18 Oct
2002
18 Oct
'02
5:19 p.m.
Sellam Ismail wrote:
<<snip>>
and therefore contains no radiation. Apparently, air
since the first
atomic bomb test is now filled with background radiation, and because so
much air is used in the smelting process, a lot of the radiation gets into
modern steel making it unsuitable for some applications (such as medical
test equipment where radioactive isotopes are used as part of the
operation).
Unless the steel is refined using either the open hearth or the Bessemer process,
there is no "air" used at all. Both of these processes were notorious for air
pollution problems. More commonly, in the last 40 years or so, steel refining is done
using the basic oxygen steel process. Pure oxygen is blown into a
brick-lined vessel charged with liquid iron and scrap steel and the
impurities burn off at. Alloying elements are added as needed, and the
steel is poured off into ladles, and further processed. Electric arc
furnaces are also used for specialty steels (stainless comes to
mind....) and probably other applications as well.
The bottom line is, there are more efficient ways to make steel than to
use air to burn off the impurities...
Stan