What material is suitable for chimney anti-corrosion?
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This post was last edited by *QIU on 2009-9-5 at 14:58. After wet flue gas desulfurization in China, anti-corrosion measures are generally required for chimneys, especially those used for emitting flue gas. So, which method is the most suitable, or the one with the best cost-performance ratio, for preventing corrosion in chimneys?
We used glass flake coating before.
The anti-corrosion measures for the inner cylinder of wet chimneys after desulfurization mainly include the following methods: 1) Using acid-resistant metal alloy thin sheets as linings; such lining materials include nickel-based alloy sheets (C-276, C22), titanium sheets (TiCr2), etc； 2) Dual-layer lining of glass flake and boric acid insulating brick, GFB-1 ； 3) The second type uses acid resistance, heat resistance, thermal insulation, and heat retention ； To prevent contact between smoke and the inner steel cylinder, lining is installed by spraying methods, such as polyurea or OM-type coatings for corrosion protection ； Different flue gas conditions require different approaches for the corrosion protection design of chimneys, and the associated costs also vary. Therefore, the technical and economic analysis of the chimney solution should be conducted through a comprehensive comparison from the aspects of chimney safety, durability, and cost-effectiveness. Overall, nickel-based alloys and titanium alloys are expensive, while the combination of the new OM anti-corrosion coating and glass flake+boric acid insulation bricks offers a relatively good cost-performance ratio; among these options, the new OM anti-corrosion coating has the best cost-performance ratio. Therefore, this solution is recommended.
At present, the performance of the new types of anti-corrosion coatings remains to be tested; mainly, these coatings are resin-based products, and their heat resistance is not very good.
It depends on what material your chimney is made of. . . If it’s brick-built, just apply cement inside and that will be fine. . . If it is a steel chimney, it is best to use glass flake coating applied in a 2-fiber-to-3-oil ratio for anti-corrosion purposes, and the cost is not high. . .
In China, foamed glass bricks are commonly used; they have a high volume of applications. Scales and polyurea materials have poor heat resistance, while VP requires a high additional load, and OM can only be used in environments with mild corrosion!
I agree with the third floor option; another option is corrosion-resistant mortar
The description on the third floor is quite comprehensive, but the method to be adopted depends mainly on the actual requirements of the site.
When it comes to corrosion protection for chimneys, three aspects need to be considered: the interior and exterior (the exterior part is mainly subject to corrosion from the atmosphere; galvanizing followed by application of anti-corrosive paint is usually sufficient), as well as the bottom and top sections (for the bottom section, corrosion protection along with thermal insulation are important considerations, while for the top section, materials such as corrosion-resistant stainless steel, titanium, or nickel-based alloys are required due to issues like condensation). The specific cost can be determined after looking into these details. As for internal lining corrosion protection, those who have spoken before have already covered it thoroughly, so I won’t go into further detail
Just make the chimney out of fiberglass – we use it a lot in sulfuric acid plants!
Chimneys should generally be equipped with an inner lining. It is advisable to use acid-resistant cement. This post was last edited by LSD0405 on 2009-4-14 23:24.]