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:
Oct. 19, 1976
Filed:
Dec. 24, 1974
Shigeru Saitoh, Iwaki, JA;
Kenji Kodama, Iwaki, JA;
Tamotsu Miyamori, Iwaki, JA;
Tetsuya Watanabe, Iwaki, JA;
Koji Konno, Iwaki, JA;
Kunihide Yaguchi, Iwaki, JA;
Kureha Kagaku Kogyo Kabushiki Kaisha, Tokyo, JA;
Abstract
A sulfur dioxide-containing exhaust gas is scrubbed by contact with an aqueous solution containing an alkali salt of an organic acid to dissolve sulfur dioxide in the aqueous solution in the form of alkali sulfite. The alkali sulfite in the solution is converted by oxidation into alkali sulfate, which is contacted for reaction with a calcium compound to form calcium sulfate. The calcium sulfate so formed is separated by filtration from the aqueous solution for recovery while the filtrate is recycled for use as the aqueous solution for scrubbing the exhaust gas. The concentration of alkali sulfite in the scrubbing aqueous solution is maintained at a level of less than 1% to ensure efficient removal of sulfur dioxide from the exhaust gas in the form of calcium sulfate.