<div dir="ltr"><div>Hello Rajan and all;</div><div><br></div><div>In TLUDs, tars may condense in the char above the pyrolysis front, if the temperature decreases substantively with height in the char layer.</div><div><br></div>
<div>However, your assertion that ---</div><div><br></div><div>"The pyrolysis process has to be extended by a couple of minutes ( after the flame drops down ) - so that all volatiles in the charcoal are "forced out" ( with the high temperature of charcoal burning ) which<br>
increases the porosity of charcoal."</div><div><br></div><div>--- may be true, if the temperature of the char increases during the charcoal gasification phase. Evidence of this can be seen in Figure 4 of the following paper. It is for a forced-draft TLUD running at a superficial velocity of 4.5 cm/s.</div>
<div><br></div><div><p><font face="Tahoma"><font face="Tahoma">Varunkumar, S; Rajan, NKS; Mukunda, HS. 2011. Single particle and packed bed combustion in modern gasifier stoves—density effects. Combustion Science and Technology 183: 1147-1163. </font></font></p>
<p><font face="Tahoma"><a href="http://cgpl.iisc.ernet.in/site/Portals/0/Publications/ReferedJournal/Single-Particle-and-Packed-Bed-Combustion.pdf">http://cgpl.iisc.ernet.in/site/Portals/0/Publications/ReferedJournal/Single-Particle-and-Packed-Bed-Combustion.pdf</a></font></p>
<p><font face="Tahoma">(You may need to use a download assist program to get this pdf)</font></p></div><div><br></div><div>Can anybody corroborate these observations?</div><div><br></div><div>Cheers, </div><div>Julien.</div>
<div><br></div><div><br clear="all"><br>-- <br></div><div dir="ltr">Julien Winter<br>Cobourg, ON, CANADA<br></div>
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