dew point corrosion
Thread Content
If there are acidic gases and water vapor in the exhaust gases, and the pipe temperature is above the dew point, corrosion should relatively be not very severe. Could one then consider using insulation tape to wrap around the pipes in order to keep the temperature above the dew point, thereby achieving corrosion prevention?
This method can be used for short pipes, but not for long pipes
Among the measures to prevent dew point corrosion is raising the feed temperature so that the pipe temperature remains above the dew point temperature. LZ is considering using insulation tape around the pipes to keep the temperature above the dew point, thereby achieving corrosion prevention; this approach is feasible.
Thank you to both of you for your answers. But why don’t long pipes work? Our pipeline is about 20–30 meters long – is that considered a long pipeline?
20 to 30 meters is considered long. If an insulation layer is added, the load on the supports will be quite high. Raising the temperature works better.
In our Daoyao facility, the exhaust gases manage to corrode the flue of the water scrubber within just one year; in winter, ice is used to seal it, and during the Spring Festival, the flue needs to be repaired. Therefore, I think it would be better to design that section of the flue as a replaceable component
Agree with what was said on floor 5. Generally, to prevent dew point corrosion, it is necessary to keep the flue gas temperature above the dew point temperature of water vapor; this can be achieved by returning some of the hot air from the air preheater outlet to the inlet in order to raise the air temperature. Corrosion-resistant materials can also be used, as well as insulation measures for the flue and convection areas.
Thank you all for your detailed answers. I also want to ask: after wrapping it with a heating strip, is it necessary to add insulation material on the outside? What is the most commonly used material for such insulation?
Condensate acid and acid sludge will definitely be generated.
Is it the dew point of water vapor or that of the acidic liquid? The temperatures of the two can sometimes differ significantly, so be sure not to get them mixed up.
The dew point of the acid solution – our temperature is above 350 degrees; if we can maintain this temperature, there should be no condensation of acid, right? What is acid mud?