Intragranular tubing sulfidation prevention
Intragranular tubing sulfidation prevention
(OP)
Greetings, I first must apologize. I am not a full-fledged engineer, just a mechanically minded guy. But nonetheless I have a problem of metallurgy that is beyond my scope.
I operate a 1260 psi, wood-fired boiler burning at approx 1300-1500 deg F. The boiler is McBurney brand and was first fired in 2005. We have intragranular sulfidation attacks on the gas side of our superheating section so bad as to render our .150" tube wall to .020" or rupture.
We are preparing to re-tube the boiler and would like to only have to do it once. So far all processes my supervisor has researched have been able to combat the sulfur content but are not sufficient to withstand the heat of continued use.
If anybody has a fantastic solution either metallurgical or chemical coating I would be greatly interested in hearing about it.
Thank you for your time.
I operate a 1260 psi, wood-fired boiler burning at approx 1300-1500 deg F. The boiler is McBurney brand and was first fired in 2005. We have intragranular sulfidation attacks on the gas side of our superheating section so bad as to render our .150" tube wall to .020" or rupture.
We are preparing to re-tube the boiler and would like to only have to do it once. So far all processes my supervisor has researched have been able to combat the sulfur content but are not sufficient to withstand the heat of continued use.
If anybody has a fantastic solution either metallurgical or chemical coating I would be greatly interested in hearing about it.
Thank you for your time.





RE: Intragranular tubing sulfidation prevention
Your boiler supplier, the tube supplier, or the insurance carrier should be able to recommend someone.
Here is a little information on some of the approaches to your problem. These approaches don't cover all the methods used to protect tubes.
The first link is to an article about corrosion of boiler tubes. The second is to a little information on over layered tubes. The third is a company that does overlay weld in the field.
http://ww
RR03/03500/03500.pdf?id=NACE-03500&soc=NACE
h
http:
RE: Intragranular tubing sulfidation prevention
RE: Intragranular tubing sulfidation prevention
RE: Intragranular tubing sulfidation prevention
RE: Intragranular tubing sulfidation prevention
RE: Intragranular tubing sulfidation prevention
That asked, the advice given above is spot on. There are fuels that are chock full of sulphur (oils, coal, black liquor and even natural gas with trace amounts) that have boiler tubing designed to survive in that type of combustion environment.
Is McBurney the actual manufacturer of the boiler or just the packager of the boiler system? I haven't dealt with them in quite a few years, but back when I did, they packaged a variety of different OEM's boilers with the balance of the plant equipment; fuel handling, air pollution control, feedwater systems, etc in order to furnish a complete boiler system package. If the latter, you might try contacting the original manufacturer of the boiler for their advice.
rmw
RE: Intragranular tubing sulfidation prevention
RE: Intragranular tubing sulfidation prevention
RE: Intragranular tubing sulfidation prevention
RE: Intragranular tubing sulfidation prevention
In general for an alloy to resist sulfidation you need high Ni. Cr may impact overall corrosion resistance but to minimize the penetration of S take Ni.
Weld overlay has been used extensively, but it isn't perfect. You will get cracking in the welds and localized corrosion at those locations. It is not uncommon to see 20 cracks per inch of weld after a couple of years of service.
= = = = = = = = = = = = = = = = = = = =
Plymouth Tube