4 replies to this topic

[Theo Lee]

Hi im new here and currently doing my design project of acetone-isopropanol distillation column. Can i know is there any formula to calculate foaming tendency or is it something we assumed based on literature ? 

[Bobby Strain]

Your system is certainly not one that foams. Acetone and isopropanol are similar and this is one of the indicators for non-foaming, which is related to interfacial surface tension. Most of us rely on experience to determine foaming tendency. Or we consult potential tray/packing vendors. Or our friends and colleagues.

 

Bobby

[Theo Lee]

for record purpose and to benefit those infuture. the answer to foaming tendency here, http://seperationtec...calculations/. 

[Bobby Strain]

That link doesn't quite work. But it gets close enough. But this is only a small part of what you need to learn for professional practice.

 

Bobby

[Art Montemayor]

I admire and have always encouraged experienced, professional engineers to write a lot of articles regarding their know-how, experience, and knowledge in their past engineering projects.  However, there are some persons out there in the internet claiming they have the expertise and writing material on chemical engineering that is, at times, ridiculous or totally erroneous and misleading.

 

The example I cite is the website recommended by Theo Lee.  First of all, there is no subject matter at this site on foaming.  As Bobby has noted, the hyperlink yields an “error”.

 

Additionally, I don’t know who these author(s) are that write up the material at this website, but they have a big, big problem in communicating accurately, correctly, and in an intelligent engineering manner.  The material seems to be written in British English - which is OK, except that it simply does not make any sense.  Whoever is writing this stuff has been trained in British English, but doesn’t know the grammatical rules - nor are the correct engineering terms employed in the correct spots and in the correct manner.  An example of this trashy writing is taken from the site’s explanation of the Reflux Ratio, something that should be well understood by all chemical engineers:

 

"1. REFLUX RATIO
The reflux to a structure top is used to management the top heat range thereby manages the cleanliness of the expense item.
(What is a “structure top”?  Reflux is not meant to “management” the top “heat range”.  It is used to set the overhead purity.  It does no “cleaning” and I can’t figure out what the devil an expense item is!)
The quantity of reflux compared to the item is known as the ‘Reflux Ratio’.
(What is the “item” mentioned?)

The expense fluid from a distillation column is separated into 4 m3 hourly reflux and 2 m3 hourly item.”
(What is an “expense fluid? )
 

My notes and questions are in RED.

This website needs to be thoroughly cleaned up grammatically if it is to be useful to young students and engineers.  There are a lot of internet sites that deal with the topic of foaming occurring in distillation, stripping and absorber columns.  It's a matter of looking through the Web.