[Gasification] Screw feed TLUD stove

[Thomas Reed]

Crispin and all.

I Don't agree that most TLUDS completely burn wood in stage one.  In a well packed bed the rising air first burns the easy VOLATILES from the cellulose, leaving charcoal,  then moves on to the next layer of wood before any air can reach the charcoal.

However, in a more open pile, such as a brush pile, air can bypass the burning VOLATILES and also burn the charcoal.

It requires very little air to release the volatiles by pyrolysis, but a great deal more to burn charcoal.

More later...

Tom Reed


Dr Thomas B Reed
President, The Biomass Energy Foundation
www.Woodgas.com

On Jul 27, 2011, at 3:23 PM, "Crispin Pemberton-Pigott" <crispinpigott at gmail.com> wrote:

> Dear Tom
> 
> Would you agree that some TLUD's bur wood and some burn volatiles? I recall
> you explaining that the superficial air velocity determined which it would
> be. The BP stove in India burns the whole fuel but does so in two distinct
> stages.
> 
> I have seen a pellet burner that was not a bottom-fed but a side-fed one.
> The fire burned everything ash from left to right and the ash fell off the
> far side. It looks like the Austrian bottom feeders are burning all the fuel
> to ash and even have an ash compactor on output outside the larger units.
> 
> Looks like both systems are in widespread use.
> 
> Best regards
> Crispin
> 
> 
> -----Original Message-----
> From: Thomas Reed [mailto:tombreed2010 at gmail.com] 
> Sent: 26 July 2011 18:43
> To: Crispin Pemberton-Pigott; STOVES
> Subject: Screw feed TLUD stove
> 
> Dear Crispin 
> 
> The TLUD stove doe not actually burn wood;  it burns the volatile component
> of the wood, the cellulose and hemicellulose, and converts the lignin to
> charcoal having 80% of the volume of the original feed.  
> 
> So to have a continual burning stove you would need two augers, one at the
> bottom to feed in new fuel, and one halfway up, to remove the new charcoal
> and quench it.  
> 
> The idea works particularly well for wood pellets, which are much more
> amenable to feeding...
> 
> With that added, great idea, particularly for larger cooking jobs.
> 
> Tom Reed
> 
>