II— Rayon - ACS Publications - American Chemical Society

they enter Allis-Chalmers rod mills, followed by Mid-Western beaters and Shartle Jordans, finally to yield a very light cream-colored 16-point board m...
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May, 1930

IA17DCSTRIdL - 4 S D ESGIiYEERISG CHEMISTRY

The new liner-board mill a t Lynchburg, operating on the extracted chestnut chips from the John H. Heald Company (Figure 5), is unique because of the particular product manufactured with this raw material, to which is added some sulfate pulp. The Mead interests operate three other plants in the United States utilizing similar spent material, but in each case for the manufacture of corrugating board. The important development which facilitates the manufacture of liner board in this case depends largely upon the softening effect on the extracted chips of a sulfite-soda cook under steam pressure, coupled with the rod-mill treatment. The chestnut fibers, already somewhat softened by the seven-stage countercurrent extraction which they have undergone, are now further disintegrated in the digesters, from which they enter Allis-Chalmers rod mills, followed by Mid-Western beaters and Shartle Jordans, finally t o yield a very light cream-colored lG-point board made on a 144-inch BlackClawson machine. The semi-chemical process is a development of the Forest Products Laboratory. Since tannic acid is harmful in the product, efficient extraction in the tannin plant is doubly profitable in the operation of the joint works. Chemical control has meant the success of this company's work where other enterprisers in the same field haT-e not succeeded in making a profit. A mechanical feature is an efficient 3600-horsepower boiler plant, using pulverized coal, full induced and forced draft with preheated air, designed to run a t 200 per cent rating. Pulp Imports Challenge

The increasing importation through Hampton Roads of Scandinavian kraft and sulfite pulp in small but by no means negligible amounts constitutes a challenge to American chemical engineering. Roughly GO00 tons of each variety are received by water annually, for ultimate consumption in the Virginia paper industry alone. Sulfite spruce for

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rayon plants is received almost entirely from Canada. There is a growing need for research in the sulfate process to increase the narrow margin of profit a t present shown by American operators, as Tell as to lower the cost of kraft pulp to the consumer to a point where foreign pulp cannot compete. It should be possible, in the middle of a southern pine area with as stable and satisfactory a labor supply ns can be found in America, to manufacture kraft pulp profitably and deliver it a few miles aTvay a t some differential amount, homever small, below the price asked by foreign manufacturers after a 4000-mile water shipment. The widespread effect of any one important chemical development is well illustrated in the case of present capacities for nitric acid by ammonia oxidation. Synthetic nitric acid is creating a tightening of the salt-cake market, which to a large extent depends upon the availability of the niter cake from retort acid. Thus kraft manufacturers are beginning to look around for other more elastic means for partially disintegrating southern hard pine to yield the desirable features of strength and finish thus far enjoyed by sulfate products. Capacities for sulfate and sulfite pulp already exist in the state in more than sufficient amount to provide for all local requirements; yet a considerable proportion of this excess pulp, either actual or poterftial, is not consumed by other Virginia manufacturers for economic or competitive reasons. To the exterit to which our resources must be duplicated by purchases is our industrial organization susceptible of simplifying improvements to be brought about through better chemical technology as )vel1 as a broader community spirit. Acknowledgment

The courtesy of the officials of the several plants visited and their release of certain facts as noted are hereby gratefully acknowledged.

11-Rayon Robert E. Hussey' and Philip C. Scherer VIRGINIA

POLYTECHNIC INSTITUTE, BLACKSBURG, V.4.

RIOSG the recent industrial developments of Virginia perhaps the most outstanding and spectacular has been that of the rayon industry. Starting in 1917 with a small plant a t Roanoke, it occupies today a conspicuous position among the rayon producers of this country. Three processes are represented of the four major methods whose products are in general use. Of a world production estimated at approximately 462,500,000 pounds for 1930, the United States manufactures 35 per cent or 162,350,000 pounds, with approximately 28 per cent of this made in Virginia. I n Table I appears the estimated production by states for 1930, together with the percentages of the United States and world production represented by these amounts.

