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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;mso-fareast-language:EN-US'>Dear Tom<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;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;mso-fareast-language:EN-US'>My assessment, listening to the designers, is that this is common. The entire stove and heat exchanger has to be cleaned weekly. Looking into the access doors I see they are coated with a thick fuzzy layer of black carbon and condensed tars. <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;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;mso-fareast-language:EN-US'>The main cause is the way in which they work: bottom lit updraft, refueled by adding coal on top of the fire. <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;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;mso-fareast-language:EN-US'>When using bituminous coal in that design, the result is inevitable. I am introducing two new methods of burning coal and using the worst coal available, we will be able to get a combustion efficiency above 99.5%. One is a TLUD and the result was about 99.7% in a test run with undersized fuel. In Tajikistan we peaked at 99.99% with coal from here (Kyrgyzstan). The other stove we light tomorrow. It has a cross-draft combustor. It will probably be even better.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;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;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;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;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;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Further comment:<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif'>It’s fine to show the “ultimate” example but how frequent is chimney clogging in improved stoves? I would hope that clogging is easily recognized and correctable at this time. It is probably more due to stove use (fuel mc, etc.) than design. <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Tom<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p> </o:p></span></p><p class=MsoNormal><a name="_MailEndCompose"><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p> </o:p></span></a></p><span style='mso-bookmark:_MailEndCompose'></span><p class=MsoNormal><b><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p> </o:p></span></b></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-ZA style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>No further comment? How about adding “polyaromatic” before “hydrocarbons”?<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-ZA style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>Philip<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-ZA style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-ZA><o:p> </o:p></span></p><div><p class=MsoNormal style='background:white'><span lang=EN-US style='font-family:"Slate Pro";color:black'>Dear Photo Collectors</span><span lang=EN-US style='font-family:"Calibri",sans-serif;color:#1F497D'><o:p></o:p></span></p></div><div><p class=MsoNormal style='background:white'><span lang=EN-US style='font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p></div><div><p class=MsoNormal style='background:white'><span lang=EN-US style='font-family:"Slate Pro";color:black'>Attached is the ultimate example of a chimney clogged by long chain hydrocarbons.</span><span lang=EN-US style='font-family:"Calibri",sans-serif;color:#1F497D'><o:p></o:p></span></p></div><div><p class=MsoNormal style='background:white'><span lang=EN-US style='font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p></div><div><p class=MsoNormal style='background:white'><span lang=EN-US style='font-family:"Slate Pro";color:black'>No further comment needed.</span><span lang=EN-US style='font-family:"Calibri",sans-serif;color:#1F497D'><o:p></o:p></span></p></div><div><p class=MsoNormal style='background:white'><span lang=EN-US style='font-family:"Slate Pro";color:black'>Crispin </span><span lang=EN-US style='font-family:"Calibri",sans-serif;color:#1F497D'><o:p></o:p></span></p></div><div><p class=MsoNormal style='background:white'><span lang=EN-US style='font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p></div><div><p class=MsoNormal style='background:white'><span lang=EN-US style='font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p></div><div><p class=MsoNormal style='background:white'><span lang=EN-US style='font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p></div><div><p class=MsoNormal style='background:white'><span lang=EN-US style='font-family:"Slate Pro";color:black'>Dear Kirk, Paul and all,<br><br>Kirk: thanks for circulating your hypothesis. This seems well-founded.<br>Paul: measuring long-chain hydrocarbons / tars is part of the planned project of PhD student Thomas Kirch.<br><br>The intention is to measure the tars fairly soon. The catch is that our existing micro-GC isn't suitable for this, and finding someone who is willing to put our tars in their GC-MS is proving difficult. Until we get funds to buy our own, any suggestions for other ways of characterising the tars?<br><br>Cheers,<br>Paul</span><span lang=EN-US style='font-family:"Calibri",sans-serif;color:#1F497D'><o:p></o:p></span></p></div></div></body></html>