Deagglomeration Of Ceramic Powders
Hi Stardust,
We are focusing on ultra fine/nano grinding & classification,
so naturally we cope with serious agglomeration problems.
If you send a 500 gram dry matter sample in a suspension state, we could modify it with our "home made" surfactant.
Then we believe you could dry it in a vacuum cabinet, without agglomeration.
When the result will be to your satisfaction, we could talk business
Ezry Akkerman
Oy Cyclotec Ltd
cyclotec@gmail.com ■
Re: Deagglomeration
I need to probably let it be known that our choices of surfactant are limited because of toxicity concerns. ■
Stardust,
Consider the use of [solid] powder dispersing agents such as fine or fumed silicas or [solid] powdered stearates. These work fantastic at low level additions. You can measure the flowability properties of your powder (as an analog) to characterize the degree of deagglomeration. ■
Re: Deagglomeration
Thank you Kevin for those excellent ideas. I will give them a try.
I'm still interested in any equipment that could help me out. ■
Stardust
You may want to consider using high velocity airflow through an Air Classifier or Cyclone Collector to break up and dry out the clumps. I realize you said "dried ceramic powder", but at that fine of particle size, it does not take much moisture at all to cause clumping. We can run samples at our lab to prove or disprove this effect. We can also utilize our air-swept classifier mill (to just disperse) and/or just dry, hot air through the Air Classifier to accomplish it. Our lab is located in Toronto, Canada. We would do this at no charge. You can visit our website at www.cms-can.com. ■
Stardust
We can also separate fine fractions from coarse fractions using the Air Classifier and/or Cyclone; considered it functioning as a dynamic screener. Feel free to call me to discuss your ideas. ■
Re: Deagglomeration
I once took a look at different mills to de-agglomerate a 1-5micron powder that was in the form of friable marbles. The best quality product was produced by a jet mill, which could be good for low thru put like yours. I had good results with a large air swept horizontal shaft hammer mill, the key was to keep the mill packed full so the chunks rubbed together. If you have the classifier open loop than you can dry the stuff at the same time. With the hammer mill it was closed loop with a chiller before the mill and the material moisture went from 17% to 6%. ■
Deagglomeration
Hello everyone,
I would like to deagglomerate dried ceramic powders back to their wet milled size of 3-5 micron.
Basically I need to turn dirt clods into fluffy powder.
To be perfectly honest, I'm small scale compared to a lot of you guys. We probably do around 300-500kg a month. Right now, however, we're doing this by hand-rubbing through a 63 micron sieve.
Is there something that can help me do this better? The vibratory sieves we got don't cut it because our material is hygroscopic which makes it need to be forced through.
I've been exploring all sorts of surfactants and dispersants for their ability to soften these agglomerates post drying. I don't even have a way of objectively measuring how hard these agglomerates are. Is there a machine that can help me determine how hard an agglomerate is?
Any and all help is appreciated. I apologize in advance for not being as "bulk" as the rest of you; if there is someplace I'd be better off seeking help please let me know. ■