A

Table I-Estimated Production of R a y o n for 1930 b y S t a t e s MILLION POUNDS PER CEKT u. s. PER CENT WORLD Pennsylvania 46.0 28.3 9.95 Virginia 45.0 28.0 9.8 Tennessee 27.5 16.9 5.94 New York 9.7 5.96 2.09 Maryland 8.0 4.92 1.73 Georgia 6.2 3.80 1.34 North Carolina 5.5 3.38 1.09 Ohio 5.5 3.38 1.09 Other states (5) 9.3 5.36 1.77

STATE

Consideration of Tables I and I1 reveals that the United States is the largest world producer by a greater amount than ever before; that Pennsylvania and Virginia occupy I

Member, Industrial Committee of the Virginia Section.

leading positions among the states. The United States production increased about 35 per cent in 1929. Table 11-World COUNTRY United States Italy Great Britain Germany France Other countries

Production of R a y o n for 1927, 1928, a n d 1929 1927 1928 1929 Million bounds 97.70 123.13 75.05 47.00 36,OO 59.00 38,80 52.00 53.10 31.00 41.00 45.00 21.00 30.00 37.00 64.16 79.30 86.93

Total

-_-

266.00

347.00

--

404.16

Distribution of R a y o n Manufacture by Process for 1930 PROCESS u. s. VIRGIKIA Million pounds Viscose 130.0 29.5 Acetate 17.5 3.0 Cuprammonium 4.0 Nitro 12.0 12:o

Table 111-Estimated

Virginia Plants

Virginia has within its borders five plants in production, distributed as shown in Figure 1, in Part I of this paper. The Du Pont Rayon Company operates two plants in Virginia, one at Richmond (Figure 1) and the other at Waynesboro. The viscose process is used at the Richmond plant with a n estimated annual output of 3.5 million pounds

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INDUSTRIAL AND ENGINEERING CHEMISTRY

of rayon. Operation was started on June 1, 1929, and reached full capacity in September. About 1800 operators are employed in this unit. It is equipped to pump 25 million gallons of James River water per day and has a large settling lake for purification. The Waynesboro plant was started in the fall of 1929 and is said to use the acetate process operating under the Rhodiaseta French controlled patents, producing “acele” yarns with a capacity of 2 million pounds per year. A model power plant employing some of the newest mechanical devices forms part of the completed unit.

Vol. 22, No. 5

district, which is growing rapidly, has shown a surprising tendency toward the increasing use of rayon. Northern and southern markets are within easy reach of all parts of the state. The excellent transportation systems of the state are responsible for the speed with which the finished products reach the market. Eight different railroad systems are actively cooperating in the industrial development of Virginia. The port of Hampton Roads offers excellent facilities for water transport,ation to all parts of the world.

Figure 1-Richmond Plant of Du Pont Rayon Company

The water supply is a unique feature of this plant, however, a single spring existing on the plant site with a flow sufficient to meet all possible needs. Water flows from the spring a t the correct process temperature, eliminating all necessity for mechanical control of the humidifying process. It is planned to establish here a t least seven additional units of the same capacity in the near future, according to report. The Industrial Rayon Corporation plant a t Covington, Va. (see page 461, this issue), is equipped for the manufacture of fine denier and multifilament yarns by the viscose process. On the basis of 150-denier yarn, the annual capacity of this plant is placed a t 6 million pounds. There are about 2000 employees housed in 300 dwellings in the Industrial Rayon village. Process steam is a by-product of the power plant; the filtration plant has a daily capacity of 3 million gallons of water. Over one mile of railroad sidings connect the plant with the railroads of the state through the Chesapeake and Ohio Railway. The Viscose Corporation has in operation a t Roanoke, Va., what is said to be the largest single plant in the world for the manufacture of rayon by the viscose process. Completion of the sixth unit early in 1928 brought the annual capacity to approximately 20 million pounds with a force of 6000 operators. Affiliated with a company whose main plant is a t Tubize, Belgium, this firm operates a t Hopewell, Va., the only plant in America producing nitrocellulose or Chardonnet rayon. It was started in 1921 and has reached an annual production of 12 million pounds. It employs approximately 3500 operators.

Abundant supplies of industrial water are available throughout the state; neighboring coal fields and local sources of such heavy chemicals as sulfuric acid, soda ash, and carbon bisulfide go far to meet the requirements of the local rayon manufacturers. Labor is particularly attractive, as the foreign radical element is practically non-existent a t present. These advantages, together with the comparatively mild and uniform weather in this state result in low production costs. Within the past two years the tax system of the state has been modified to offer added inducements to industrial development.

