Hi Jeff: I have used hammer mills, ball mills, and roller mills for size reduction of both straw char and charcoal. In all cases the MC of the char needs to be low enough not to make a paste (I have made this mistake before). I used a New Holland mixer mill (hammer type), some fine dust particles escape but it is not too bad, the most dust is created when using the unloading auger to bag the char, this can be mitigated by tying a filter cloth around the auger outlet.
I have used a ball mill with ceramic balls and rubber door seals, this is pretty much dust free but I found production to be terribly low and product sizing to be very inconsistent. The very best I found is a roller mill. This is both fast and can be "housed in" to easily control dust, then follow Mark's suggestions to extract the very fine particles at the outlet. You can adjust sizing by adjusting roller spacing, or adding another set of rollers below the first. Cheap small roller mills can be found in the agri sector but must be modified for char purposes. Phil Marsh Marshbros. 250 569-7858 -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Jeff Davis Sent: August-25-11 8:56 PM To: Gasification List Subject: [Gasification] Charcoal Reduction Mill Dear List, What would be the best style of mill to reduce weed and soft wood charcoal (mostly weed). This would be for charcoal Fireball production. All advice will be appreciated. Reduction might be 2 mm to dust. Enough dust to fill in the larger 2 mm particles. Might be possible to have some particles larger than 2 mm. Production is difficult for me to pin down but lets say 400 lbs/hr (180 kg/hr). More is better but less would be OK for now. The more I think about it a lot less would work for now. Would a farm hammer mill with cyclone bagger be a formula for a dust storm? Clueless, Jeff _______________________________________________ Gasification mailing list to Send a Message to the list, use the email address [email protected] to UNSUBSCRIBE or Change your List Settings use the web page http://lists.bioenergylists.org/mailman/listinfo/gasification_lists.bioenerg ylists.org for more Gasifiers, News and Information see our web site: http://gasifiers.bioenergylists.org/ _______________________________________________ Gasification mailing list to Send a Message to the list, use the email address [email protected] to UNSUBSCRIBE or Change your List Settings use the web page http://lists.bioenergylists.org/mailman/listinfo/gasification_lists.bioenergylists.org for more Gasifiers, News and Information see our web site: http://gasifiers.bioenergylists.org/
