Process for removal of divalent sulfur compounds from waste gases

Abstract

A process and apparatus for removal of volatile divalent sulfur compounds from waste gases. Volatile organic compounds are advantageously removed in the same process. The divalent sulfur compounds are oxidized in a combustion zone, then preferably removed from the combustion gas, as by absorption or adsorption. The divalent sulfur compound and any VOCs are oxidized in either a catalytic or thermal combustion zone, after which the combustion gases are cooled by transfer of heat to the contaminated gases entering the combustion zone. A regenerative heat transfer reaction system is preferably used. Catalyst may comprise a noble metal, or oxides of Cr, Cu and/or Mn. A catalyst degraded by deposition of sulfate or sulfite salts on its surface may be reactivated by in situ decomposition of such salts. Reactivation also removes such salts from the heat transfer storage beds of a regenerative heat transfer reaction system.