Dear friend maybe if you take a look in “old discussion you can found some answer like these
”
I assume this injection is for velocity protection / emergency purging of the tubes. If that is the case, you may want to consider using HP steam instead of water altogether – it is much more functional. There are no safety issues related to pump failure, and far less headache trying to balance flows to multiple furnace passes. Is your BFW produced through a demineralizing or softening process? If softened, you may have higher levels of chlorides in the BFW, which will adversely impact furnace tube fouling. Hope this helps
injecting BFW vs steam can present two problems I know of: 1) the latent heat of vaporization is energy wasting in a very heat intensive furnace. One should always make steam at a boiler instead of a process furnace if possible. If your unit is furnace limited then this could cause rate cuts. 2) if your bfw is of poor quality you can get inorganic deposits on your tubes as bfw is vaporized which are catalysts to coking thus reducing furnace runlength.”
best regards
