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:
Sep. 11, 1990
Filed:
May. 28, 1986
Hans-Dietmar Maury, Ahlen, DE;
Wolfgang Buslowski, Ennigerloh, DE;
O&K Orenstein & Koppel Aktiengesellschaft, Dortmund, DE;
Abstract
A method for the heat treatment of finely granular material, particularly for the manufacture of cement, employs a preferably multi-stage cyclone preheater (2), a rotary tubular kiln (1), a cooler (6) and a kiln off-gas line (5) which is formed between rotary tubular kiln (1) and cyclone preheater (2). The off-gas lines provides a passage substantially in upward direction for the off-gases of the rotary tubular kiln (1) and receives tertiary air fed thereto for the combustion of additional fuel. The tertiary air is provided in two streams from the cooler (6), which cooler is connected behind the rotary tubular (1) on the material side, the streams being introduced into the kiln off-gas line (5) at different heights. In order to separate the combustion of the additional fuel from the precalcination and to avoid the production of injurious nitrogen oxides (NO.sub.x), the additional fuel is fed exclusively to the lower partial stream of the tertiary air in such a manner that sub-stoichiometric combustion take place before the entrance of the second partial stream of tertiary air. The second partial stream of tertiary air effects a complete combustion of the additional fuel in the upper part of the kiln off-gas line (5).