I am going to do the revalidation of nitrogen fertilizer plant. But I do not have experience in sizing PSV for equipment with chemical reaction. Can you give me a hint ?
Jim....safe reactive relief designs generally require specialized knowledge and experience. In a nitrogen fertilizer plant there are lots of potentially dangerous reactions. I strongly advise you to pursue assignment of these reactive relief tasks to specialists. The plant personnel are probably already well aware of these potential reactions, and I think they'll be supportive of paying for that expertise.
If the Site is equipped with a lab (research facility) you can have an arc test done on the potential reactions. I am sure you can also get these done from out side resources. Based on the results you will be able to predict if the reactions are run away reactions or not and you can scale up to design your relief system. However, more complicated reaction systems should be done by specialists.