Abstract:
The invention is a method for reduction of sulfur trioxide in flue gases which includes (a) combusting air and petroleum coke in a combustion zone to produce a particulates, sulfur trioxide, and sulfur dioxide-containing combustion product gas; (b) passing the combustion product gas from step (a) to a dry electrostatic precipitator for removal of particulates and recovering the combustion product gas substantially free of particulates, or alternatively rearranging the steps so so that step "b" follows steps "c" and "d"; (c) admixing particulates with the combustion product gas from step (b), to produce a first mixture; (d) passing the first mixture from step (c) to an air preheater for cooling the first mixture and heating the air for combustion with the petroleum coke, wherein the sulfur trioxide in the first mixture condenses on the particulates, to produce a second mixture containing combustion product gas containing sulfur trioxide condensed on particulates and sulfur dioxide; (e) passing the second mixture from step (d) to a wet scrubber for removal of substantially all of the sulfur dioxide, sulfur trioxide, and particulates, to produce a combustion product gas substantially free of sulfur dioxide, sulfur trioxide, and particulates; and (f) passing the combustion product gas substantially free of sulfur dioxide, sulfur trioxide, and particulates from step (e) to a stack for release to the atmosphere.