Strange question! !
Thread Content
The components of methyl acetal were specified; the database indicates that its boiling point is 124 degrees, while Baidu shows that it has a boiling point of 45.5 degrees. Considering the process conditions, the boiling point of methyl acetal should indeed be 45.5 degrees. It’s strange, however, why there is such a large difference ? I want to replace 124 degrees with 45.5 degrees; how should I make the change? I checked the help, but only found the option for user customization; however, I don’t need to customize any components either – I just need to modify one of the parameters. How can I do that? This post was last edited by aquariusbaby on 2009-4-7 14:41]
Hello! Only by understanding the problem comprehensively and in detail can everyone step forward to help you overcome the difficulties. If confidentiality is not an issue, you need to specify your own simulation conditions and tasks, as well as the difficulties you are facing; if necessary, please attach your BKP file. In this way, experts can quickly identify where the problem lies. Wish us mutual progress!
What I simulated was the overhead condensation process in a methyl acetal distillation column. The top temperature is 40 degrees, with a methanol mass fraction of 11% and an acetals mass fraction of 89%. When defining the components, by checking the review, I found that the TB value for methylal (C3H8O2) is 124 degrees; as a result, the simulated exit temperature of the heat exchanger is 117 degrees, while the inlet temperature is 40 degrees, which is completely incorrect. According to Baidu Baike, the boiling point of methylal is 45.5 degrees, and this should be the value to use based on the process conditions. Now I would like to change the boiling point of methylal in the database to 45.5 degrees and run the simulation again. By entering the molecular formula of methylal in the user-defined settings, I was able to modify its boiling point. When returning to the review section, the original data in the TB column was no longer there. Upon conducting another simulation, the outlet temperature of the heat exchanger was still 117, which indicates that the custom-modified boiling point values were not used. How can I apply my custom boiling point values in the simulations? ? ?
Just search in a few more databases – you’ll find it eventually:lol :lol
At that time, it was because the component you selected was not a methyl acetal; the name of that component is METHYLAL； rather than: 2-METHOXYETHANOL ； Good luck~~
Well, there shouldn’t be any obvious errors; I’ve worked with this system before and it works fine :)
Is it because the pressure of the medium is very high?