Process for the absorption of sulfur oxides and the production of ammonium sulfate

摘要

A flue gas mixture containing sulfur oxides is scrubbed in a countercurrent spray tower absorber with a spray of ammonium sulfate liquor and the scrubbed gas stream containing ammonia aerosols, sulfur trioxide aerosols and ammonia slip is passed to a wet electrostatic precipitator for the removal of the aerosols and slip. The ammonium sulfate liquor in the absorber system is passed into a separate reaction tank where ammonia and air are injected. The ammonia and sulfur oxides react in the separate reaction tank to form ammonium sulfite which is oxidized to the sulfate by the air. The gases and vapors from the separate reaction tank are separately scrubbed and the gases then returned to the absorber.