Corrosion in ammonia-based desulfurization
Thread Content
This post was last edited by liaifeng on 2018-8-3 22:31. An ammonia-based desulfurization process was added after the Super Claus desulfurization process, but corrosion is quite severe; 306L material is used for the desulfurization towers. Experts, please analyze this
We have previously designed desulfurization processes using the three-stage Claus + ammonia method; where exactly is the corrosion occurring in your case? The flue gas tower?
Both the desulfurization tower and the circulation tank are corroded, but the corrosion at the welds of the overflow pipeline in the desulfurization tower is particularly severe. Multiple repairs have been carried out, and even large-scale replacement of the tower’s material has failed to resolve the issue
Both the desulfurization tower and the circulation tank are corroded, but the corrosion in the desulfurization tower is more severe. Since the plant started operating half a year ago, there have already been 7 instances of corrosion in the overflow pipeline of the desulfurization tower. Moreover, large areas of the material used in the tower have been replaced, yet the problem still persists
It’s hard to say; there are definitely no chloride ions in the exhaust fumes, but they are present in water. Everything is calculated, so theoretically there shouldn’t be any chloride ions. Moreover, the fact that corrosion occurs only in one particular area is a bit confusing. The manufacturer says it’s electrochemical corrosion, but even after taking appropriate measures, the problem hasn’t been resolved
It’s hard to say; there are definitely no chloride ions in the exhaust fumes, but they are present in water. Everything is calculated, so theoretically there shouldn’t be any chloride ions. Moreover, the fact that corrosion occurs only in one particular area is a bit confusing. The manufacturer says it’s electrochemical corrosion, but even after taking appropriate measures, the problem hasn’t been resolved
If funds permit, technical upgrades to the materials can be considered to prevent electrochemical corrosion, such as by using galvanized materials.
What are the pH value of the solution and the amount of ammonium sulfide by-products?