Low Flow Gravimetric Powder Feeder 4

[TISM]

Dear Eng-Tipers,
We are trying to find a device capable of metering fine powder (atomised aluminum-d50=15 microns) on a gravimetric basis at rates as low as 300g/h (10oz/h). Most off the shelf loss-in-weight units we have identified are unable to control at such low flows. The unit is for a process development pilot plant so innovative approaches are also welcome.
Thanks in advance.

TISM

 

[Compositepro]

These guys specialize in low flow dosing,

http://www.movacolor.com/main.php?p=dosingprinciple&l=en.

 

[unclesyd]

Have you checked with these people? We used a number of their feeders both the volumetric and loss in weight type. We feed some very tough materials with these feeders.

http://www.vibrascrew.com/index.shtml

 

[m777182]

This is a very small feed rate and I am not sure the industrial solutions will do. Much depends on how precise you want to deliver your material and where. Pressumably the powder is dry and free flowing.
Because of the particle size I would chose a system where your (conical)container stands on a weight measuring device, has a small tube inserted to the bottom and the other led onto a small injector(eductor), driven by air or a liquid. You can control the suction rate by the flow rate through the injector (via a pump, pressure controller etc). It is possible to establish a control loop.
A vibratory device will probably densify your material so that the flow will be blocked after some time and you could not aerate it to make it free flowing.
If you can afford some admixtures, bind it to pellets and use a vibrator or make a suspension and feed it as liquid.
m777182

 

[TISM]

Thanks you very much I now have 3 options I did not have yesterday, including a non-commercial one if there is nothing off the shelf.
I am however still open to suggestions just in case these pathways prove unsuitable for this system.



TISM

 

[itdepends]

Quick question.

Isn't aluminium powder at that size prone to spontaneous oxidation (i.e. combustion).

Could make life interesting.

 

[TISM]

Thanks itdepends, yes in this finely divided form the Al powder is pyrophoric hence it needs to be kept under inert gas from its formation until we can meter it into our system.

TISM

 

[JimCasey]

Another company that makes very accurate dry-powder feeders is Acrison.

http://www.acrison.com

 

[rmw]

While their specialty is gravimetric coal metering for coal fired boiler burner applications, they do make metering equipment for other bulk materials.

http://www.stockequipment.com

rmw