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</o:shapelayout></xml><![endif]--></head><body bgcolor=white 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'>Lloyd,<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'>I just subscribed you to the gasification list so you should get a welcome message. I have sponsored and hosted the gasification list since about 1996. There are about 1200 members. <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'>We maintain a website to support the list at:<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><a href="http://www.gasifiers.bioenergylists.org/">http://www.gasifiers.bioenergylists.org/</a><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'>Regards,<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><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>T R Miles Technical Consultants, Inc.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>tmiles@trmiles.com<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>www.trmiles.com<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'><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'><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'><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";color:windowtext'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext'> stoves-bounces@lists.bioenergylists.org [mailto:stoves-bounces@lists.bioenergylists.org] <b>On Behalf Of </b>Lloyd Helferty<br><b>Sent:</b> Wednesday, January 25, 2012 12:03 PM<br><b>To:</b> Discussion of biomass cooking stoves<br><b>Subject:</b> Re: [Stoves] Stoves Digest, Vol 17, Issue 35<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal style='margin-bottom:12.0pt'>Tom,<br><br> I see a *new* list for the first time: <b><a href="mailto:gasification@lists.bioenergylists.org">gasification@lists.bioenergylists.org</a></b><br>How do I join this list?<br> (Do I send <a href="mailto:gasification-request@lists.bioenergylists.org">"gasification-request@lists.bioenergylists.org "</a> ??)<br><br>Regards,<o:p></o:p></p><pre> Lloyd Helferty, Engineering Technologist<o:p></o:p></pre><pre> Principal, Biochar Consulting (Canada)<o:p></o:p></pre><pre> <a href="http://www.biochar-consulting.ca">www.biochar-consulting.ca</a><o:p></o:p></pre><pre> 48 Suncrest Blvd, Thornhill, ON, Canada<o:p></o:p></pre><pre> 905-707-8754<o:p></o:p></pre><pre> **NEW CELL: 647-886-8754 NEW**<o:p></o:p></pre><pre> Skype: lloyd.helferty<o:p></o:p></pre><pre> Steering Committee coordinator<o:p></o:p></pre><pre> NEW Canadian Biochar Initiative (New CBI)<o:p></o:p></pre><pre> President, Co-founder & CBI Liaison, Biochar-Ontario<o:p></o:p></pre><pre> Advisory Committee Member, IBI<o:p></o:p></pre><pre> <a href="http://www.linkedin.com/groups?gid=1404717">http://www.linkedin.com/groups?gid=1404717</a><o:p></o:p></pre><pre> <a href="http://www.facebook.com/group.php?gid=42237506675">http://www.facebook.com/group.php?gid=42237506675</a><o:p></o:p></pre><pre> <a href="http://groups.google.com/group/biochar-ontario">http://groups.google.com/group/biochar-ontario</a><o:p></o:p></pre><pre> <a href="http://www.meetup.com/biocharontario/">http://www.meetup.com/biocharontario/</a><o:p></o:p></pre><pre> <a href="http://grassrootsintelligence.blogspot.com">http://grassrootsintelligence.blogspot.com</a><o:p></o:p></pre><pre> <a href="http://www.biochar.ca">www.biochar.ca</a><o:p></o:p></pre><pre><o:p> </o:p></pre><pre>Biochar Offsets Group: <a href="http://www.linkedin.com/groups?home=&gid=2446475">http://www.linkedin.com/groups?home=&gid=2446475</a><o:p></o:p></pre><pre>A nation that destroys its soil, destroys itself.