Process and plant for the preparation of nitric acid

摘要

A multiple shaft drive turbocompressor is bombarded separately by process air and nitrous gas. The process air is compressed to a first pressure and the nitrous gas compressed to a second pressure in a residual gas expander. Production of nitric acid is carried out using a two pressure process, in which ammonia is burnt at a first low pressure using compressed process air and the nitrous gas formed during the burning is absorbed by water at a second pressure higher than the first to produce nitric acid. The non-absorbed gas is relaxed to the surrounding pressure. A multiple shaft drive turbocompressor is bombarded separately by process air and nitrous gas. The process air is compressed to a first pressure and the nitrous gas compressed to a second pressure in a residual gas expander. An Independent claim is also included for the apparatus for producing nitric acid comprising a NH3 burner (7) to burn the ammonia, an adsorption tower (13) to partially adsorb the nitrous gas using water, and a multiple shaft drive turbocompressor (19).