Pete, Several compacting screw feeders have been used with gasifiers. A few are commercially available. They do work but there is a limit to the pressure you can withstand and the material must be uniform. Often the seal is not reliable and dry fuel is very abrasive.
Dry wood is about 10 lb/ft3 (160 kg/m3). A bulk density of about 16 lb/ft3 (256 kg/m3) provides very nice porosity in gasifiers and combustors for a densified product. Low density cubes or pellets break up nicely on grates and in fluidized beds. Modern wood pellets are typically 35-40 lb/ft3 (560-640 kg/m3). To get to a bulk density of 16 lb/ft3 (256 kg/m3) you need to put about 50-75 kWhe/tonne of product on the auger. Tom -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Pete & Sheri Sent: Friday, June 03, 2011 9:01 AM To: 'Discussion of biomass pyrolysis and gasification'; 'Thomas Reed' Cc: 'Hugh McLaughlin' Subject: Re: [Gasification] Sawdust in Fan TLUD Could one possibly semi-pelletize the sawdust directly at the input to the gasifier? I see pellet makers that use a screw extrusion method. If one could get enough compaction to loosely hold the particles together, right at the input point, then there wouldn't be the "spouting" discussed previously. There also wouldn't be all that pressurized air to deal with. The compacted material would also create a "seal" between the gasifier and the outside world, if needed. Pete Stanaitis -------------- _______________________________________________ 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/
