Abstract: The invention relates to a method for the production of nitric acid having a concentration of between 50 and 76%, from ammonia and gas containing oxygen, under pressure, according to a single pressure method or dual pressure method. The expansion of the residual gas takes place in at least two stages in a work efficient manner. At least one device for heating the previously expanded gas to a temperature of more than 450° is disposed between every other expansion stage, using waste heat from the production process of nitric acid.

Abstract: The invention relates to a method for the production of nitric acid having a concentration of between 50 and 76%, from ammonia and gas containing oxygen, under pressure, according to a single pressure method or dual pressure method. The expansion of the residual gas takes place in at least two stages in a work efficient manner. At least one device for heating the previously expanded gas to a temperature of more than 450° is disposed between every other expansion stage, using waste heat from the production process of nitric acid.

Abstract: An apparatus and a process are described for reducing the content of NOx and N2O in process gases and waste gases. The apparatus encompasses at least one catalyst bed comprising a catalyst which is substantially composed of one or more iron-loaded zeolites, and two reaction zones, where the first zone (reaction zone I) serves for decomposing N2O and in the second zone (reaction zone II) NOx is reduced, and, located between the first and second zone, there is an apparatus for the introduction of NH3 gas.

Abstract: A process for the production of nitric acid using the dual-pressure process in which the ammonia is burnt at an initial low pressure with the aid of compressed process air and the nitrous gases formed during combustion are at least partly absorbed by water at a second pressure which is higher than the first. This causes nitric acid to be produced and the pressure of the residual gas, which is not absorbed, is reduced to atmospheric pressure in a residual gas expander for the purpose of winning compression potential. Said process provides a solution aimed at optimising the production of nitric acid whilst improving the production parameters and the materials and energy balances. This is achieved by supplying a multishaft geared centrifugal compressor separately with process air and nitrous gas, the process air being compressed to the initial pressure and the nitrous gas being compressed to a second pressure.