PROCESS OF CONVERSION OF SULFUR DIOXIDE INTO SALTS OF COMMERCIAL INTEREST

摘要

A conversion process of SO2 into salts of commercial interest comprising the steps. of : a) carry out a first absorption stage comprising contacting an input gaseous stream (1) comprising SO2 with a first absorption phase (2) comprising alkaline metal, alkaline earth metal, or ammonium sulfite and bisulfite at a pH ranging between 8 and 4.5, b) oversaturate the phase comprising alkaline metal, alkaline earth metal, or ammonium sulfite and bisulfite, and induce precipitation of alkaline metal, alkaline earth metal, or ammonium metabisulf ite crystals, c) carry out a second absorption stage comprising contacting the output gaseous steam (1') from the first absorption stage (a) with a second absorption phase (6) comprising alkaline metal, alkaline earth metal, or ammonium sulfite at a pH between 9 and 7, and d) oversaturate the phase comprising alkaline metal, alkaline earth metal, or ammonium sulfite, and induce alkaline metal, alkaline earth metal, or ammonium sulfite crystal precipitation.