Reduction of pollution and costs would be the 'direct' payoffs

ONE-STEP STEEL

November 18, 1990|By Kim Clark | Kim Clark,Sun Staff Correspondent

UNIVERSAL, PA. — The father of modern steelmaking, Henry Bessemer, dreamed 130 years ago of a quick one-step recipe for steel: Just boil together coal, iron ore and limestone.

But so far, steel plants have been stuck with a reality of a slow, cumbersome three-step process of heating and reheating that makes mills among the worst air polluters in the country.

That may be about to change.

In a corner building of an abandoned cement plant in this suburb of Pittsburgh, two dozen scientists, engineers and steelworkers are experimenting with equipment that can already cut out the most polluting steelmaking step, and may someday make Mr. Bessemer's dream a reality.

The experiment is a $45 million joint government and industry-funded drive to achieve "direct steelmaking," and is the single most important research project for the U.S. steel industry, industry executives agreed last week.

"I can't think of anything as big as this," said William Jolley, general manager for technology at the Bethlehem Steel Corp. of the American Iron and Steel Institute pilot plant here.

Industry executives said last week that, if research into direct steelmaking succeeds, the steel plants of the 21st century will be far different from those of today, such as Bethlehem's sprawling Sparrows Point facility in Baltimore County.

Gone will be the coke ovens, which are huge, dirty batteries where coal is superheated to burn off impurities, sending dust and other pollutants into the air.

Gone will be the expensive blast furnaces, where the heat-purified coal, called coke, is mixed with iron ore and limestone and seared to about 1,800 degrees Fahrenheit with blasts of hot air to make "pig iron."

Gone, too, will be the basic oxygen furnaces, where pig iron is charged with oxygen and reheated with additional limestone and other compounds to form molten steel, which is then cast into thick forms and squeezed by rollers into salable shapes.

Replacing all three will be a single large sealed furnace, filled with plain coal, iron ore, limestone and a few other compounds. The mixture will be heated and stirred by huge lances that pump out pure oxygen.

In those smelters, temperatures will be so hot -- perhaps reaching 3,000 degrees Fahrenheit -- that almost all polluting gases will be incinerated. Pure steel will dribble out of a tap hole continuously, eliminating the costs of reheating up batches of coke and pig iron.

Outside the smelters will be a few workers making sure the computer-controlled equipment is operating correctly.

Building a direct steel plant would cost only about half of what it would to build a conventional steel plant with a similar capacity, industry executives said. And it would cost millions of dollars less to operate, they believe.

The direct steelmaking would enable the domestic producers to scrap coke ovens, which will need major improvements to meet air pollution standards set by the new Clean Air Act signed by President Bush.

"Coke ovens are very expensive facilities, and it is going to take a tremendous amount of money to get them into compliance," said Bethlehem's Mr. Jolley.

Sparrows Point, for example, is fighting a $1 million lawsuit filed by the state Department of Environment that charges the steel plant's coke ovens violated anti-pollution laws 100 times in the last several months.

Michael Sullivan, spokesman for the department, said last week that the coke oven has been responsible for more air pollution violations than any other part of Sparrows Point.

If the experiment succeeds, direct steelmaking plants of the future would be small, inexpensive, clean and fast, said Ian Hughes, vice president for technology of the Inland Steel Flat Products Co.

"This could reduce the time it takes to turn ore to steel from the 1,000 hours it takes now to 10 hours," he said.

But so far, direct steelmaking is still just a dream.

Though several nations are spending hundreds of millions of dollars to try to win the direct steelmaking race, none has been able to turn the raw materials directly into steel yet.

"Considerable controversy still exists on the viability of this technology," warned Dr. Hughes.

There are many obstacles, said Egil Aukrust, director of the AISI research project.

The temperatures believed needed are so hot and some of the compounds created will be so caustic that scientists are having difficulty finding a material they can use to line the smelter. They haven't found anything that can stand up to direct steelmaking punishment yet, Mr. Aukrust explained.

Though people have been making steel for generations, the behavior of coal, iron and other minerals inside blazing furnaces is still a mystery, he said. Until engineers can figure out how to control the chemical reactions inside the furnaces, they won't be able to turn out consistently high-quality steel, he said.

There are encouraging signs, however.

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