Hi, I'm doing a design project for the agitated filter dryer, also known as pressure filter dryer. I was just wondering if any of you gentlemen can help me with that, I'm mainly looking for the chemical principle associated with this unit. Thank you!

Google for manufacturer web sites. These should have info or application case studies.

Thank you all for your kind comments. Kieran, im sorry yes i did mean the pressure nutsche filtration, Thanks alot!

A pressure filter dryer can basically be treated as a batch contact (conduction) dryer for the drying stage. Basic calculation methods can be found in Perry's Chemical Engineers Handbook, Coulson and Richardson and other standard texts - probably adequate for what you need. Likewise the filtration stage can be calculated as a standard pressure filtration.

There is typically a hot nitrogen flow thru the solids, which are agitated, during the drying phase.

Or, to put Jim's comment another way - there should be a hot nitrogen flow if the dryer was designed or specified by good process engineers. But I have seen a surprising number of filter dryers just working with cold nitrogen on blowdown and drying, and saddling the users with much longer drying times as a result.

Hot nitrogen should theoretically be better for the blowdown phase as well, as the surface tension of the liquid is reduced and it dewaters more easily to a lower moisture content, thus saving significant energy. However, I'm not sure how widely this is used. In paper drying, which is of course very energy intensive, huge savings were made by heating the first few rollers.

The Filter Dryers are not necessarily used to produce a dry or wet cake. the separated solids can be reslurried and transferred to a subsequent vessel for further processing. If the wet cake can be reslurried without final removal of solvent this is a an additional energy savings to help justify the expensive filter dryer unit.

Thank you all for the comments, really appreciate it! Well the Filter Dryer process I'm designing, is first to strip/filter out the mother liquor with all the unwanted solvents out leaving behind the product ("R-flurbiprofen" that's what i'm after), then drying it and finally as Horwath mentioned reslurring the cake with toluene. The problem i'm having is finding the right dimensions for the unit. But now i'll follow what Ian said, and see how it goes. Again thanks alot for the help everyone!!!