2 replies to this topic

[barley]

A suitable vacuum pump should be selected to give satisfied operational condition for the column,
Currenly, I am facing a problem to select the suitable vacuum pump for my project as the top column temperature is too high(160 C at 35 kPa) as most vacuum pump operated in between 30 to 50degree C. Is there any good suggestion for this condition?

[Zauberberg]

Have you considered installing a pre-condenser? For example, this is mandatory configuration in Crude Vacuum Distillation units having velocity steam inside the heater coil and stripping steam being injected in tower bottoms (so-called "wet towers"). Precondenser will add pressure drop to the system, but it will reduce vapor load on the vacuum pump (I presume we are talking about overhead vacuum pump). What is also important, why is vacuum pump mandatory for your system? Can you use steam jets instead?

However, speaking in general - installing a precondenser would be the most elegant solution. But we don't know any details about your application, and you haven't uploaded any sketch.

[Art Montemayor]

Barley:

Sometime ago, I posted an Excel Workbook titled "Producing and Maintaining a Vacuum". The is workbook is posted for instant download in the thread (which is rather long, because everyone -excep you - has downloaded it).

Use the Search feature in the Forums and locate the thread and you will have your answers. I show you how calculate the proper capacity, explain why the calculations are done that way, and then give you typical examples of how the calculations are done.

Good luck.