I do not have any scientific data to show for it, but when I started as a process engineer, the PE's that were over me always told me to keep an eye on the overhead product coming out of a vacuum distilltion column for Cd and V. They told me if the Analyzers ever read over 100 ppm of Cd or V that it would accelerate the corrosion of stainless.

Will Chevron Corp.

I would be more concerned with the presence of sodium in the furnace fuel, which if in any significant concentration will form  low melting and corrosive eutectic tube deposits with vanadium. Vanadium as such (without sodium)should essentially oxidize to vanadium pentoxide which I would expect to be minimally deposit forming in the furnance conditions you allude to.

Orenda

I have always heard that V2O5 is highly corrosive for the burner gun and the combustion chamber's environment,piping& steel members etc.

Our forum's more learned mechanical colleagues and corrosion experts may give some good guidance here. or

think posting on corrosion related forum to have a pertinent reply.

Best Regards
Qalander(Chem)

The fuel oil also contains 90 ppm of Na...

Given the sodium content of your furnace fuel, I would suggest adding a magnesium-based compound, in yourcase probably an organo-magnesium compound such as magnesium sulfonate or similar to the fuel being burned to form a high melting, essentially non-corrosive and esaily removed (friable) deposit of vanadium-sodium-magnesium. This will also minimize the formation of SO3 and condensed sulfuric acid in the furnace heat recover section (if this exists) and by neutralization of residual sulfuric acid minimize subsequent corrosion of the section elements.

Orenda