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:
Mar. 21, 2000
Filed:
Jun. 12, 1998
Toyo Engineering Corporation, Tokyo, JP;
Abstract
Formation of calcium sulfite in a desulfurization column for desulfurizing flue gas is prevented by maintaining the pH of the sorption liquid in the column in the range of 5.5-7.0 and the chemical oxygen demand of the sorption liquid below an upper value determined by the concentration of magnesium sulfate. The upper value of the chemical oxygen demand of the sorption liquid can be controlled by maintaining the quantity of magnesium sulfate in an oxidization vessel arranged downstream of the desulfurization column. The oxidized liquid discharged from the oxidization vessel is neutralized in a double composition vessel, and the thus-obtained slurry is returned directly to the desulfurization column. By preventing formation of calcium sulfite, high-quality gypsum is formed in the double composition vessel.