DOUBLE PRESSURE PLANT FOR PRODUCTION OF NITRIC ACID AND METHOD OF OPERATION THEREOF Russian patent published in 2025 - IPC C01B21/26 C01B21/28 C01B21/40 B01D53/56 C25B1/04 

FIELD: chemistry.

SUBSTANCE: invention relates to production of nitric acid. Invention relates to plant and method of operation of high-pressure purge column in plant of double pressure for production of nitric acid, including: air compressor increasing pressure to 2–6 bar (low pressure, LP); ammonia/compressed air mixture feed converter ND for ammonia oxidation and production of gaseous ND gas mixture NO_x/steam; NO_x gas compressor increasing pressure to 9–16 bar (high pressure, HP); high-pressure absorber unit, where nitrogen oxides in the NO_x high-pressure gas stream react with water, the product contains nitric acid, dissolved nitrogen oxides and tail gas; HP purge column for removing dissolved nitrogen oxides from the product stream with a stripping medium, which provides streams of stripping nitric acid and stripping gas containing NO_x, the purge column operates at a pressure comparable to that of the absorber and communicates with the oxygen-enriched HP gas source for its supply as a stripping medium. Plant comprises means for directing stripping gas from NO_x to outlet side of compressor of NO_x-gas, wherein high-pressure water electrolyser is used to produce high-pressure gas enriched with oxygen. Method comprises operating a purge column at a pressure comparable to that of an absorber; supply of purge column with high-pressure gas enriched with oxygen; directing the stripping gas with NO_x to the outlet side of the NO_x-gas compressor; gas enriched with oxygen is provided by electrolyser.

EFFECT: increased efficiency and improved energy balance of nitric acid production process.

10 cl, 4 dwg, 1 tbl, 4 ex