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Solvent loss in a reactor system when vacuum applied? Is there any method to calculate that.
- Thread starter atulguhe1
- Start date
A dynamic material and energy balance at equilibrium conditions should calculate that. A dynamic simulator would ease the burden of all these calculations, but that does not make it easy. You may get some benefit with a steady-state analysis at two conditions (atmospheric and under vacuum) and looking at differences.
Good luck,
Latexman
To a ChE, the glass is always full - 1/2 air and 1/2 water.
Good luck,
Latexman
To a ChE, the glass is always full - 1/2 air and 1/2 water.
- Thread starter
- #3
I think what latexman is trying to say is that its difficult.
I could suggest the following methodology:
The vacuum pump will lower the pressure to the boiling pressure of the solvent at the liquid mix. Then it will evacuate solvent. As the solvent boils assuming no heat input the liquid will get colder and colder and the boiling pressure will the drop. This will continue until the liquid is so cold that the boiling pressure equals the lowest vacuum that your pump can create. Assuming no heat input no more solvent will boil off. If you have an heat input adjust accordingly. Remember to check if there is enough solvent for this process. Also, if there are several component to the liquid mix you may have to do flash calculation to calculate the composition of the vapour being boiled off and do a mass balance accordingly. This can be done as an "end point calculation" where you dont consider time if you disregard heat input. If there is heat input then you must do it by time steps and the you will have to consider the capacity of your vacuum pump.
Best regards, Morten
I could suggest the following methodology:
The vacuum pump will lower the pressure to the boiling pressure of the solvent at the liquid mix. Then it will evacuate solvent. As the solvent boils assuming no heat input the liquid will get colder and colder and the boiling pressure will the drop. This will continue until the liquid is so cold that the boiling pressure equals the lowest vacuum that your pump can create. Assuming no heat input no more solvent will boil off. If you have an heat input adjust accordingly. Remember to check if there is enough solvent for this process. Also, if there are several component to the liquid mix you may have to do flash calculation to calculate the composition of the vapour being boiled off and do a mass balance accordingly. This can be done as an "end point calculation" where you dont consider time if you disregard heat input. If there is heat input then you must do it by time steps and the you will have to consider the capacity of your vacuum pump.
Best regards, Morten
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