Combined process for separating sulphur oxides and nitrogen oxides from flue gases

摘要

Sulphur oxides and nitrogen oxides are jointly scrubbed out of flue gases using a scrubbing liquid containing an amino polycarboxylic acid complex salt and alkali metal ions or alkaline earth metal ions. The reaction products separated in a part-stream from the scrubbing liquid are used to produce, by direct heat exchange using hot gases from a separate firing, at at least 440 DEG C, SO2-rich gas which is subsequently cleaned of undesired accompanying substances.