<o:p></o:p></pre><pre> - Franklin D. Roosevelt<o:p></o:p></pre><p class=MsoNormal><br>On 2012-01-25 12:20 PM, Tom Miles wrote: <o:p></o:p></p><pre>Philip,<o:p></o:p></pre><pre><o:p> </o:p></pre><pre>Thanks for the reference. It looks like the CarboConsult gasifier from South<o:p></o:p></pre><pre><span lang=ES-MX>Africa. <o:p></o:p></span></pre><pre><a href="http://www.carboconsult.com/"><span lang=ES-MX>http://www.carboconsult.com/</span></a> <span lang=ES-MX><o:p></o:p></span></pre><pre><span lang=ES-MX><o:p> </o:p></span></pre><pre><span lang=ES-MX><o:p> </o:p></span></pre><pre><a href="http://www.erc.uct.ac.za/jesa/jesa-currentabstracts.htm"><span lang=ES-MX>http://www.erc.uct.ac.za/jesa/jesa-currentabstracts.htm</span></a> <span lang=ES-MX><o:p></o:p></span></pre><pre>Volume 22 No 4: December 2011<o:p></o:p></pre><pre><o:p> </o:p></pre><pre>The technical pre-feasibility to use briquettes made from wood and<o:p></o:p></pre><pre>agricultural waste for gasification in a downdraft gasifier for electricity<o:p></o:p></pre><pre>generation<o:p></o:p></pre><pre><o:p> </o:p></pre><pre>Pholoso Malatji, Ntshengedzeni Sampson Mamphweli and Martina Meincken<o:p></o:p></pre><pre><o:p> </o:p></pre><pre>Biomass can be converted to energy through various thermochemical and<o:p></o:p></pre><pre>biological processes. Gasification is one of the thermochemical processes<o:p></o:p></pre><pre>that has recently gained popularity, because it achieves higher conversion<o:p></o:p></pre><pre>efficiencies than, for example, incinerators, boilers or furnaces. Fixed-bed<o:p></o:p></pre><pre>downdraft gasifiers are preferred for electricity generation, because they<o:p></o:p></pre><pre>produce very little tar, but on the other hand, they are limited with regard<o:p></o:p></pre><pre>to biomass properties, such as particle size, bulk density and moisture<o:p></o:p></pre><pre>content. Biomass material with a heterogeneous size is usually processed<o:p></o:p></pre><pre>into pellets or briquettes, which have to be mechanically strong enough to<o:p></o:p></pre><pre>be handled. Cohesive strength is provided by residual moisture and lignin<o:p></o:p></pre><pre>present in most biomass. However, the briquetting process becomes more<o:p></o:p></pre><pre>complicated if one wants to add agricultural waste products that do not<o:p></o:p></pre><pre>necessarily contain lignin as binders. The aim of this work was to process<o:p></o:p></pre><pre>wood chips, grape skins and chicken litter into briquettes that are<o:p></o:p></pre><pre>mechanically stable and have a sufficiently high energy content, as well as<o:p></o:p></pre><pre>adequate bulk density for gasification. The performance of these briquettes<o:p></o:p></pre><pre>in a downdraft gasifier was simulated with a program developed for wood,<o:p></o:p></pre><pre>which was modified to optimise the briquette yield. The results showed a<o:p></o:p></pre><pre>gasification performance comparable to solid pine wood, implying that the<o:p></o:p></pre><pre>blended briquettes could be used as fuel for a downdraft biomass gasifier.<o:p></o:p></pre><pre>Unfortunately, the briquettes proved too instable to experimentally verify<o:p></o:p></pre><pre>the performance in a gasifier. This paper describes the properties of the<o:p></o:p></pre><pre>briquettes as well as the gasification simulation results. <o:p></o:p></pre><pre><o:p> </o:p></pre><pre><o:p> </o:p></pre><pre>Tom<o:p></o:p></pre><pre><o:p> </o:p></pre><pre>-----Original Message-----<o:p></o:p></pre><pre>From: <a href="mailto:stoves-bounces@lists.bioenergylists.org">stoves-bounces@lists.bioenergylists.org</a><o:p></o:p></pre><pre>[<a href="mailto:stoves-bounces@lists.bioenergylists.org">mailto:stoves-bounces@lists.bioenergylists.org</a>] On Behalf Of Philip Lloyd<o:p></o:p></pre><pre>Sent: Tuesday, January 24, 2012 11:48 PM<o:p></o:p></pre><pre>To: <a href="mailto:stoves@lists.bioenergylists.org">stoves@lists.bioenergylists.org</a><o:p></o:p></pre><pre>Subject: Re: [Stoves] Stoves Digest, Vol 17, Issue 35<o:p></o:p></pre><pre><o:p> </o:p></pre><pre>The latest edition of Journal of Energy in Southern Africa, Vol 22 No4<o:p></o:p></pre><pre>(November 2011) has an article on the use of biowaste briquettes in a<o:p></o:p></pre><pre>downdraft gasifier for electricity production (pp 2-7)<o:p></o:p></pre><pre><o:p> </o:p></pre><pre>Prof Philip Lloyd<o:p></o:p></pre><pre>Energy Institute<o:p></o:p></pre><pre>Cape Peninsula University of Technology<o:p></o:p></pre><pre>PO Box 652, Cape Town 8000<o:p></o:p></pre><pre>Tel: +27 21 460 4216<o:p></o:p></pre><pre>Fax: +27 21 460 3828<o:p></o:p></pre><pre>Cell: 083 441 