Electrochemical process for the purification of waste gases, in conjunction with an iron reactor

摘要

The subject of the parent application P 3,447,425 is the removal of nitrogen oxides from waste gases downstream of fossil combustion installations by means of a potentiostatic device, the electrodes required for the reduction to elemental nitrogen predominantly originating from a cathode and additionally from the oxidation of tetravalent sulphur to hexavalent sulphur, using formic acid to prevent precipitation of iron(III) hydroxide. For a further improvement in this process, it is proposed according to the invention that an iron reactor core (2) in the form of preferably metal bodies is bound in the scrubbing fluid and the anode for the electrolysis (4) is attached to the iron reactor core (2). The scrubbing fluid which is passed over the iron reactor core or the container with iron reactors is first contacted with the gas stream, before the fluid, which does not flow over the iron reactor core, is fed to the gas stream in further nozzle planes for simultaneous scrubbing of SO2 and NOx. <IMAGE>