Dear Dr Tom Thanks for popping up.
>O Pyrolytic Gasification (TLUD and larger) which primarily gasifies the cellulose and pyrolyses the lignin to ~20% charcoal Does the fact this is from lignin mean that there is something fundamentally different about the structure of the char product compared with commercial charcoal? Is it just a 'temperature thing'? >The smoke from a TLUD stove will leave a deposit on a cold steel plate. I was interested in finding out how much "tar" was in the TLUD combustible gas before it is burned. I have observed quite a lot of tar on the pots when the flames of TLUDs is not given time to burn completely. Another problem observed is that using wood (not pellets) in a TLUD with fairly high moisture content (like 15-20%) seems to produce quite a lot of fuel moisture-sourced condensation on the pots, probably because of the strong thermal connection between the two ends of the chunks of wood. So far it appears the wood dries early and completely, then pyrolyses as usual. This provides several measurement problems for both volume-based (hood) and chemically balanced test methods (sample+scale). It may be that the products I am seeing allow too much combustion, but there does not seem to be an easy way to spread the evaporation over a longer time. Ideas are welcome. To break the thermal connection means physically separating the wood into smaller pieces, a task strongly opposed by users. One conclusion I can draw is that pyrolytic combustion of wet wood (which is already a problem to burn) is perhaps more difficult to start and manage that other types of combustion. Tinkering with the air supply can produce wonders but cooks may not be willing to do that when there are much lower attention methods of burning the same fuel. In some places people are pretty attentive to using waste heat from stoves to dry the fuel for the next day but that is to get it down towards 15%, not to really dry it. Thanks Crispin _______________________________________________ Stoves 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/stoves_lists.bioenergylists.org for more Biomass Cooking Stoves, News and Information see our web site: http://stoves.bioenergylists.org/
