Process for reducing the NOx emissions downstream of fossil-fuel power station boilers with simultaneous utilisation of the heat of reaction to heat up the gases downstream of flue gas desulphurisation

摘要

It is known to decrease by catalytic route the nitrogen oxides contained in the exhaust gases of fossil-fuel power station boilers and to decrease the sulphur oxide likewise present in these exhaust gases by flue gas desulphurisation. Since it is frequently required, depending on the position of the power station, to elevate the scrubbed flue gases to at least 80 DEG C, according to the invention it is proposed that the heat from the NOx reduction (2) is utilised to reheat the scrubbed flue gases downstream of the flue gas desulphurisation (4) via a heat exchanger system (5) which is connected upstream of a stack (6). Some of the heat produced can additionally be uncoupled as utility heat. <IMAGE>