is carried out only as wet seed require it. The seed are cleaned by screening in two stages— first, to remove boles and large trash and second, sand and dirt. Finally an air draft and a magnetic separator finish removal of foreign matter. The cotton gins receiving the seed from the farmer have removed the long fibers leaving short seed hairs or lint. The delinter used in oil mills is similar to a gin, but because it removes short fibers the saws are set closer together and are sharper. The lint is usually removed in two passages through the delinters giving a medium length or first-cut lint and a short or second-cut lint. The first-cut lint goes mainly into production of highclass mattresses, while second-cut lint is purified for chemical uses. The cottonseed hulls are cracked in a bar or disk huller which in either case passes the seed between two edges with a differential speed. The hulls are then separated from the meats by a combination of screening and air separations. There is a ready sale for cottonseed hulls as roughage for cattle. To prepare the meats for the cooking and pressing operations, they are passed between rollers driven at the same speed and in direct contact with one another. In passing downward through the stand of rolls, the seed are subjected to successively greater crushing pressure and delivered in thin flakes. This procedure crushes some of the cells and brings the structure to condition so that cooking and pressing will liberate the oil. Cooking cottonseed is a n art which has not been entirely untangled by scientific investigation. In his book on "Cotton-
Tne AMERICAN CHEMICAL SOCIETY assumes no responsibility for the statements and opinions advanced by contributors to its publications. Published by the AMERICAN CHEMICAL SOCIETY, Publication Office, 20th & Northampton Sts., Easton, Penna. Editorial Office. 1155 16th St., N . W.. Washington, D. C ; Telephone, Republic 5301; Cable, Jiechem (Washington). Advertising Department, 332 West 42nd St., New York, N . Y.; Telephone, Bryant 9-4430. Entered as second-class matter at the Post Office at Easton, Penna., under the act of March 3, 1879, as 24 times a year on the 10th and 25th. Acceptance for mailing at special rate of postage provided for in Section 1103, Act of October 3, 1917, authorized July 13, 1918. Annual subscription rate, S2.00. Foreign postage to countries not in the Pan American Union, $0.60; Canadian postage, $0.20. Single copies, $0.15. Special rates to members. No claims can be allowed for copies of journals lost in the mails unless such claims are received within 60 days of the date of issue, and no claims will be allowed for issues lost as a result of insufficient notice of change of address. (Ten days' advance notice required.) "Missing from files" cannot be accepted as the reason for honoring a claim. Charles L. Parsons, Business Manager, 1155 16th St., N. W., Washington, D. C , U. S. A.
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similar to cottonseed but, since there is no lint to be removed, soybean processing is much simpler than that for cottonseed. At the Bingham t o n Mill modern expellers instead of the older hydraulic presses are used to extract t h e oil. The expeller is a continuous mechanical press resembling a huge sausage grinder. The cylindrical barrel is made u p of bars set from 0.001 to 0.040 inch apart. As the worm forces the soybeans, which have been prepared merely by cracking and drying, through this barrel, the oil seeps out through the openings between the bars. A soybean mill has only t w o products, oil and cake, whose uses are similar to those from cottonseed. Chemical Pulp Division
Hollywood M i l l , Buckeye Cotton O i l Co. seed Products", Thornton says, "The function of cooking is to permit the proper adjustment of the moisture, rupture of oilbearing cells, coagulate the proteins, coalesce the gummy materials, destroy molds and other lower organisms, make the cake more palatable and more wholesome by inactivating the gossypol." T h e meats are delivered from the bottom of the cooker t o the former where they are wrapped in a press cloth of human or camel hair and lightly pressed to preform the cake. A typical box press will hold 15 cakes arranged one above the other. After reaching maximum pressure, approximately 4,000 pounds per square inch, it is held constant long enough to allow the oil to drain from the cakes. Twenty minutes is a common drainage time, although it is varied to meet various conditions of drainage, oil price, etc. After settling, the oil is ready to be shipped to the refiners. Upon removal of the cake from the press, the cloths are taken off in an automatic stripper and any soft oily edges are cut off by an automatic trimmer. A considerable amount of the cake is sold as such to mixed feed manufacturers. Most of the cottonseed cake is ground to meal of definite protein content and sacked for sale to feed mills and livestock feeders. The control of the protein is accomplished by regulating the amount of hulls with the cake. An increasingly larger proportion of cottonseed meai is made into pellets— a form preferred for range feeding of cattle. They are formed by chopping off V O L U M E
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the meal as it is extruded in cylindrical form through a die. Binshamton O i l M i l l Growing soybeans in the cotton territory is a recent development. The beans are received and stored in a manner
The pulp plant was built shortly after the first World War for the purification of hull fiber. This product, however, was economically suitable for only a limited number of grades of paper, and about 1925 the use of cotton linters for chemical pulp was developed for the expanding rayon industry. With the outbreak of the present war an increasing amount of purified linters are being used for smokeless powder. Since the average cottonseed oil mill producing linters operates for only about six months a year, enough lint must be stored to carry the pulp plant through the nonproducing season. The lint is tested and graded when stored so that the proper type c a n be selected from the various kinds of pulp. T o prepare a charge for digestion, the bales are opened and the cotton broken up and cleaned pneumatically a s far as practicable. The digester is a typical autoclave into whicb
Huller room at the Hollywood Mill APRIL
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is charged the cotton and sodium hydroxide solution. The charge is brought up to pressure and, after suitable cooking time, is blown into the wash tanks. The black liquor is drained off, and wash water is used to free the cooked lint from alkali. Bleaching is done with hypochlorite solution under carefully controlled conditions of concentration, time, and temperature. After a proper bleach is attained, an acid sour is given and the charge washed. The chemical pulp may be finished as bulk or sheet. The bulk pulp is pumped from the storage tubs to a preliminary dehydrator, through rubber wringer rolls
and a picker, and fed into a textile dryer. The dried pulp is baled, inspected, wrapped in heavy kraft paper, weighed, and tagged. Sheet pulp is carried through a Fourdrinier machine and cut into any desired size for handling by the plastics and rayon manufacturers. The pulp plant at Binghamton is o n e of the few of this kind in the United States. T h e chief products made from bulk pulp are acetate and cuprammonium rayon, paper, nitrocellulose, and films. The sheet pulp goes chiefly into high-strength viscose rayon yarns, paper, and floor covering (linoleum).
