Regarding the installation of the exhaust fan
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Dear friends: Hello everyone! Our company’s exhaust fan is installed behind the water film dust removal system; as a result, during operation the fan is exposed to sulfuric acid-containing gases, which causes rapid corrosion of the fan’s impellers. Could experts please advise on how to solve this problem? Thank you! ! !
We face the same issue; we can only improve the quality of the flue gas, raise its temperature appropriately, and reduce the accumulation of ash on the impellers. Gentlemen, if you have any good suggestions, please share them
Can some liquid alkali be added to water to increase the absorption rate?
Add an alkali tank and a drying tank in front of the fan to remove sulfuric acid vapor and water vapor from it!
We used to be very troubled by this issue as well; we had to replace the impeller every six months. Later, by installing an exhaust fan in front of the dust collector to create positive pressure for dust removal, we solved the problem completely. It’s been two years now, and the paint on the impeller still hasn’t worn off.
Alloy steel and welded wear-resistant layers are generally used; 304 can be employed, and 16MN is also acceptable if the condition isn’t too severe
A similar question seems to have been asked by a comrade before. The current mainstream approach is positive-pressure desulfurization and negative-pressure dust removal (dry method for dust removal). As the original poster mentioned, if it’s not possible to change the location of the exhaust fan, then a mist removal device needs to be added. However, the demisting device is prone to clogging and increases system resistance, requiring improved operation and management.
From the perspective of manufacturing fans, one approach is to use different materials, and another is to thicken the blades
It’s hard to say; it’s a research topic that arose from the design and installation work!
This post was last edited by zjy_007 on 2009-5-6 11:37, with a proposal supporting positive-pressure desulfurization. It is recommended that this problem can be solved through process improvements.
Why not use plastic, lined fans, or fans with ceramic linings, such as those lined with PO or FRP?
By moving the exhaust fan before the desulfurization process, our company has seen good results; we used Beijing Xishan fans for this purpose, but it was necessary to increase the power of those fans accordingly!
Some of our exhaust fans are located in front of the dust collectors, and some of their blades are worn out, not due to corrosion
For positive-pressure desulfurization, it is feasible to use either an alkali tank or a drying tank in front of the exhaust fan; however, the load on the exhaust fan will definitely increase. Has anyone experienced in this field conducted calculations to determine how much the resistance increases, and by how much the current drawn by the exhaust fan rises after its use?
Adding lime to the effluent from the water film dust remover in the sedimentation tank to maintain an alkaline environment should effectively protect the fan impellers.
If wear occurs on the blades due to positive pressure, it is caused by coarse dust particles; adding a gravity settling chamber before the fan’s air inlet can solve this problem.