Process and plant equipment for the short-term propulsion of one or several turbines coupled to an air and/or nitrous gas compressor in a plant for the production of nitric acid

A manufacturing plant for the production of nitric acid by ammonia combustion with air to produce nitrous gases that are compressed and contacted with water in an absorption unit to thereby produce nitric acid;

• said manufacturing plant comprising:
• (a) an ammonia combustion chamber wherein ammonia is catalytically combusted with air to form nitrous gases, said combustion chamber containing therein catalyst material;
• (b) a steam generating system to produce steam using the heat produced by ammonia combustion, said steam generating system consisting essentially of a steam generating chamber fed by steam and boiler water lines positioned within a boiler/superheater chamber that is in nitrous gas communication with the ammonia combustion chamber;
• (c) an absorption unit in nitrous gas communication with the boiler/superheater chamber of the steam generating system, wherein in said absorption unit nitrous gases are contacted with water to produce both nitric acid and an exhaust gas;
• (d) a compressor system which serves to compress and transport either the air stream fed to the plant or the nitrous gas stream within the plant or both, said compressor system comprising at least one compressor coupled with a turbine or turbines, said turbine or turbines being propelled by steam from the steam generating system or by decompression of preheated exhaust gas from the absorption unit;
• (e) at least one heat exchanger for preheating the exhaust gas from the absorption unit with heat from the nitrous gas stream, said exhaust gas stream being preheated before said exhaust gas is fed to the exhaust gas decompression turbine, if any, said heat exchanger being positioned in the nitrous gas path downstream from the boiler/superheater chamber;
• and
• (f) at least one heat accumulator means positioned in, or as a part of, the nitrous gas path, the exhaust gas path or the steam generating system, said heat accumulator means serving to store sufficient heat energy to power said compressor system until essentially all of the nitrous gases which have not been converted to nitric acid are transported to the absorption unit, in the event that the ammonia supplied to the ammonia combustion chamber is shut off.