Patent ID: 6143263
Filing Date: 2000-11-07
Classification: B01D

Abstract:
A method for removing SO.sub.3 and SO.sub.2 from a flue gas produced by the burning of a fossil fuel, comprising:providing flue gas to particulate collection means for collecting particles from the flue gas to produce partially cleaned flue gas;injecting into the partially cleaned flue gas, after particles have been removed therefrom by the particulate collection means, an amount of dry sorbent having a particle size range larger than approximately 1.0 microns sufficient to react with and remove substantially all of the SO.sub.3 from the partially cleaned flue gas to produce a substantially SO.sub.3 -free flue gas containing reacted dry sorbent and unreacted dry sorbent;conveying the substantially SO.sub.3 -free flue gas, reacted dry sorbent, and unreacted dry sorbent to wet scrubber means to wet and remove both the reacted and unreacted dry sorbent in the substantially SO.sub.3 -free flue gas, thereby making the unreacted dry sorbent available as a wet reagent for SO.sub.2 removal; andreacting the wet reagent with the SO.sub.2 in the wet scrubber means to remove SO.sub.2 from the substantially SO.sub.3 -free flue gas conveyed to the wet scrubber means.