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. 24, 1998
Filed:
Feb. 12, 1996
Thomas J Crowe, Palatine, IL (US);
Dennis M Clary, Barrington, IL (US);
UOP LLC, Des Plaines, IL (US);
Abstract
An improved method of continuously controlling a multi-zone heater used in a chemical process has been developed. Each zone of the multi-zone heater has an ideal heat flux, FI, and an actual heat flux, FA, and the difference between the heat flux ratios, .DELTA.(FA/FI), of consecutive zones is to be less than a tolerance, T, where T is in the range of about 0.0 to about 0.1. The control is effected by determining the ideal heat flux, FI, of each zone in the heater and determining the actual heat flux, FA, of each zone in the heater. The difference between the heat flux ratios of FA/FI in consecutive zones is then calculated as .DELTA.(FA/FI). A manipulated variable of the chemical process is then adjusted according to an algorithm relating the changes in the manipulated variable to changes in the actual heat flux of each zone to afford a new value of the actual heat flux FAN where .vertline..DELTA.(FAN/FI).vertline..ltoreq..vertline..DELTA.(FA/FI).vertli ne. for consecutive zones. The process is repeated until .vertline..DELTA.(FAN/FI).vertline..ltoreq.T for all consecutive zones.