Patent ID: 6512156
Filing Date: 2003-01-28
Classification: C10G,G01N,Y10S

Abstract:
A method for controlling cracking severity in a cracking furnace, the cracking furnace having at least one cracking tube, the cracking tube being heated to a temperature, the cracking tube containing a feed mixture that is fed into the cracking tube and an gaseous effluent that flows from the cracking tube, the feed mixture having a composition and a residence time in the cracking tube, the method comprising the steps of:(a) determining the near infrared spectrum of the gaseous effluent in-line by shining a beam of near infrared light first through a first protective gas stream, then through the gaseous effluent, and then through a second protective gas stream to a detector; and (b) changing a process variable selected from the group consisting of the temperature of the cracking tube, the composition of the feed mixture and the residence time of the feed mixture in the cracking tube according to the determination of step (a).