Two stage ammonium sulfate decomposition in flue gas desulfurization process

Abstract

Abstract SULFATE CONTENT IS DECOMPOSED INTO AMMONIUM BISULFATE. A MAJOR PORTION OF THIS AMMONIUM BISULFATE IS RETURENED TO THE ACIDIFIER. A MINOR PORTION, EQUIALENT TO THE AMOUNT OF SULFITE OXIDIZED TO SULFATE IN THE SULFUR DIOXIDE ABSORBER PLUS THE AMOUNT OF SULFUR TRIOXIDE IN THE ENTERING FLUE GAS, IS DECOMPOSED INTO A COMPLETELY GASEOUS PRODUCT MIXTURE COMPRISING AMMONIA, NITROGEN, AND SULFUR DIOXIDE. THE GASEOUS DECOMPOSITION PRODUCTS FROM THE TWO DECOMPOSITION STAES ARE USED IN THE PREPARATION OF FRESH AQUEOUS ABSORBENT SOLUTION. BUILDUP OF SULFATE IONS IN A FLUE GAS DESULFURIZATION PROCESS EMPLOYING AN AQUEOUS AMMONIACAL ABSORBENT IS PREVENTED BY REDCUING A PORTION OF THE SULFATE TO SULFUR DIOXIDE. SULFUR DIOXIDE IS REMOVED FROM FLUE GAS BY ABSORPTION IN AQUEOUS SOLUTION OF MMONIUM SULFITE OR AMMONIA. SOME OXIDATION OF TETRAVALENT SULFUR TO HEXAVALENT SULFUR TAKES PLACE. AT LEAST A PORTION OF THE ABSORBER EFFLUENT SOLUTION IS REGENERATED BY ACIDIFICATION WITH AMMONIUM BISULFATE TO LIBERATE SULFUR DIOXIDE AND TO FORM AN AQUEOUS AMMONIUM SULFATE-AMMONIUM BISULFATE SLURRY. THIS SLURRY IS DECOMPOSED IN TWO STAES. IN THE FIRST STAGE, WATER IS EVAPORATED AND THE AMMONIUM

Inventors

• 👤 Lindsay I Griffin Jr
• 👤 Albert B Welty Jr

Bibliographic Details