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</o:shapelayout></xml><![endif]--></head><body bgcolor=white lang=EN-CA link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'>All things considered, I think I would prefer a retort like the ones made by Chris Adam. The reason is that the fuel does not burn will in the first place and because of the dense packing, it will be difficult to properly supply at least a little air to the centre of the bundle.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'>The retorts work by sealing the material into a metal or concrete shell and heating the metal bottom with some other fuel (anything). Once the gas production is going well, the gases are ignited in the same flame as the external fire. Then it becomes a self-heating retort. There are industrial versions of this with multiple retorts but the system works fine with a single one.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'>Because the bales will stack very tightly, it is worth making the kiln to suit the fuel size. It needs to be very air tight to prevent any burning inside. It is only heated by exothermic reactions started off and supported by heating the plate under one end (or the whole thing depending on how you construct it). The method produces very little smoke and you can in theory fire bricks or something with the excess heat.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'>Regards<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'>Crispin<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal><span style='font-size:13.5pt'>If I were trying to char bales of straw I would start with a kiln that tumbles, like an industrial dryer. </span><o:p></o:p></p></div><div><p class=MsoNormal><span style='font-size:13.5pt'>If you tumbled the bales in a cage the straw would fall out to the bottom of the kiln as it chars.</span><o:p></o:p></p></div><div><p class=MsoNormal><span style='font-size:13.5pt'>I charred a square bale (actually rectangular) of wheat straw in my barbecue cooker once. I replaced the bale strings with wire and the whole bale cooked to char and stayed together. It stunk up the place.</span><o:p></o:p></p></div><div><p class=MsoNormal><span style='font-size:13.5pt'>Lanny</span><o:p></o:p></p></div></div></body></html>