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. 14, 1986
Filed:
May. 29, 1985
A. Ahlstrom Corporation, Noormarku, FI;
Abstract
In a two-stage combustion method first and second circulating fluidizing bed systems are utilized. The first bed system is operated under reducing (sub-stoichiometric) conditions so as to minimize NO.sub.x formation. Solids in the flue gases are separated and returned to the first bed system, while the flue gases are subjected to afterburning in the second bed system. Oxygen containing gas is supplied to the second bed system to effect afterburning, and additionally sulfur absorbing and/or NO.sub.x formation decreasing agents are supplied to the second system. When burning coal, the first system is operated at a temperature of about 700.degree.-1000.degree. C., while the second system is operated at about 600.degree.-950.degree. C. The flue gases may be cooled, just prior to effecting separation of the solids, in one or both of the bed systems.