Fired Heaters - Purge Steam

[S.G]

Dear All,

According to Section 15.3 of API Standard 560, for forced-draft systems, the forced-draft fan can be used to purge the firebox in lieu of purge steam. Does the API text refer to diesel fuel or gaseous fuel?

 

[georgeverghese]

Section 15.3 does not exclude either fuel source when combustion air is the purge medium. Many fired heaters use combustion air as the purge medium on FD units with natural gas as fuel source. Agreed, steam would be ideal.