The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 08, 1997
Filed:
Feb. 21, 1996
Marco Olper, Monza, IT;
Massimo Maccagni, Sesto San Giovanni, IT;
Engitec S.p.A., Milan, IT;
Abstract
A wet process of regenerative type for removing SO.sub.2 contained in combustion gases in which SO.sub.2 is caused to be absorbed by a diluted aqueous solution of BaS, with a mixed precipitate of elemental S, BaSO.sub.3 and BaSO.sub.4 being formed by the consequent reactions. Sulfur is extracted from the precipitate--recovered by filtration--by using a solution of (NH.sub.4).sub.2 S; the resulting polysulfide is distilled, with pure elemental S and the solution of (NH.sub.4).sub.2 S to be recycled, being obtained. The residual mixture of BaSO.sub.3 and BaSO.sub.4 remaining after sulfur extraction is reduced with coal in a high temperature furnace, in order to obtain BaS to be recycled, as an aqueous solution, to the SO.sub.2 absorption step.