Cnadian Government Opens Sarnia Rubber Plant
By F. J. V A N A N T W E R P E N , Associate Editor
C A N A D A ' S hopes for synthetic rubber were shown to the press last m o n t h when Dominion officials conducted a t o u r through the synthetic rubber plant a t Sarnia, Ontario. Closely integrated t o the rubber plan of the United States, t h e Sarnia undertaking represents an a d d i tion of some 34,000 tons of Buna S a n d 7,000 tons of Butyl rubber (designed capacities) to the synthetic rubber capacity of the N o r t h American Continent. Begun in J u n e of 1942 and built at an expense of $48,000,000, the plant turned out its first product in September last year, some t h r e e and a half m o n t h s before schedule. Sarnia is unique for things other t h a n its claim to fame as the only rubber tree i n the land of t h e maple leaf. I t is the only plant t h a t has, as part of an integrated operation, full-scale butadiene, styrene, co-polymer, and Butyl rubber facilities. Thus the Canadian Government, through 240
the Polymer Corp., Ltd., has in one area an adaptable unit capable of versatility and economy in the making of rubber. Rubber Processes Base raw material for the Sarnia operations is petroleum, 36,000 barrels delivered daily t o t h e adjacent Imperial Oil Refinery v i a pipe line from the mid-continent fields of the United States. At the refinery, which has been in operation for many y e a r s and is one of the major reasons for the selection of the Sarnia location, a petroleum cut is made, as is usual in petroleum work, and the naphtha-gas oil portion is fed to t h e supersuspensoid cracking coil. T h e supersuspensoid coil is a result of development work started over 10 y e a r s ago and has been done entirely by Imperial technicians. I t uses a catalyst suspended in the oil s t r e a m ; hence the name. The particular virtue of the coil is CHEMICAL
t h a t it produces twice the number of butylènes t h a t regular thermal cracking would make, a n d further, it has made unnecessary the building of the larger a n d more expensive catalytic cracking units. T h e new supersuspensoid unit is working in series with four older suspensoid coils which have been adapted to the so-called supersuspensoid design to make them capable of producing the necessary increase of product required for rubber plant demands. T h e daily capacity is 19,400,000 cubic feet of gases and some 6,225 barrels of light gas oil. These hydrocarbons contain the necessary raw materials—isobutylene, normal butylènes, and ethylene. First step in converting t h e hydrocarbons to rubber is fractionation of the wanted components. This is accomplished in a low-temperature distillation unit which receives the total product required for rubber manufacture from t h e superA N D
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suspensoid coil. From the distilling operat ion 700 barrels of propane-propylene and 1,500 barrels of gasoline are recovered and returned to Imperial. Three products are obtained—ethylene, fuel gas, and a butane-butyiene fraction which contains iso and normal butylènes and butanes. Ethylene is used in making styrene, the butylènes form the basis of a butadiene process, and the butanes, which are separated in a further step, are returned to Imperial as are the excess amounts of fuel gn*. The only remaining hydrocarbon which is not y e t accounted for is benzene, which is purchased from the steel mills at Sault Ste. Marie, Ontario. However, the Saint ( 'lair river freezes during the winter, and t he benzene must be brought in during the summer by boat in sufficient quantity to maintain production during the nonshipping period. . For this purpose tanks capable of holding 1,440,000 gallons have been erected. During the completion of the petroleum plant, there were no hydrocarbons for the, styrene alkylation or the butylène dehydrogenation. The Hiram Walker distillery supplied alcohol, which was processed to supply the necessary requirements for styrene manufacture. The excess production was shipped to the United States and, in consideration of this supply, butadiene was obtained for the Canadian plant so that manufacture of Buna S type rubber could begin. Isobutylene was produced by obtaining a temporary product from Imperial oil and processing a reduced quantity in the isobutylene extraction plant so that Butyl rubber could be produced. All processes are standard and have been described in these pages several times. The GRS rubber is made by the interaction of butadiene and styrene in a soapy emulsion, and after reaction the crude latex is transferred from the glasslined reactors to blow-down tanks where the reaction is stopped by the addition of chemicals. Recovery of the raw materials is also in accordance with standard practice. Butadiene is flashed off and the styrene is stripped from the latex by steaming in a recovery tower. Coagulation is by sulfuric acid and salt, but the plant at Sarnia can take advantage of the abundant amounts of natural brine in and about the district. From the D o minion Salt Co. the Polymer trucks bring in salt brine for coagulation purposes, which on a dry basis would represent 3,500 tons per year. This eliminates two steps, the original drying of the salt and its resolution at the point of use. Screening, filtering, and drying of the GRS follow, and these operations are closely patterned after the usual American practice.
