US Patent Issued to YARA INTERNATIONAL ASA on March 18 for "Bleaching tower and method for nitric acid production" (Norwegian Inventors)

ALEXANDRIA, Va., March 19 -- United States Patent no. 12,252,399, issued on March 18, was assigned to YARA INTERNATIONAL ASA (Oslo, Norway).

"Bleaching tower and method for nitric acid production" was invented by Halvor Oien (Porsgrunn, Norway) and Arnulf Idar Melgard (Skien, Norway).

According to the abstract* released by the U.S. Patent & Trademark Office: "A vertical bleaching tower for removing dissolved nitrogen oxides from an aqueous nitric acid solution using a stripping gas such as air, nitrogen, oxygen or combinations thereof in a process for producing nitric acid, comprising a structured packing; a liquid distributor comprising a feed box having a serrated weir for distribution of the aqueous nitric acid solution comprising the ...