Abstract

Process and apparatus for the removal of sulfur oxides from sulfur oxide-containing gas with simultaneous production of ammonium sulfate. The process is carried out in a single vessel having an ammonium sulfate scrubbing zone; an ammonium sulfate liquor reservoir having a neutralization zone, a sulfur oxide oxidation zone, and a product removal zone; and a scrubbed gas removal zone. The sulfur oxide-containing gas is introduced into the ammonium sulfate scrubbing zone and passes countercurrent to droplets or a spray of ammonium sulfate liquor. The ammonium sulfate liquor absorbs the sulfur oxide in the scrubbing zone, and the liquor having the absorbed sulfur oxide therein collects in the ammonium sulfate liquor reservoir where aqueous ammonia is introduced into the neutralization zone and an oxygen-containing gas is introduced into the sulfur oxide oxidation zone. The sulfur oxide is converted to ammonium sulfate which is circulated from the ammonium sulfate liquor reservoir to the ammonium sulfate scrubbing zone. Ammonium sulfate product is removed from the product removal zone.