Described herein is a dry sorbent injection system and process for removing sulfur oxides from a flue gas. The process generally comprises treating the flue gas with a dry sorbent material to convert the sulfur oxides to sodium sulfate particulates. The sodium sulfate particulates may then be introduced into a mix tank with water to form sodium sulfate solution. The sodium sulfate solution may then be reacted with a calcium hydroxide slurry to produce a reaction mixture comprising calcium sulfate precipitate and a sodium hydroxide solution. The calcium sulfate (gypsum) may be recovered, and the sodium hydroxide solution may be recirculated to pre-treat the flue gas by removing at least a portion of the sulfur dioxide and/or cooling the flue gas stream.

The present invention relates to a plant and method for the purification of fumes from industrial discharges and/or for the recovery and reconversion of sulfur oxides and/or nitrogen oxides and/or carbon dioxide contained in said fumes. Said method comprises the passage into one or more aqueous solutions, where said aqueous solutions are selected from the group comprising: solution with an acid pH, between 0.5-1; solution at a pH between 3 and 5, at about pH 4; Ca(OH).sub.2 or CaCl.sub.2 or calcium acetate solution; solution at a pH between 8 and 9.