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:
Dec. 10, 1985
Filed:
Aug. 11, 1983
Peter B Nielsen, Copenhagen, DK;
F. L. Smidth & Co. A/S, , DK;
Abstract
A method and an apparatus for calcining pulverulent raw material, in particular cement raw meal, wherein the material is calcined suspended in a stream of hot gas in a calcining zone (4) in an overheated atmosphere by burning fuel in a stream of oxygen-containing gas in the zone, and precipitated in a precipitation zone (9). The rate of combustion of the fuel is accelerated by maintaining a temperature within the range 900.degree.-1250.degree. C. in the calcining zone by dividing the raw material into two streams (22',22) introducing and calcining only the first stream of material (22') in the calcination chamber (4). The temperature of the hot suspension withdrawn from the calcining zone is reduced by 100.degree.-300.degree. C. to a level within the range 800.degree.-1000.degree. C. by suspending the second stream of material (22) in the hot suspension during withdrawal thereof from the calcination chamber (4) and before the calcined material is precipitated in the precipitator (9).