Seeking help with vacuum distillation issues: The separation between Line 1 and Line 2 is not clear

Thread Content

I’m facing a problem: in a vacuum distillation unit that has been recently upgraded in a certain refinery, after it was put into operational trial use, the separation of the products from the first and second vacuum stages is not clear. I have considered the following factors: [Operational factors]: 1. Excessive heat removal from the middle section of the first vacuum stage, resulting in an excessive liquid phase flow in that stage； 2. The stripping volume in the secondary column is too low, resulting in an excessively low initial boiling point of the product from this column ； An identical set of components overlaps ； 3. Excessive bottom blowing in the atmospheric pressure column, combined with insufficient heat extraction in Column 2, results in the mixture of components from Column 2 entering Column 1 ； 【Process factors】: The excessive opening rate of the atmospheric pressure tray results in insufficient liquid phase coverage, preventing adequate contact between the vapor and liquid, or leading to excessive liquid leakage ； Another issue is flooding ； Resulting in the opposite outcome. The operational parameters have not been provided yet, so we can only prepare ourselves mentally; it’s also unclear whether the summary is accurate! I hope those familiar with the sea can offer some advice!