Bruce, and List.
FWIW, construction wood (houses) has a rough R value of 1.2 per inch (so a 2 by 4 is about R 4.2 ( 3.5 X 1.2 )). This is considered "kiln dried wood", air dried would be somewhat less, (say R 1) wet wood, way down, R 0.3. Your observed effect of the outer surface of a chuck of wood is exactly why I only use wood chips for gasification, they do NOT have this effect, they instantly go from wood to charcoal (in under 1 second), they stay intact if the char state, and do NOT introduce tars and phenols farther down, in the process. chips are IDEAL for gasifier use. Greg -----Original Message----- From: [email protected] [mailto:[email protected]]on Behalf Of Bruce Jackson Sent: Wednesday, December 22, 2010 7:58 AM To: Discussion of biomass pyrolysis and gasification Subject: [Gasification] now for something really boring... Where can I look to see the experimental results of heat transfer through wood? I took to heart what folks said about destructive distillation. What I see in the stove, is that the wood isn't absorbing the heat as fast as the heat from the burning outer surface is making it. In other words the wood is both destructively distilling, and drying. It made me wonder what would be the optimal BTU input per pound (insulated container of course) for wet wood. Also I wonder does the BTU input vary after the moisture content changes? (this from distilling ethanol, you need higher temps at the end of a batch run to push the EtOH out of the remaining water) I was thinking about the center of the blocks being so well insulated by the remaining carbon that the water couldn't see the heat right away (or as fast as the water on the outer perimeter does). Or is this a case of very gently heating the blocks until they are above 212F @ 1ATM, then cranking up the input. I betcha betcha these things are known extensively in Robert Kana's community of furniture manufacturing. thanks, BPJ "LOOK! A chicken!" _______________________________________________ The Gasification list has moved to [email protected] - please update your email contacts to reflect the change. Please visit http://info.bioenergylists.org for more news on the list move. Thank you, Gasification Administrator ----- No virus found in this message. Checked by AVG - www.avg.com Version: 10.0.1170 / Virus Database: 426/3331 - Release Date: 12/22/10 _______________________________________________ The Gasification list has moved to [email protected] - please update your email contacts to reflect the change. Please visit http://info.bioenergylists.org for more news on the list move. Thank you, Gasification Administrator
