The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 09, 2025
Filed:
Apr. 05, 2019
Yara International Asa, Oslo, NO;
YARA INTERNATIONAL ASA, Oslo, NO;
Abstract
The present application relates to a process for the reduction of NOx from a gaseous effluent generated in the production of fertilizer comprising the acid digestion of phosphate ore in the presence of urea, wherein said gaseous effluent generated has a NOx composition of 70 to 100 mole % NOand 0 to 30 mole % NO, comprising the steps of: a) contacting said gaseous effluent for 0.5 to 15 seconds with ozone, thereby providing a resultant gas mixture wherein NO and NOpresent in the NOx are oxidized to higher nitrogen oxides; and; b) removing higher nitrogen oxides from said resultant gas mixture; wherein urea is present during said acid digestion of phosphate ore in an amount of 0.25 wt % or less based on the weight of said phosphate ore; and; ozone is added to said gaseous effluent in an ozone/NOx ratio ranging between 0.5 and 1.4.