Yobbo
Mechanical
- Apr 22, 2003
- 85
L.S.,
I am confronted with the problem that rust formation in a flue gas channel in a power plant sometimes results in emission of rust flakes. This is environmentally unacceptable. The flue gas temperature is 150 degrees Celcius in general. The flue gas channel is made of ordinary carbon steel. The rust formation mechanism differs from atmospheric rusting a bit, because the sulphurdioxid in the flue gas lets sulphur penetrate and diffundate through the rust layer to the channel wall. There it seems to perform some katalytic function.
In my urge to prevent this phenomenen coating or changing the channel wall material seem to be the only solutions. I wonder though whether there are no other solutions such as applying some rust inhibiting paint or layer, that slows down or even eliminates the rusting mechanism. I did find some materials like Hammerite and Rust-o-leum. They seem not to be able though to cope with the higher temperature in combination with the presence of sulphur dioxide.
By the way I can state that during normal operation the concentration of sulphuric dioxide is thus low that the dew point temperature is not higher than the flue gas temperature.
Through this thread I would like to find out whether there are industrially available paints or coatings that not only separate the flue gas atmosphere from the channel wall, but also actively passify the rust mechanism. I am thankfull for any suggestions.
With best regards,
Karel Postulart
Karel Postulart, The Netherlands
Nuon Power Generation
I am confronted with the problem that rust formation in a flue gas channel in a power plant sometimes results in emission of rust flakes. This is environmentally unacceptable. The flue gas temperature is 150 degrees Celcius in general. The flue gas channel is made of ordinary carbon steel. The rust formation mechanism differs from atmospheric rusting a bit, because the sulphurdioxid in the flue gas lets sulphur penetrate and diffundate through the rust layer to the channel wall. There it seems to perform some katalytic function.
In my urge to prevent this phenomenen coating or changing the channel wall material seem to be the only solutions. I wonder though whether there are no other solutions such as applying some rust inhibiting paint or layer, that slows down or even eliminates the rusting mechanism. I did find some materials like Hammerite and Rust-o-leum. They seem not to be able though to cope with the higher temperature in combination with the presence of sulphur dioxide.
By the way I can state that during normal operation the concentration of sulphuric dioxide is thus low that the dew point temperature is not higher than the flue gas temperature.
Through this thread I would like to find out whether there are industrially available paints or coatings that not only separate the flue gas atmosphere from the channel wall, but also actively passify the rust mechanism. I am thankfull for any suggestions.
With best regards,
Karel Postulart
Karel Postulart, The Netherlands
Nuon Power Generation
