I am preparing specification for plate heat exchanger for sulfuric acid cooling application and I want to specify the maximum velocity in the connection and within the plate.
- As a general rule, fluids velocity should be maximized whithin the pressure drop limits of your process. Increasing velocity increases heat tranfer coefficients and reduces fouling especially for fluids containing suspended solids.
- Consider using a multipass unit if the velocity is low.
-Make sure that the gaskets material is compatible with the streams involved (especially sulfuric acid).
never heard of that limitation for plate heat exchangers...
but, for shell&tube HE, TEMA recommends impingement plates for [ρ]V² > 500.
And [ρ]V² < 4000 for total bundle entrance and exit areas.
where [[ρ]]=lb/ft³, [V]= ft/s
in any case, my plant experience with plate HE is that they usually use the same diameter as the piping - i.e. no expansion or reduction.
I have been thinking about this thread for a while now.
Regarding the nozzles, liquid velocity limitation standards as pertain to any piping/nozzles, PHE or otherwise would prevail. You must have parameters for your piping and other components in the piping trains.
Regarding the plate packs, PHE's love velocity (within parameters, of course) but higher velocity means higher pressure drop, so more often than not the system and it's pressure drop limitations are the velocity limiters in a PHE.
If you can stand the pressure drop, go for the maximum velocity your PHE supplier will allow.
If your nozzle sizing is consistent with your proper piping standards (in other words, your nozzles are not inordinately oversized,) I believe their limitations will dictate the velocity limits long before you have to worry about the plates. Just my opinion. I did not do any research that you could have done, like Google, etc.