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:
Aug. 22, 1978
Filed:
Oct. 27, 1976
Soren Bent Christiansen, Copenhagen Valby, DK;
F. L. Smidth & Co., Cresskill, NJ (US);
Abstract
A method is disclosed for heat treating pulverulent or granular raw material such as cement meal. Raw material is directed to at least two multi-stage preheater strings, the first string communicating with the kiln by a smoke riser pipe and the second string having a calciner positioned at its lower end portion. The raw material directed to the first preheater string is divided into two divisional flows with the first divisional flow comprising substantially the maximum amount of material which can be substantially completely calcined by hot gases exiting the kiln. The first divisional flow of raw material is directed toward the upper material inlet end portion of the kiln so as to be entrained by the hot gases exiting the kiln, and the hot kiln gases and entrained material are directed to the first preheater string. The second divisional flow is directed to the second preheater string where it is calcined either alone or with raw material directed to the second string. The substantially completely calcined material exiting the first preheater string and at least partially calcined raw material exiting the second preheater string are directed to the upper material inlet end portion of the kiln at a location and in a manner so as to avoid entrainment by the hot exit gases and pass down through the kiln for further heat treatment. A plant is disclosed for practicing the inventive method.