<html><head></head><body dir="auto" data-blackberry-caret-color="#00a8df" style="background-color: rgb(255, 255, 255); line-height: initial;"><div style="width: 100%; font-size: initial; font-family: Calibri, 'Slate Pro', sans-serif; color: rgb(31, 73, 125); text-align: initial; background-color: rgb(255, 255, 255);"><br name="BB10" caretmarkerset="INVALID" class="markedForCaretMarkerRemoval"></div> <div style="width: 100%; font-size: initial; font-family: Calibri, 'Slate Pro', sans-serif; color: rgb(31, 73, 125); text-align: initial; background-color: rgb(255, 255, 255);"><br>Dear Jock</div><div style="width: 100%; font-size: initial; font-family: Calibri, 'Slate Pro', sans-serif; color: rgb(31, 73, 125); text-align: initial; background-color: rgb(255, 255, 255);"><br></div><div style="width: 100%; font-size: initial; font-family: Calibri, 'Slate Pro', sans-serif; color: rgb(31, 73, 125); text-align: initial; background-color: rgb(255, 255, 255);">What is the formula used to say the charcoal yield is 20%?</div><div style="width: 100%; font-size: initial; font-family: Calibri, 'Slate Pro', sans-serif; color: rgb(31, 73, 125); text-align: initial; background-color: rgb(255, 255, 255);"><br></div><div style="width: 100%; font-size: initial; font-family: Calibri, 'Slate Pro', sans-serif; color: rgb(31, 73, 125); text-align: initial; background-color: rgb(255, 255, 255);">Thanks</div><div style="width: 100%; font-size: initial; font-family: Calibri, 'Slate Pro', sans-serif; color: rgb(31, 73, 125); text-align: initial; background-color: rgb(255, 255, 255);">Crispin </div><div style="width: 100%; font-size: initial; font-family: Calibri, 'Slate Pro', sans-serif; color: rgb(31, 73, 125); text-align: initial; background-color: rgb(255, 255, 255);"><span style="font-size: initial; text-align: initial; line-height: initial;"><br name="BB10" caretmarkerset="INVALID" class="markedForCaretMarkerRemoval"></span></div><br><div id="_originalContent" style=""><meta http-equiv="content-type" content="text/html; charset=utf-8"><div>Today I added 9 more secondary air ports just above the first 29. The results were predictable:</div><div><br>1. Less draft on the already restricted primary made starting even trickier;</div><div><br></div><div>2. The red,orange hot carbon flame issue was clearly abated, if not fully eliminated - ie fewer moments of soot clearly being ejected.</div><div><br></div><div>3. Run time was slightly extended - ie pyrolysis was a bit slower;</div><div><br></div><div>4. Peak temperatures were lower which showed up as less thermal damage to the metal parts, esp, the central column in the burner.</div><div><br></div><div>5. Biochar yield went up slightly to about 20%. Nice stuff too.</div><div><br></div><div>Sometime in May I will try a reactor with about twenty five ½ inch holes in a single layer for secondary air.</div><div><br></div><div>That's it for now.</div><div><br></div><div>Thanks,</div><div><br></div><div>Jock</div><div><br name="BB10" caretmarkerset="INVALID" class="markedForCaretMarkerRemoval"></div><!--end of _originalContent --></div></body></html>