Air velocity for powder transfer through pipes

[bif]

I am after some rule of thumb design info looking at recommended air velocity requirements for transporting powder through pipes,

The application is for a a system where material is fed off a vibrator in air, rather than coming in a compacted form

I have a recollection of using 15 - 25 m/s as a velocity and an airowder mass ratio of between 20:1 and 10:1 respectively a few years ago on another job, but can't find any of my old references, just to check I am in the right ball park.

Thanks

 

[quark]

http://www.cheresources.com/pnuconvey.shtml

 

[dcasto]

the Frounde Number > 1.0.

 

[nbog]

Gas velocity should be above "saltation velocity" but going to high will cause erosion (abrasion) in your pipeline (mostly bends). Try to find recommended velocities for your material, but be careful - recommended values are safe as long as your powder's morphology (particle shape) and size distribution are close to the morphology and PSD of the material that the recommendation is based on.
Another link

http://www.erpt.org/014Q/rhoe-03.htm

Nick

 

[MJCronin]

blf..

Search for information, white papers etc. under the topic of "pneumatic conveying".

There seem to be no rules of thumb in this field..

The cheapest decision may be to have a sample tested...

Try "dynamic air"

http://www.dynamicair.com

Let us know what you decide..

-MJC