Desulfurization liquid corrosion regeneration tank
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Recently, it has been observed that corrosion in the regeneration tanks is extremely severe. The new regeneration tanks have been in use for less than two years, and the 12mm thick steel plates have corroded through; the exact cause remains unknown. Those who know the reason or have encountered this phenomenon please come and discuss it.
If the regeneration temperature is too high, the system produces a large amount of by-products. In winter, one can place a beaker containing desulfurization solution in a cold place; after one hour, the condition of the solution in the beaker can be observed.
Please explain more clearly, what kind of desulfurization liquid is it?
If it is tannin-based desulfurization solution, I believe the reasons are as follows: 1. Design issues – the original design of the regeneration tank did not include an inner lining; most alkaline desulfurization solutions require a fiberglass lining. 2. Vanadium dioxide is not added in the prescribed proportion in the tannin-based desulfurization solution, which prevents proper protection of the equipment. 3. Poor control over the components of the solution results in the formation of large amounts of by-products, accelerating corrosion of the equipment
It is necessary to analyze clearly what components are present in the desulfurization liquid and what components may be present.
Could you please give an overview of how your medication is prepared? Hello everyone, so that we can take targeted actions
Wet flue gas desulfurization is becoming less and less effective these days; there is significant pressure to meet environmental standards, corrosion is a serious issue, and most wet flue gas desulfurization methods have poor performance in removing organic sulfur
What was said upstairs is correct – the amount of waste generated during the desulfurization of tannin is very large, and environmental regulations are now stricter than ever before
In the future, wet flue gas desulfurization will gradually be replaced by advanced desulfurization methods such as NHD desulfurization, pressure swing adsorption, and low-temperature methanol washing
There is indeed a corrosion issue with tannin desulfurization. It is mainly manifested as an imbalance in the ratio of gum to vanadium. The pH value is high, with a large amount of by-products. There is a problem with the regeneration system; additionally, there is no overflow protection device, and this is caused by high levels of suspended sulfur. :handshake :lol
PDS is corrosive, while simple tannin has little corrosiveness. The vanadium pentoxide ratio should be maintained at above 1.0 g/l. It is also important to apply anti-corrosion treatment to the inner wall; epoxy resin can be used for this purpose.
There are issues with regeneration; the high amount of by-products leads to corrosion of the equipment. It is necessary to apply internal anti-corrosion treatments to the equipment. During normal operation, carbon steel coupons should be installed at the regulator to monitor the corrosiveness of the desulfurization fluid, and measures should be taken promptly in case corrosion is detected.
Although baked gel desulfurization is effective for removing inorganic sulfur, it has many drawbacks such as corrosion, tower blockage, and the inability to remove organic sulfur
What was said on the 12th floor is correct; PDS also has a certain corrosive effect. Our company uses a desulfurization solution made of a mixture of tannin and TTS, and the results are quite good
The poster had better clarify what type of desulfurization process is being used. If it’s NHD desulfurization, there are several possible reasons: 1. The desulfurization solution may have mixed with water; generally, NHD isn’t corrosive, but when water is mixed in, its corrosiveness increases. 2. The solution might be dirty, which damages the properties of NHD; therefore, better filtration is necessary. 3. There could be issues with the material used in the equipment
Let’s focus on analyzing sodium sulfate and sodium sulfite, as these are the two substances that most easily cause equipment corrosion
First, it is necessary to analyze whether the level of by-products in the system is too high, whether the Na2SO4 concentration remains above 40 g/l for extended periods, and whether the level of suspended sulfur is high. If these two parameters are high, they can cause corrosion to the equipment. Additionally, it is important to check whether the components of the system are appropriate; if vanadium pentoxide is present, the total vanadium concentration should be kept above 0.8 g/l, as this can also help prevent corrosion； Also, check whether sulfur has accumulated heavily at the bottom of the equipment over time, as this can also cause corrosion.
The tasks of the desulfurization system mean that corrosion is inevitable in this system; fundamentally, such rapid corrosion is surely due to inadequate anti-corrosion measures!
There is probably too much sodium sulfate. If you are in the north, you can let part of the desulfurization solution freeze naturally during winter, which will cause the sodium sulfate to crystallize out; doing this a few times will reduce the problem, as sodium sulfate has a relatively low solubility.
Carbon steel with a plastic PVC lining results in lower costs while also extending the service life.