METHOD FOR BAGHOUSE BROWN PLUME POLLUTION CONTROL

摘要

ABSTRACTBaghouse SOx/NOx pollution control process comprisinginjecting from 1 to 25% urea or ammonia along with dry,finely divided sodium bicarbonate or Nahcolite, anaturally occurring form of sodium bicarbonate. Theprocess removes both SOx and NOx from the flue gases ofutility and industrial plants, incinerators and the likeby dry injection into a flue gas duct a sufficientdistance upstream of a baghouse to collect spent reagentand additive. The sodium reagent reacts with the SO2 toform sodium sulfate and also removes NOx in the form ofNO. The urea or ammonia additive prevents theconversion of NO to NO2 by the sodium reagent, andreduces the concentration of the NO2 in the exit fluegases to below the NO2 brown plume visibility threshold(about 30 ppm NO2, not corrected to 0% O2, depending onambient conditions). The additive may be used wet(sprayed into the flue gases in a concentrated watersolution) or dry.