Cyclical process for recovery of elemental sulfur from waste gases
Abstract
Abstract A PROCESS FOR REMOVING SULFUR DIOXIDE (SO2) FROM GASES AND RECOVERING ELEMENTAL SULFUR COMPRISING SCRUBBING THE GASES WITH A SLURRY CONTAINING A METAL SULFIDE UNDER CONDITIONS TO REACT THE SULFUR DIOXIDE WITH THE SULFIDE TO FORM A PRECIPITATE WHICH IS PREDOMINANTLY METAL SULFITE AND ELEMETAL SULFUR. A PORTION OF THE SLURRY IS WITHDRAWN AND THE PRECIPITATE IS SEPARATED THEREFROM. THE REMAINING SLURRY IS RECYCLED FOR REACTION WITH ADDITIONAL SULFUR DIOXIDE AND THE PRECIPITATE IS HEATED UNDER CONDITIONS TO REMOVE WATER THEREFROM AND CONVERT ANY METAL THIOSULFATE THEREIN TO ADDITIONAL SULFITE AND ELEMENTAL SULFUR. SOME METAL SULFATE MAY BE PRESENT. THE ELEMENTAL SULFUR IS SEPARATED, AND THE SULFITE ARE THEN REDUCED TO THE SULFIDE WHICH IS RECYCLED TO THE SCRUBBING SLURRY. PREFERABLY, THE METAL SULFIDE IS AN ALKALI SULFIDE OR ALKALINE EARTH SULFIDE.
Inventors
- 👤 H Strong
- 👤 S Heights
- 👤 J Radway
- 👤 H Cook
Bibliographic Details
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