Chemistry's Contribution to the Cottonseed Industry GENE H O L C O M B National Cotton Council, Memphis, Tenn. WIIEN Harry D. Wilson, Louisiana's venerable Commissioner of Agriculture, was a boy he derived great personal pleasure from the fact that his father's cotton gin was located on a river's bank. This meant that he did not have to spend his Saturdays, as did many boys in the fall, hauling cottonseed to a safe distance from the gin and burning it. He could simply dump the lot into the river and let the current carry it away. Today cottonseed bring to Commissioner Wilson's great host of farmer friends more than SI00,000,000 each year. The story of this transformation from waste product to a $200,000,000 industry is principally a story of chemistry. The first problems of utilizing cottonseed were mechanical rather than chemical. During the first half of the 19th century the removal of linters and the separation of the hulls from the kernels engaged the attention of experimenters. It was generally believed that the oil which the seed contained would find a market as an illuminant. A number of statements were made to the effect that it would displace whale oil in American lamps and drive Yankee whalers from the seas. But whatever the possibilities of cotton oil m a y have been in the field of illumination, they were never realized. The discovery of petroleum was made at approximately the same time that efficient machinery for delinting and hulling cottonseed was invented, and the new, natural product provided America with illumination until the advent of gas and electricity. Cottonseed oil had to find other markets. In finding such markets, the chemist played a most important part. Even while cottonseed crushing was in its experimental stage a few far-sighted scientists had predicted that the oil's future lay in the field of foods. They claimed it to be the equal of the finest olive oil and suggested that it be used for the same purposes. Since the oils produced by the 440
early millers with their crude equipment and without facilities for refining was a considerably different product from the cotton oil of today, these early claims were based more on optimism than fact. Even when oil mills began to crush seed in appreciable quantities during the 1870's, most of the oil was exported. The little that was consumed in America usually went into the s o a p kettles. But about 1880, when the number of profitably producing mills had increased to 45, a number of events transpired which were destined to shape the whole future course of the cottonseed industry. One was the introduction of cottonseed oil into oleomargarine, a new food product imported that year from France. At first the oil was added in small quantities, but later in increasing amounts. In this way a new market in the highly important food field was opened to cottonseed by t h e chemist.
Cotton sins C H E M I C A L
At first, however, the effect of margarine upon cottonseed oil was more indirect than direct. Introduction of steam rendering in the meat packing industry had yielded a product known as prime steam lard. Few packers marketed this product themselves. Instead they sold it to a group of processors known as lard refiners, who stiffened the lard by the addition of tallow, lard stearin, or better grades of lard, and sold it under their own name. Development of the margarine industry created a strong demand for two products of the packing industry—natural lard and oleo oil. The latter, made from the highest grade of tallow, yields as a by-product a hard edible stearin. The packers, naturally, welcomed t h e opportunity to sell these two products to the margarine industry. As a result the lard refiners were left without the best grades of lard and tallow with which t o refine prime steam lard. Large quantities of oleo stearin were available, however. It was this combination of circumstances which lead to the discovery of one of the first formulas including cottonseed oil in a new product. The formula called for 8 parts oleo stearin, 38 parts cottonseed oil, and 60 parts lard, and was developed by the N . K. Fairbank Co. of Chicago, one of the first firms in the fats and oils field to employ an industrial chemist, inaugurating the policy in 1879. The chemist was William D . Allbright, a young graduate of Massachusetts Institute of Technology. The above mixture of lard, oleo stearin, and cottonseed oil, together with the application of chemistry to t h e manufacture of food fats, marked the beginning of a whole new industry—the shortening industry. A large number of technological developments followed, greatly increasing the usability of cottonseed oil. One of the Carriers to using substantial quantities of ton oil was the fact that it was yellow in color, while the consumer expected a cooking fat to be white. In the early days cotton oil was bleached by exposure t o the sun. Large tanks placed on the roofs were used b y several manufacturers. About 1880 Allbright and Eckstein introduced the use of fuller's earth for bleaching both cottonseed oil and lard. T h e oil or lard was heated with from 0.5 to 2 per cent of fuller's earth, depending upon the strength of the latter. At first the earth was removed by settling and decantation. Later the filter press was introduced and, to avoid loss of oil by retention in the earth, dry live steam was passed through the press. This procedure made possible efficient bleaching with little loss of oil. Shortly after the introduction of chemical bleaching, use of sodium hydroxide in refining was discovered. Previously oil had been refined by the use of pearlash. David Wesson introduced the sodium hydroxide method in the Fairbank plant and it proved to be both efficient and economical. Even with chemical refining and bleachA N D
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