ALEXANDRIA, Va., March 19 -- United States Patent no. 12,252,754, issued on March 18, was assigned to JFE STEEL Corp. (Tokyo).
"Molten steel denitrification method and steel production method" was invented by Hidemitsu Negishi (Tokyo) and Rei Yamada (Tokyo).
According to the abstract* released by the U.S. Patent & Trademark Office: "A molten steel denitrification method, wherein an extremely low nitrogen concentration range is stably reached in a short time without use of a top-blown gas, is a denitrification process wherein CaO-and-Al2O3-containing slag formed by a combination of an Al addition step of adding a metal-Al-containing substance to molten steel to deoxidize and turn the molten steel into Al-containing molten steel and a CaO a...