Simultaneous SO2/NOx wet scrubbing process with scrubbing water treatment for purifying combustion exhaust gases

摘要

Processes are known for purifying SO2 and NOx from combustion exhaust gases by use of a wet circulation scrubber with scrubbing water treatment, the scrubbing water of which contains iron(II)-EDTA or iron(II)-NTA complex. In order to be able to carry out a process of this type having technically improved results and lower expenditure, according to the invention it is proposed that the simultaneous wet scrubber is operated on an alkali basis (sodium) and the additive addition is hydrated lime. In the scrubber (2), the untreated gas (1) is scrubbed with scrubbing water circulated via a pump (3) and pipe (4) and, freed from the pollutants dust, HCl and HF, leaves the prescrubber (2) and, via the demister (18), enters the SO2/NOx simultaneous scrubber (5). Here, the prepurified flue gas is freed from sulphur oxides and nitrogen oxides by a scrubbing solution which is circulated via a pump reservoir (6) of a pump (7) and pipes (8). The flue gas leaves the scrubber (5), purified, at (14). IMAGE