About corrosion protection of catalytic cracking absorption stabilization system
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Regarding the corrosion of the catalytic cracking stable absorption system, it is mainly HCN-H2S-H2O type corrosion environment. Please ask friends who know more.: 1. Are corrosion inhibitors used as anti-corrosion means in the corrosion protection measures for this system? 2. What type of corrosion inhibitor should be used, oil-soluble or water-soluble? 3. If corrosion inhibitors are used, especially soluble corrosion inhibitors, what impact will they have on the oil quality? Thanks!
There are three protective measures for this system:: 1. Adopt continuous water injection measures, the purpose of which is to dissolve and dilute H2S, NH3 and HCN ； 2. Add polysulfide to the injection water to reduce the HCN content ； 3. Inject corrosion inhibitor. The first one is the most important and effective protective measure. If water injection still cannot ensure that the HCN content is below 20-25ppm, the second protective measure can be considered. As for the injection of corrosion inhibitors, it is generally not recommended, mainly because: 1.Higher cost ； 2. Corrosion inhibitors can only provide good protection in the liquid phase and "wet" area of the logistics, but cannot provide protection in the vapor phase area of the equipment.
Anti-corrosion water injection in the absorption stabilization system. This is the first time I have heard that if water exists in the deethanizer tower, the reboiler may not be able to circulate. If water exists, will it accelerate hydrogen sulfide acid corrosion? Can you tell me which refinery did this? hehe. This post was last edited by guoguangyu1 on 2008-3-25 08:45 ]
I think it is impossible to be water-soluble. If water-soluble is at 100 degrees Celsius (less than 100 under high pressure), water and oil are generally immiscible, which will also have a great impact on the quality of the product!
We are using anti-corrosion water injection in the absorption stabilization system, and the effect is pretty good. Because there is a condensed oil tank, there are three separations of oil, water and gas, so there is no water in the deethanizer tower. hehe