Chemical Co., Midland, Mich., and is being operated by a subsidiary of that organization, Dow Chemical of Canada, Ltd. In the manufacture of styrene the final operation produces ethyl benzene b y combining ethylene and benzene in the presence of a catalyst. The ethyl benzene is then converted into styrene in a hightemperature catalytic cracking operation. The crude product is distilled to produce finished styrene of 99.5% purity. Designed capacity of the styrene plant is 10,000 tons, of which the Sarnia rubber operations will use 9,000 tons yearly. T h e balance of the production will be shipped to the United States. The operation of the styrene plant will require a total personnel of 94, for automatic control instruments have played an important part in the design. This means that the total output of styrene per man will be in the neighborhood of 100 tons per year. The total personnel in the whole operating set up will be 1,600, which calls for a total man-year production of 2 3 to 25 tons. Native labor, producing crude rubber the hard way, can account for about one half to three quarters ton a year per man. The Physical Plant The Sarnia plant is on the site of an old Indian reservation, and in fact a tepee, genuine and built of bark, stands in one corner of the plant grounds. Jimmy Plain, son of a Chippewa chief, dug the first post hole for the rubber unit and later worked in construction.
Styrene Unit
P H O T O . COURTESY O F N A T I O N A L F I L M BOARD
T h e styrene plant was designed by and erected under the control of the «Dow V O L U M E
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The complete rubber producing unit was built and is owned by Polymer Corp. Ltd., a Crown company. The plant has been divided into 10 separate rubber-operating entities: they are the Supersuspensoid cracking coil, operated by the St. Clair Processing Corp., a subsidiary of the Imperial Oil, Ltd., and the same company manages the light ends recovery unit, the isobutylene extraction unit, the butylène concentration unit, and the butadiene unit. The styrene unit is managed by Dow Chemical of Canada, Ltd. The Buna S unit is operated for the government by Canadian Synthetic Rubber, Ltd., a subsidiary of four Canadian rubber companies—Goodyear, Firestone, Goodrich, and Dominion, a subsidiary of the United States Rubber Co. The St. Clair Co. also operates the Butyl rubber operations, steam and power plant, and pumping station. This Canadian rubber plantation sprawls over 185 acres. It represents the combined efforts of some of the largest American construction firms. I t has 22 streets, and has its own hospital, post office, fire hall, police headquarters, ball park, and movie house. Work began on the site June 10, 1942. The first rubber came out of the buildings on Sept. 29, 1943, beating the Jan. '44 deadline by three and a half months. Full-scale operation was expected by Feb. 22. At the height of the construction, about 5,000 men were domiciled in and about the town, which has a normal population of 20,000. Some workmen were forced to live in tents because accommodations could not be found.
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Towers at Polymer's synthetic rubber plant near Sarnia, O n t , used for extracting n-butyiene. M a k i n g the largest was the biggest j o b of Dominion Bridge C o . , and transportation required 5 days on 3 flat cars for the 500-mile trip from Montreal.
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ing 132 feet long. From the crusher it is lifted through a ramp to a height of about 100 feet on a SO^inch belt 528 feet long. When the coal reaches the top floor of the plant, a tripper moving back and forth on rails allows it to drop into any one of the five bunkers. From the bunker the coal falls by gravity into a pulverizer on the ground floor. From the pulverizing mill it is blown up through three pipes into the boiler. Unfortunately, owing t o the scarcity of metal, the coal bunkers over the pulverizers had to be constructed of concrete. Pumping Station PHOTO. COURTESY OF NATIONAL F I L M BOARD
Canada's largest steam and power plant, which is also one of the world's largest. With a rated capacity of 1,375,000 lbs. per hour, it furnishes steam for making rubber and to activate 3 turbogenerators of total 2 9 , 0 0 0 h.p., and uses 5 0 0 , 0 0 0 tons of coal yearly.
