Plant for the production of nitric acid, a related process and method of revamping

A dual-pressure plant for the synthesis of nitric acid comprising:

• a reactor, wherein a stream of ammonia is oxidized to provide a gaseous effluent containing nitrogen oxides;
• an absorption tower, wherein nitrogen oxides contained in said gaseous effluent react with water,
• wherein the adsorption tower provides an output product stream containing nitric acid and nitrogen oxides and a tail gas,
• said reactor operating at a reaction pressure and said absorption tower operating at an absorption pressure greater than the reaction pressure;
• a compressor, which elevates the pressure of the gaseous effluent of the reactor from the reaction pressure to the absorption pressure;
• said plant comprising at least a first bleacher and a second bleacher,
• said first bleacher stripping nitrogen oxides away from said output product stream of the absorption tower with a first stripping medium, providing a partially stripped nitric acid stream and a nitrogen oxides-loaded stripping medium, wherein said first bleacher receives the product effluent of the absorption tower and no line is present directly connecting the absorption tower with said second bleacher,
• said partially stripped nitric acid stream being fed to the second bleacher, said second bleacher stripping nitrogen oxides away from said partially stripped nitric acid stream with a second stripping medium, providing a stream of bleached nitric acid,
• said nitrogen oxides-loaded stripping medium being recycled to the discharge-side of said compressor.