5247<o:p></o:p></pre><pre><o:p> </o:p></pre><pre><o:p> </o:p></pre><pre><o:p> </o:p></pre><pre>-----Original Message-----<o:p></o:p></pre><pre>From: <a href="mailto:stoves-bounces@lists.bioenergylists.org">stoves-bounces@lists.bioenergylists.org</a><o:p></o:p></pre><pre>[<a href="mailto:stoves-bounces@lists.bioenergylists.org">mailto:stoves-bounces@lists.bioenergylists.org</a>] On Behalf Of<o:p></o:p></pre><pre><a href="mailto:stoves-request@lists.bioenergylists.org">stoves-request@lists.bioenergylists.org</a><o:p></o:p></pre><pre>Sent: 24 January 2012 07:45<o:p></o:p></pre><pre>To: <a href="mailto:stoves@lists.bioenergylists.org">stoves@lists.bioenergylists.org</a><o:p></o:p></pre><pre>Subject: Stoves Digest, Vol 17, Issue 35<o:p></o:p></pre><pre><o:p> </o:p></pre><pre>Send Stoves mailing list submissions to<o:p></o:p></pre><pre> <a href="mailto:stoves@lists.bioenergylists.org">stoves@lists.bioenergylists.org</a><o:p></o:p></pre><pre><o:p> </o:p></pre><pre>To subscribe or unsubscribe via the World Wide Web, visit<o:p></o:p></pre><pre> <o:p></o:p></pre><pre><a href="http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists">http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists</a><o:p></o:p></pre><pre>.org<o:p></o:p></pre><pre><o:p> </o:p></pre><pre>or, via email, send a message with subject or body 'help' to<o:p></o:p></pre><pre> <a href="mailto:stoves-request@lists.bioenergylists.org">stoves-request@lists.bioenergylists.org</a><o:p></o:p></pre><pre><o:p> </o:p></pre><pre>You can reach the person managing the list at<o:p></o:p></pre><pre> <a href="mailto:stoves-owner@lists.bioenergylists.org">stoves-owner@lists.bioenergylists.org</a><o:p></o:p></pre><pre><o:p> </o:p></pre><pre>When replying, please edit your Subject line so it is more specific than<o:p></o:p></pre><pre>"Re: Contents of Stoves digest..."<o:p></o:p></pre><pre><o:p> </o:p></pre><pre><o:p> </o:p></pre><pre>Today's Topics:<o:p></o:p></pre><pre><o:p> </o:p></pre><pre> 1. Re: The upside of Down feed (Alex English)<o:p></o:p></pre><pre> 2. Re: The upside of Down feed (<a href="mailto:rongretlarson@comcast.net">rongretlarson@comcast.net</a>)<o:p></o:p></pre><pre> 3. Re: [Ethos] ETHOS schedule (Choppalli Venkata Krishna)<o:p></o:p></pre><pre> 4. Re: The upside of Down feed (Crispin Pemberton-Pigott)<o:p></o:p></pre><pre> 5. Re: [Ethos] ETHOS schedule (Otto Formo)<o:p></o:p></pre><pre> 6. Re: [Ethos] ETHOS schedule (Alex English)<o:p></o:p></pre><pre> 7. Re: [Ethos] ETHOS schedule (Tom Miles)<o:p></o:p></pre><pre> 8. Total Energy Wiki launched (Crispin Pemberton-Pigott)<o:p></o:p></pre><pre> 9. Re: The upside of Down feed (<a href="mailto:rongretlarson@comcast.net">rongretlarson@comcast.net</a>)<o:p></o:p></pre><pre> 10. Re: The upside of Down feed (Crispin Pemberton-Pigott)<o:p></o:p></pre><pre><o:p> </o:p></pre><pre><o:p> </o:p></pre><pre>----------------------------------------------------------------------<o:p></o:p></pre><pre><o:p> </o:p></pre><pre>Message: 1<o:p></o:p></pre><pre>Date: Mon, 23 Jan 2012 20:45:36 -0500<o:p></o:p></pre><pre>From: Alex English <a href="mailto:english@kingston.net"><english@kingston.net></a><o:p></o:p></pre><pre>To: Discussion of biomass cooking stoves<o:p></o:p></pre><pre> <a href="mailto:stoves@lists.bioenergylists.org"><stoves@lists.bioenergylists.org></a><o:p></o:p></pre><pre>Subject: Re: [Stoves] The upside of Down feed<o:p></o:p></pre><pre><o:p> </o:p></pre><pre><o:p> </o:p></pre><pre>Dear Crispin,<o:p></o:p></pre><pre><o:p> </o:p></pre><pre>On 22/01/2012 10:36 PM, Crispin Pemberton-Pigott wrote:<o:p></o:p></pre><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><pre><o:p> </o:p></pre><pre>Dear Alex<o:p></o:p></pre><pre><o:p> </o:p></pre><pre>This is interesting news. The grate looks great, and if there is a <o:p></o:p></pre><pre>pile of char that is maintained in front, we must conspire to burn it.<o:p></o:p></pre><pre><o:p> </o:p></pre></blockquote><pre>Not so fast. I rather like the idea of a naturally formed biochar venturi:)<o:p></o:p></pre><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><pre><o:p> </o:p></pre><pre>To review, it is a crossdraft fire with all the advantages inherent in<o:p></o:p></pre><pre>it: refuellable and lots of room for flames.