From comments made by U.S. Steel officials to C&EN, only one minor chemically related change is involved in the process. Because of the high-speed movement of the strip, a longer cleaning section is needed on which is added the trisodium phosphate cleaning agent and, when necessary, the scale-removing pickling solution. Another, more mechanical feature is the 700-foot-long annealing furnace with sensitive controls for holding, heating, and cooling the many different variations of steels with their many specifications. About 50 other galvanizing lines are in operation around the country. The number should increase in view of the rising demand for unpainted corrosion-resistant steel. In 1957, the automobile industry was buying 125,000 tons of steel so treated. Today the figure is close to 900,000 tons. Another big user is the appliance industry, which purchased 270,000 tons in 1967. Other existent and emerging markets include roofing, house siding, and machinery. Total annual consumption by 1971, according to zinc and steel industry sources, will be about 7 million tons.
mediates such as alcohols, olefins, paraffins, and some nonionics which are coming into the market." Already, acting on the poor growth potential, three U.S. producers have withdrawn from the detergent alkylate business. Last year, Phillips Petroleum Co. and Chevron Oil Co. discontinued producing alkylates, and Allied Chemical closed its Buffalo, N.Y., alkylates plant. And last month Allied sold its only other alkylate plant at North Claymont, Del., to American International Refining Corp., which will continue operating it. This year, Mr. Hill estimates, Free World production of detergent alkylates will total 1775 million pounds with a market value of $175 million. Of this total output, 1155 million pounds will be the "soft" linear alkyl benzene sulfonates (LAS) and 620 million pounds will be the "hard" branched alkyl benzene sulfonates (ABS). Evaluating the Free World supplydemand situation, Mr. Hill projects continuing overcapacity. He estimates overcapacity (as a percent of demand) of LAS compounds at 21.2% in 1969 and projects a decline to 16.4% in 1972. Similarly, he estimates overcapacity of ABS compounds at 35.5% in 1969 and projects a decline to 27.0% in 1972. The Free World demand for the nonbiodegradable ABS surfactants is plateauing, he points out. The 1969 demand of 602 million pounds will rise to no more than 640 million pounds in 1972. In contrast to the Free World, the U.S. supply-demand situation for LAS is in balance, Mr. Hill says, largely as a result of the three recent shutdowns. U.S. capacity at the end of 1968 was 580 million pounds a year and actual production was 540 million pounds.
DETERGENTS:
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THE CHEMICAL WORLD THIS WEEK
six strands of superconducting niobium-titanium alloy. The copper acts as a shunt to provide a temporary path for electric current if the superconducting strands should lose superconducting properties—for example, if they get too warm. The coils are kept at 4.5° K. (-451.3° F.) by liquid helium to make them superconducting. A 30kw. power supply brings the magnet to a full field strength of 1900 amp. in approximately 2.5 hours. After the field is established, the electric power consumption is negligible. By contrast, it would continuously require about 10 million watts to keep a conventional magnet at full strength—enough to supply a town of 10,000 people. This is where the operational costs are saved. Assuming a 50rA operation for 10 years, a conventional magnet would cost $4 million to run; the superconductor is expected to cost some $400,000 to operate for 10 years. GALVANIZED STEEL:
Process Speed Doubled U.S. Steel last week unveiled the industry's first high-speed galvanizing lines for producing zinc-coated steel, the type resistant to corrosion. Demonstrations were held simultaneously in Fairless, Pa., near Philadelphia, and at Fairfield, Ala., near Birmingham. The process can turn out coated sheet steel at speeds of up to 700 feet per minute, more than twice as fast as by conventional methods. A third such facility is under construction at U.S. Steel's Gary, Ind., sheet and tin mill near Chicago. The immediate advantage to the chemical industry is quicker shipment of construction steel in the East and South. The Fairfield line is U.S. Steel's first galvanizing operation on the East Coast. Those industries in the East will have particular advantage. Prices, however, are not expected to drop. Moreover, the steel is limited to the flat-surface type and does not include piping. A big need in the chemical industry today is for piping steel coated only on the outside, with the inside kept clear. The key to U.S. Steel's process is a so-called "air knife" operation that regulates the zinc coat just after the strip emerges from the molten-zinc bath. The company would not comment on any details except to say that atmospheric air—not a synthetic gaseous mixture—is sprayed at room temperature across the surface. The higher the pressure the thinner the coat. 10 C&EN FEB. 3, 1969
Galvanizing line Zinc coating at 700 feet per minute
Market Growth Slows "Detergent alkylates—I'd never venture into the business," commented one chemical marketing man during coffee break. Another replied, "In terms of investing today, it looks like poor profits all the way out." These remarks were overheard following a talk on detergent alkylates which Shell International Chemical's H. A. W. Hill gave at the Soap and Detergent Association's 42nd annual convention in New York City. Mr. Hill, marketing manager, wax cracker derivatives, prefaced his analysis of the worldwide detergent alkylate situation with the point: "The bonanza growth rate of detergent alkylates is over. Their growth is being slowed by other detergent inter-
· ^ U.S. demand for linear detergent alkylates will grow 2% per year through 1975 Millions of pounds
900 800
U.S. capacity
700
600 Total U S. demand
Exports
·£·
500
'r* 4001
U.S. domestic demand
1 1 1 1 1 1 1965 1967 1969 1971 1973 1975
Source: Shell International Chemical Co.
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