Time needed for Propper passivation?

[Dan2539]

I just thoroughly washed, scrubbed with BKF, rinsed and dried an old keg with some tiny rust areas. How long should I keep the keg open and exposed to air for proper passivation? Is passivation something that takes time or is it instantaneous?

 

[conpewter]

I was listening to a brewcast on metals a few months back and John Palmer stated that passification is pretty much instantaneous. (at least as far as homebrewers are concerned) You can get a thicker passification layer by using some acids etc but that's not easily done.

http://thebrewingnetwork.com/shows/Brew-Strong/Brew-Strong-09-29-08-Metals-that-Affect-Your-Beer

 

[Brewer3401]

I worked for a tank-container business that dealt with a lot of stainless tanks (20,000 liter +)

Buffing and passivating was constantly being done.

Buff out stainless and put on acid - I think that's all there is to it. The acid will evaporate and it's done.

 

[Dan2539]

Cool, thanks for the help guys.