<o:p></o:p></pre><pre><o:p> </o:p></pre><pre>If the char builds up in front of the hopper but self-limits (i.e. <o:p></o:p></pre><pre>burns away) then it has to be eaten by the passing flame and available <o:p></o:p></pre><pre>O2. That being so, I see a couple of options. One is to admit air <o:p></o:p></pre><pre>through some small holes (1.6, 2.0mm) drilled under the early part of <o:p></o:p></pre><pre>the pile (on the grate side of the pile). That will bleed air under <o:p></o:p></pre><pre>the char which is a good way to burn it. Another is to change the <o:p></o:p></pre><pre>shape of the pipe in that area to allow ash to drop. I presume at the <o:p></o:p></pre><pre>moment the ash is blown into the larger chamber of the stove.<o:p></o:p></pre><pre><o:p> </o:p></pre></blockquote><pre>I see the odd spark or glowing particle fly into the stove. This is what you<o:p></o:p></pre><pre>see in most pellet stoves which do tend to have relatively low PM emissions.<o:p></o:p></pre><pre>In part that has to do with the way the size of the particles in the pellet<o:p></o:p></pre><pre>('sawdust' is really tiny wood chips) and how they tend to hold together.<o:p></o:p></pre><pre>When the hopper does runs out of fuel the added air flow literally blows<o:p></o:p></pre><pre>whole charred pellets into the stove. A chimney draft is nothing to sneeze<o:p></o:p></pre><pre>at, so to speak.<o:p></o:p></pre><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><pre><o:p> </o:p></pre><pre>It is highly likely you have a fairly large PM10 number compared with <o:p></o:p></pre><pre>the same fuel burned in a pile in that larger chamber because of <o:p></o:p></pre><pre>lofted ash.<o:p></o:p></pre><pre><o:p> </o:p></pre><pre>I am really pleased to hear that the flow is so reliable. I have some <o:p></o:p></pre><pre>really short fat pellets here which are probably going to feed well <o:p></o:p></pre><pre>because they are nearly marbles. Probably made with one of those <o:p></o:p></pre><pre>trochoid, concentric-ring pellet formers.<o:p></o:p></pre><pre><o:p> </o:p></pre><pre>As for the fire rising into the hopper, that is not going to happen if <o:p></o:p></pre><pre>the air velocity is high enough. Conditions we have observed it is <o:p></o:p></pre><pre>when the velocity is quite low. If the heat is enough, a rising <o:p></o:p></pre><pre>current of heated air and gas circulates in the fuel immediately above <o:p></o:p></pre><pre>the burning layer and the fire works its way up. That can only happen <o:p></o:p></pre><pre>if a) there is some air (especially from above) or b) the fuel is <o:p></o:p></pre><pre>volatile enough to run an air-free charring burn in the present of <o:p></o:p></pre><pre>enough heat.<o:p></o:p></pre><pre><o:p> </o:p></pre><pre>The advantage of coal, even with a highly volatiles one like the <o:p></o:p></pre><pre>lignite from Nalaikh mine, it is still less volatile than wood. The <o:p></o:p></pre><pre>talk of torrefied pellets intrigues me for that reason. It is more <o:p></o:p></pre><pre>likely to behave like slow roasting coal. Very controllable. There are <o:p></o:p></pre><pre>small coal pellets, say 16mm diameter which might feed well too.<o:p></o:p></pre><pre><o:p> </o:p></pre><pre>Is there any reason you can think of that the hopper, feed tube and <o:p></o:p></pre><pre>burning chamber should be round?<o:p></o:p></pre><pre><o:p> </o:p></pre></blockquote><pre>No.<o:p></o:p></pre><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><pre><o:p> </o:p></pre><pre>If you pass by the house I can show you a stove body that your burner <o:p></o:p></pre><pre>will directly attach to with several novel features. It won't be shown <o:p></o:p></pre><pre>until March and sort of solves the 'rest of a stove' for you. I am <o:p></o:p></pre><pre>pretty sure you will like it. It /might/ address the PM10 issue, or <o:p></o:p></pre><pre>not, and solves the heat extraction issues for cooking and heating.