>Scott >I am very sorry to miss understand you. I was to hurry and >try to give you quick answer. > >The critical sulfide corrosion issue when the line is not >filling 100 %. You know that sulfide sometime is volatile >and condensed at the top of the line or crude Tank >(investigate your tanks sure you will find corrosion at the >roof you should apply coating on it). This vapor that >condensed at the top of the line is contains electrolyte. >The real name of this phenomenon is vapor space corrosion. >If the temp. Is too high this will not happen. > >Refinery corrosion engineer Mark I didn’t thick there is a chance the H2S vapor is condensing, I believe that sulfurous acid will condense somewhere around 300-350F, our process is seeing around 680F, well above the temperature for sulfidation. Metal dusting is localized carburization which starts occurring around 900-1000F, so that is out. Metal dusting usually involves a mixture of hydrogen, methane, CO, CO2 or another form of light hydrocarbon. I have seen metal dusting once, on the tubesheet of the cold end of the steam generator off the hydrogen reformer. Thanks for your comments Scott