Patent ID: 11905172
Assignee: YARA INTERNATIONAL ASA
Field: Chemical engineering (Chemistry)
Classification: CPC C  B  F  Y | IPC B  C  F

Claim 0:
1. A process for producing nitric acid, comprising the steps of:
(a) catalytically combusting a mixture of ammonia and an oxygen containing fluid, in an ammonia burner, thereby forming an ammonia combustion stream comprising nitric oxide;
(b) oxidizing at least partially the nitric oxide in the ammonia combustion stream of step (a) to nitrogen dioxide;
(c) absorbing in an aqueous solution, by means of an absorber, the nitrogen dioxide contained in the stream of step (b), thereby forming a concentrated aqueous nitric acid solution, wherein the oxygen containing fluid is supplied to the ammonia burner via an oxygen containing fluid supply line, wherein in at least one section of the oxygen containing fluid supply line the oxygen containing fluid is a liquid;
(d) increasing the pressure of the oxygen containing liquid in the oxygen containing fluid supply line thereby obtaining a pressurized oxygen containing liquid, wherein the pressurized oxygen containing liquid has a pressure of at least 10 bara;
(e) evaporating or boiling the pressurized oxygen containing liquid obtained in step (d), thereby obtaining a pressurized oxygen containing gas; and
(f) expanding the pressurized oxygen containing gas over a first turbine.