<o:p></o:p></pre><pre><o:p> </o:p></pre><pre>I have some Kanthal wire here which we are recommending for grate <o:p></o:p></pre><pre>material. It will work well for you and will hardly get hot at all. If <o:p></o:p></pre><pre>some small bits of fuel drop through (being ahead of the grate) a <o:p></o:p></pre><pre>pocket can be provided underneath to let them smoulder, feeding CO and <o:p></o:p></pre><pre>C and H2 into the beginning of the fire. No problem.<o:p></o:p></pre><pre><o:p> </o:p></pre><pre>The arrangement is made similarly on the SeTAR BLDD5 with the <o:p></o:p></pre><pre>smoulderings fed into the flaming portion of the pipe. The reason I <o:p></o:p></pre><pre>mention a wire grate is it is cheap and easy to make. But like the <o:p></o:p></pre><pre>layered flats too. It should be possible to punch that in a single <o:p></o:p></pre><pre>stroke with the right tool.<o:p></o:p></pre><pre><o:p> </o:p></pre><pre>How deep is the fuel in the hopper?<o:p></o:p></pre><pre><o:p> </o:p></pre></blockquote><pre>40 cm. I have materials to go up to 100cm, and I could take it up to near<o:p></o:p></pre><pre>the ceiling with some stove pipe, though I might have to counter balance the<o:p></o:p></pre><pre>stove:)<o:p></o:p></pre><pre><o:p> </o:p></pre><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><pre>I tried a number of things with hopper shape and decided there is a <o:p></o:p></pre><pre>general rule about bridging which is the following: if the hopper <o:p></o:p></pre><pre>tapers inwards the point of burning, there is an upper limit to the <o:p></o:p></pre><pre>height of the fuel for each degree of narrowing. I tried shoulders too <o:p></o:p></pre><pre>and they are OK further up (for example, within 1 hopper width of the <o:p></o:p></pre><pre>top of the fuel pile). On all cases, if the fuel is compressed by <o:p></o:p></pre><pre>pushing down on it or by stacking lots of fuel up, bridging occurs <o:p></o:p></pre><pre>just above the beginning of the taper.<o:p></o:p></pre><pre><o:p> </o:p></pre></blockquote><pre>These pellets are highly resistant to bridging. On the other hand I have<o:p></o:p></pre><pre>seen chips defy gravity:)<o:p></o:p></pre><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><pre><o:p> </o:p></pre><pre>The solution is agitation or a non-tapering hopper bottom.<o:p></o:p></pre><pre><o:p> </o:p></pre><pre>This is bound to be affected by the surface smoothness of the fuel <o:p></o:p></pre><pre>particle. If the pellets are shiny and hard that has to be a help <o:p></o:p></pre><pre>avoid bridging, right? I am impressed that you are able to keep it <o:p></o:p></pre><pre>feeding so well with such a significant narrowing.<o:p></o:p></pre><pre><o:p> </o:p></pre></blockquote><pre>It is difficult to measure but the pellet flow is in fact air (wind)<o:p></o:p></pre><pre>assisted. However they are more bullet than sail. Small dry wood chips are<o:p></o:p></pre><pre>sails and if they make it down through the hopper, they blow right out of<o:p></o:p></pre><pre>the tube.<o:p></o:p></pre><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><pre><o:p> </o:p></pre><pre>To you think it is necessary to tilt the flame tube downwards at all? <o:p></o:p></pre><pre>If the char pushed ahead it would be burned by the continuous heat of <o:p></o:p></pre><pre>the flame. Using wood, I can report that I have seen flames reaching <o:p></o:p></pre><pre>more than 24 inches along the tube so you may get better combustion <o:p></o:p></pre><pre>efficiency by lengthening the one you have.<o:p></o:p></pre><pre><o:p> </o:p></pre></blockquote><pre>Yes, a view of the flame is useful for understanding the process but is not<o:p></o:p></pre><pre>ideal for combustion.<o:p></o:p></pre><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><pre><o:p> </o:p></pre><pre>Thanks for an interesting (tiny) burner idea. If you bring it here I <o:p></o:p></pre><pre>have some 5mm switchgrass pellets I have had difficulty burning it <o:p></o:p></pre><pre>anything yet. Maybe...<o:p></o:p></pre><pre><o:p> </o:p></pre></blockquote><pre>I suspect the ash would bung it up, but maybe...not.<o:p></o:p></pre><pre><o:p> </o:p></pre><pre>Alex<o:p></o:p></pre><p class=MsoNormal><snip><o:p></o:p></p></div></body></html>