Which is more corrosive, sulfur dioxide or nitrogen dioxide?
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The gas contains small amounts of sulfur dioxide and nitrogen dioxide; the temperature is around 350 degrees, and water vapor is also present in the gas. Which one, sulfur dioxide or nitrogen dioxide, has greater corrosivity? Above the dew point, is this corrosion noticeable? What methods can be used for preservation? Thank you for the advice
If it is a dry gas, it hardly corrodes metal materials; however, in the presence of water, sulfur dioxide forms acids in water, thereby causing corrosion to the materials； Nitrogen dioxide converts to nitric acid in water, and both of these substances are corrosive. The degree of corrosion depends primarily on the concentration of the acid; for metal materials, the corrosion effect is quite significant.
Thank you. If it is above the dew point, will the corrosivity be significantly reduced? 350 degrees should be higher than the dew point temperature. Is that the case? I don’t know much about corrosion; I hope to get a detailed explanation.
The corrosion on the circulating water side of the refrigeration oil cooler is quite severe; in extreme cases, it can cause pipe blockages. All parameters of the circulating water are normal, and the water in the circulating water tank is clear and visible to the bottom. What could be the cause of this? For the circulating water, the relevant parameters are as follows: pH 8.81, Cl- 3.44 mg/l, conductivity 0.73 μs/cm, Mg2+ 1.15 mg/l; Ca2+ was not detected. The temperature of the refrigeration oil is below 50 degrees. Please advise
At a gas temperature of 350 degrees, there is no need for concern regarding corrosion; no corrosion occurs at this temperature. It is well above the dew points of water and these two acids, so condensation that could lead to corrosion does not take place.
The solubility of the gas at that temperature and the leakage temperature should be taken into consideration. A higher solubility and a higher leakage temperature certainly indicate greater corrosivity. Last edited by nanjingdaxue on 2009-4-14 19:42.]