Into the whole job have gone an estimated 5,000,000 bricks, 102,700 cubic yards? of concrete, 16,500,000 board feet of lumber, 5,000 tons of reinforcing steel, 156,000 tons of crushed stone, 25,000 medium and large valves. The story of the 25,000 or more valves illustrates the foresight which -nade the operation of Polymer possible less than 14 months after the turning of the first sod. While the clay plateau, on which the plant is built, was still under second-growth forest, a Polymer engineer was appointed t o round up all the valves he could buy of sizes and types that would probably he needed. Without waiting for any of the 4,000 blueprints required for the project;, he and his associates visited city after city in the United States and Canada. They purchased ready-made steel valves from as far away as Los Angeles, as well a s from Britain and Canada. In addition, they placed orders for new valves. From the pool they built up, the contractors were later able to draw at will, and many a week of delay was avoided. To make its annual output of approximately 40,000 long tons of synthetic rubber, the Polymer plant annually requires 500,000 tons of coal, more than 54,000,000,000 gallons of water, 23,000,000 gallons of light-end petroleum, 2,500,000,000 cubic feet of petroleum gas, 2,700,000 gallons of benzol, and enough brine t o contain 3,500 long tons of salt. In addition, great quantities of soap, acids, and other raw materials are used. Steam and Power Plant Largest steam plant in Canada, and one of tbp largest producers of process steam in the world, the Polymer Steam and Power Plant has a rated capacity of 1,375,000 pounds of steam per hour at 4:50 pounds per square inch. The designed generating capacity of the electrical equipment is approximately 32,000 horsepower and consists of two turbogenerators rated
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individually at 10,000 kilowatts (about 13,000 horsepower each), and one at 4,500 kilowatts (about 6,000 horsepower). Average daily load is only about 11,000 kilowatts. The steam and power plant covers 1.2 acres, it is 124 feet high to the top of the fan room roof, and 186 feet to the top of its five smoke stacks. In it are five great boilers, and space has been allowed for a sixth, which might be needed if the rubber plant were expanded. Each furnace is 24 feet square by 100 feet in height and weighs 190,000 pounds. They are suspended from two 4.5-inch Ubolts supported by reinforced concrete. The giant furnaces are covered with a total of 60,000 square feet of high-temperature insulating cement. The insulation reduces coal consumption by nearly 2 per cent, and represents a saving of about 10,000 tons of coal per year. Air for each furnace is supplied by a 200horsepower electric fan and is preheated by exhaust gases. The gases are removed by a 400-horsepower fan for each boiler. Boiler feed water goes through a treater and then through a filter before it enters the boiler. The plant has two treaters, each 30 feet in diameter and 20.5 feet in height, and each handling 96,000 gallons an hour. It has eight filters, each 8 feet in diameter and 20 feet long. Two 1,000-horsepower turbine-driven centrifugal pumps, two 600-horsepower electric motor driven pumps, and one 275horsepower motor-driven pump have been installed to meet the requirements for boiler water. To feed the five boilers calls for 500,000 tons of bituminous coal per year. Stockpiled during the summer at the rate of two shiploads a week, the coal is carried from the Polymer dock on three, 54-inch conveyor belts made of natural rubber and measuring respectively 192, 132, and 60 feet. Great "stork" caterpillar tractors scoop it up and pile it into a 65-foot mountain measuring 1,200 feet by 400 feet. It is carried to a crusher on 30-inch belt-
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The pumping station, through its six steam-driven pumping units, moves 102,000 gallons of water per minute or about 150,000,000 gallons per day. In addition, it has two electrically driven stand-by pumps with a capacity of 57,500,000 gallons per day. The water required for various processes in the rubber plant must be cool, and this was one reason the Sarnia site was chosen. The water flowing down the St. Clair River from Lakes Superior, Michigan, and Huron is never too hot and never too cold. Its even temperature of 34° F. in winter, and approximately 70° F. in summer, is what the engineers wanted, and instead of spending millions of dollars for cooling systems, as was necessary in some synthetic rubber plants, they got it a s a gift from Nature. The St. Clair River water is brought in from a good depth, i s freed from leaves and other impurities, and is then pumped under 55 pounds pressure to the steam and power house, and t o other units of the plant. In certain parts of the plant it is necessary for process purposes to maintain the temperature of the cooling water at 70° F. This is done by recirculating part of the return hot water. The plateau on which the Polymer plant is built is 16 to 26 feet above t h e river level, depending on the season. Polymer Corp., Ltd., was incorporated in Feb. 1942 and was authorized o n March 27, 1942, by Order in Council 2369 at the instance of the Honourable C. D . Howe, Minister of Munitions and Supply, for the purpose of erecting and arranging for the operation of a plant capable of producing the synthetic rubber required for t h e Canadian war program. The directors are: R. C. Berkinshaw, president; D . W. Arnbridge, vice president; J. R. Nicholson, managing director; G. A. Labine, A. C. Guthrie, W. R . Campbell, and A. J. Crawford. Other officers include R. L. Hearn, chief engineer; J. A. Knight, assistant chief engineer; F. S. Lazier, construction works manager; J. W. Gemmell, manager of job administration; G. S. Whitby, head of chemical division; R. H. Brunk, traffic manager; B . C. Kitchen, coordinator of purchasing; and H. R. Smyth, controller.
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VIEWS OF THE SARNIA SYNTHETIC RUBBER PLANT
O n e of the heat exchangers of the extraction section of the butadiene unit, where the rated capacity is 3 0 , 0 0 0 tons a year, from which 3 4 , 0 0 0 tons of Buna S rubber are made. Right. Styrene is purified in this building. Production of styrène was begun just eleven months after the first sod was turned.
«Above. Tons of soap flakes are used in processing Buna S rubber each year. The 2,6G0-gallon acid tank in foreground and the larger vat behind it are of'rot-resistant cypress wood. Not shown is a 30,000-gallon tile-lined tank where untreated latex is stored.
Above. The flow of latex is regulated as it leaves reactors for washing machine. After drying, it is weighed, baled, and shipped to rubber factories to be made into military tires or other end products for war purposes. Left. A t this stage in the making of Buna S, it is called filter cake. Fresh from the washing and drying machine, the rubbery cakes are conveyed on a belt to the tearing rolls where they are minced into millions of tiny pieces.
