Warning for solid-liquid non-equilibrium separation in Aspen
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I followed the steps outlined in Bao Zonghong’s book \"Chemical Engineering Calculations and Software Applications\" to simulate Example 2-10, but warnings kept appearing after several attempts. I would be very grateful if any experienced users could take a look when they have time! The attachment is a simulation file.
When you set the value to 0.99 for solid calcium hydroxide, it shouldn’t be set in the MIXED stream; setting it in the CISOLID sub-stream will do just fine. Additionally, CA(OH)2 is a strong electrolyte, and this compound does not exist as a separate component in solution, so there’s no need to define it. You also didn’t need to provide an ionization equation for it
This post was last edited by ljy3033 on 2017-2-21 at 16:58. Thanks to the moderator for the reply. As you suggested, I set the calcium hydroxide retention rate to 0.99 in the CISOLID sub-process flow; however, the operation results showed that all the water ended up in the \"5solid\" stage – that can’t be right. I also want to ask what “non-conventional solids” mean? My own understanding is a solid that is partially dissolved in a solvent, but this seems inappropriate for this question as well (calcium hydroxide is slightly soluble in water and cannot fully ionize in it).
It’s probably a version issue; mine works fine. If that doesn’t work, please go to the mixed logistics settings and enter 1 for everything, and fill in the amount to be retained. As for unconventional solids, these are presumably solids whose physical properties aren’t built-in in Aspen, such as coal, dust; sometimes polymers can also be classified as unconventional solids
CISOLID is a conventional solid, while NC is unconventional
I followed the steps in the book for simulation, and the result was that all the alkaline water was in 5SOLID. I’d like to know how you handled it in the end
I’m sorry; it was a simulation from a long time ago. I wasn’t able to identify the problem at that time, and due to other matters, this issue was left unaddressed