EXHAUST GAS PROCESSING SYSTEM AND EXHAUST GAS PROCESSING METHOD

摘要

The present invention is equipped with: a boiler (11) that combusts fuel (F); a denitration device (12) that eliminates nitrogen oxides in the exhaust gas (18) from the boiler (11); an air heater (13) that recovers heat from the exhaust gas (18) after denitration; a dust collector (14) that eliminates particulate matter in the exhaust gas (18) after heat recovery as dust collection ash (16); a desulfurization device (15) that, by means of a lime slurry (20) that is an absorption liquid, eliminates sulfur oxides contained in the exhaust gas (18) after dust elimination; a dehydrator (32) that recovers gypsum (31) from the absorption liquid (30) that is the denitration drainage water discharged from the denitration device (15); a concentration device (41) that eliminates a portion of the water of the dehydration filtrate (33) from the dehydrator (32); a spray drying device (50) provided with a spray means that sprays the concentrated dehydration filtrate (33A) concentrated by the concentration device (41); and an exhaust gas introduction line (L11) that introduces, to the spray drying device (50), a branch gas (18a) branched from the exhaust gas (18).