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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Dan,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Since plants can’t read we have to watch and listen to them to find out what works. Unfortunately we’re often better at talking (prescribing) than listening. Thanks for your observations. <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Tom <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> Stoves [mailto:stoves-bounces@lists.bioenergylists.org] <b>On Behalf Of </b>Carefreeland@aol.com<br><b>Sent:</b> Sunday, June 16, 2013 5:35 PM<br><b>To:</b> stoves@lists.bioenergylists.org<br><b>Subject:</b> Re: [Stoves] Low temperature vs high temperature charcoal?<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'>Tom, Tom, Listers, <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'> I would think that there would be a reduction in tars in the higher temp chars. This might have some advantages in less surface tension of water. The tars, on the other hand may have some beneficial use in reducing, insects, fungus or bacteria growth in chars used for soil enhancement. The chars created in a gasifier or less efficient system such as an open fire or various older systems of char making would all contain more ash. The extra ash would have benefits as a nearly balanced fertilizer in the soil. Minus only nitrogen. <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'> It surprises me that higher temp chars would have a lower surface area. Has anybody studied the relationship between the time it takes to cook the char and the amount of surface area created? I would think the higher temperatures and faster cooking would rupture the cell membranes violently and to a greater extent from flashing steam. Would this create more or less surface area? Would carbonized cells have a greater CEC with tiny holes in them from slow cooking or larger more accessible ruptures from fast cooking? Would some cells not rupture completely? or be blocked in large chunks of charcoal from acting to absorb water and minerals? <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'> Obviously, the type of biomass would also be a great variable in the surface area equation as cells rupture based on their design. Old gunpowder makers knew this from experience that is why low ash, high surface area Willow and Dogwood were favored. The Dogwood for dense, high octane powder and the Willow for light, fast burninig powder. <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'> I think that nature already has figured this out in a beautiful way- as usual. Char for soil is best created in hot but inefficient forest fires. Char for use as a fuel for man is best created with a high yield and lots of hydrocarbons in a closed retort system. All other uses fall on a scale in between. The Biblical saying "Render unto God what is God's" comes to mind. And you thought it was just about taxes! <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'> I like to burn my brush in a big cut open tank in the garden. All the ash flies out into the air and lands well distributed all over the garden. This saves me the task of spreading the ash. In forest fires the majority of the char forms underground or under ash. Again, Nature is still one or many steps ahead of us. <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'> Only questions, no answers as usual. No lab or even a greenhouse anymore to experiment with. Have fun all you college types. Let me know what you find. I do still read some of the letters now and then.<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'> Keep Charring and Stoving, <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'> <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'> Dan Dimiduk <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'> From the peanut gallery. <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'> <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'>In a message dated 6/16/2013 4:41:37 PM Eastern Daylight Time, <a href="mailto:tmiles@trmiles.com">tmiles@trmiles.com</a> writes:<o:p></o:p></span></p></div><blockquote style='border:none;border-left:solid blue 1.5pt;padding:0in 0in 0in 4.0pt;margin-left:3.75pt;margin-top:5.0pt;margin-bottom:5.0pt'><p class=MsoNormal style='margin-bottom:12.0pt'><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'>Stephen Joseph should comment on the target "optimum" range set out by<br>Lehmann and others of 450-550 C which seems to have guided most research.<br>According to their work an increase in temperature to 500-700C would appear<br>to result in slightly lower yield and surface area. pH and CEC would be<br>about the same. Trials with different plants and soils since this early work<br>may tell us a different story. <br><br>We have had good results with limited use of higher temperature pyrolysis<br>and gasifier chars, in the 500-700C range or even higher, when used in<br>erosion control, filtration, vermiculture and soil-less media. The main<br>drawback of a gasifier char is a lower char yield. <br><br>Tom Miles<o:p></o:p></span></p></blockquote></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'> <o:p></o:p></span></p></div></div></body></html>