Process for producing sulfur from sulfur dioxide or ammonium sulfites
OwnerGeorge W. Lewis, Jr.inventor
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Abstract
A method is disclosed for treating flue gas and the like for sulfur dioxide removal and sulfur recovery. The flue gas, containing a minor but polluting amount of sulfur dioxide, is contacted with ammonia in a reaction chamber. The reaction product is caused to precipitate onto a heat sink where it is mechanically removed on a continuous basis. The removed compounds are recycled by subjecting them either in solid or vaporized form to carbon monoxide between 140.degree. F and 600.degree. F to obtain sulfur and ammonia.
Claims6
A process for producing ammonia and sulfur which comprises subjecting a first solid substance selected from the group consisting of ammonium sulfite, ammonium pyrosulfite, ammonium bisulfite, and a mixture of any two or more of said compounds to carbon monoxide gas at a temperature above 140.degree. F and below 250.degree. F and in the absence of oxygen until substantially all of said first substance has been converted to ammonia and sulfur, and recovering the ammonia and sulfur produced.
A continuous process for reducing SO.sub.2 content of contaminated gases containing SO.sub.2 and water vapor which comprises:
- a. adding ammonia to the contaminated gases;
- b. removing the ammonium compounds which form;
- c. subjecting as a solid phase the ammonium compounds which form to carbon monoxide at a temperature above 140.degree. F and below 250.degree. F and in the absence of oxygen, whereby ammonia and sulfur and carbon dioxide will be produced;
- d. recovering the sulfur produced and
- e. adding the ammonia produced to the contaminated gases in continuing the process.
Dependencies are inferred from the claim text.