Method to homogenize the tube temperatures between tubes during processes involving heating of gas flowing in the tubes

摘要

The invention relates to a method for decreasing the spread of the tube temperatures between tubes in a process involving the heating of at least one fluid in a furnace that comprises at least one radiation chamber with radiant walls, at least one essentially vertical row of tubes inside of which circulate the at least one fluid to be heated, and being equipped with burners that heat the tubes, where the method comprises the steps of: determining, for each of the tubes the skin temperature of the tube, selecting the 50% tubes having the lowest temperatures determined, the process being stopped, realizing on each tube selected an operation that decreases the flow of the fluid distributed to said tube while keeping the total flow rate of the fluid unchanged.

主权项

1. A method to homogenize the tube temperatures between tubes in a process involving the heating of at least one fluid in a furnace that contains at least one radiation chamber with radiant walls, at least one essentially vertical row of tubes inside of which circulate the at least one fluid to be heated, and whereby said radiation chamber is equipped with burners that are used in the form of rows, whereby the at least one fluid to be heated is distributed uniformly to the tubes, and whereby the burners heat the tubes, the method comprising the steps of:
a) determining the temperature of each tube; b) selecting the 50% tubes having the lowest temperatures as determined according to step a); c) realizing on each tube selected during step b) an operation that decreases the flow of the fluid distributed, entering in said tube; and d) keeping the total flow rate of the fluid unchanged, therefore distributing uniformly increased flow to the remaining tubes.