Reasons for Location

Future Outlook The prospects for further expansion in this field in Virginia are very promising. Organized in May, 1929, by the Tubize Artificial Silk Company of America and the American Chatillon Corporation, the American Acetate Silk Company will produce rayon by the acetate process to the extent of about 2,250,000 pounds annually, according t o current estimates. The location of this plant has not been definitely decided, but no new construction is contemplated in Virginia so far as is known. According t o R recent announcement by J. L. Warner, senior consulting engineer of the E. I. du Pont de Nemours and Company, another plant will be built by that company in Virginia as soon as conditions in this locality warrant it. With these plants in operation this state will have a production which may be expected to stimulate new and more advanced scientific research a t local universities in the chemical technology of rayon manufacture, as well as the training of suitable chemists and engineers for the needs of this modern silkworm.

Virginia occupies a strategic position in regard to the raw materials and markets for rayon production. The cotton and wood pulp are produced either within the state or by the neighboring states. The textile market of the Piedmont

As this issue goes to press, the Du Pont Rayon Company announces the immediate erection of a new cellophane plant, to be located next t o the viscose process unit in operation near Richmond. The plant is estimated to cost over $2,000,000 and will employ about 400 operators.

May, 1930

IhTDUSTRIALA N D EA'GINEERING CHEMISTRY

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M a i n Mill Buildings, M a s o n i t e Corporation, Laurel, Miss.

The Masonite Process' Robert M. Boehm MASONITB CORPORATION, LAUREL,MIS.

I

N RECEXT years public attention has been directed as

never before to the elimination of waste and the profitable utilization of by-products. All wastes today-agricultural, industrial, and thc like-are undergoing cloze scrutiny. As a result many materials which were considered worthless, or practically so, are now being converted into commodities of great economic value. This has been particularly noticeable in the insulation-board industry, where bagasse, cornstalks, eel grass, and wood waste are raw materials. From an economic point of view, what could be more praiseworthy than to take these materials, of little or no real value, and convert them into a product which serves as a buffer between mankind and nature, keeping him cool during the summer's heat, warm during the freezing months of winter, and shutting out noises which disturb his rest. History of Process The Masonite Corporation is now slightly over three years old. In that time it has progressed from a small experimental station operating two guns and turning out about 40,000 feet of board daily, to the present plant, equipped with nine guns and turning out over 130 million feet annually. It is one of the few developments in the industry which can boast of an entirely new process. Instead of reducing the wood structure by chemical means or by grinding, the chips are exploded under a steam pressure of 1000 pounds per square inch, thus preserving the fiber structure without loss through chemical action. The originator of this process is W. H. Mason, and he has brought it through the experimental stage to its present position in the insulation field. Mr. Mason was formerly with Thomas Edison and for seventeen years worked with that great inventor on problems of many types. He first thought of exploding wood structures while investigating the removal of naval stores from sawed lumber. Khen this Received March 3, 1930. Presented before the Division of Cellulose Chemistry at the 79th Meeting of the American Chemical Society, Atlanta, Ga., April 7 to 11, 1930.

development was successfully established, he turned his attention to the explosion process. The first experiment in the production of Masonite was rather crude. A gun was made by drilling a hole in a large piece of shafting. It was filled with chips, a small amount of water was added, and a tapered steel plug was fastened in the end. The gun was then placed in a vise and heated with blow torches until it was assumed that a pressure of about 1000 pounds per square inch had been reached. The steel plug was then struck with a long bar and the fibers were blown out of the gun with a terrific report. Enough of the fibers were gathered up to demonstrate the possibility of securing a suitable fiber structure in this manner. The tapered steel plug could not be found; it had apparently been blown several hundred yards. The fiber was formed into a board on a small hand frame, run through a wash wringer to remove a portion of the water, and then pressed and dried t o form insulation board. The method of making Presdwood was discovered by accident. The idea had been conceived of manufacturing a very hard, dense board, but efforts t o produce it by first pressing the wet lap and then drying the board in an oven were unsuccessful. I n a neighboring paper mill a small letter press equipped with steam-heated platens was used to obtain the moisture content of pulp samples. This was used in some of the preliminary experiments. One day the steam on the press was carefully turned off and a portion of wet lap was placed in the press. For some reason hlr. hlason forgot about the board in the press for about 2 hours. When he went back, he discovered a leaking steam valve on the press and found that the wet lap had been under pressure and a relatively high temperature for 2 hours. When the press was opened, much to everyone's surprise, a very hard, dense board had been formed. This was the first piece of Presdwood. Since the day when the first piece of Masonite was run through a wash wringer the process has steadily grown. A pilot mill was first established, consisting of three guns,